EGU General Assembly 2024  

Terrestrial environments and their ecosystems demand healthy, sustainable, and resilient soils. Over the past couple of decades, significant efforts have been made to safeguard global soils, yet the materials and resources responsible for soil formation have been widely overlooked.  The transition from bedrock to soil – a zone often described as ‘soil parent material’ – holds an exciting yet untapped potential for helping us address some of the largest environmental challenges, including climate change and the biodiversity crisis. In this award lecture, I will present a strand of my research programme ‘Building Tomorrow’s Soils’ which seeks to establish how soil parent materials enhance the sustainability, health, and resilience of soil systems. First, with a focus on carbon sequestration, I will highlight how the bedrock–soil transition zone has the potential to be a long-term store of organic carbon. I will then present research which shows that some soil parent materials release petrogenic (i.e. rock-derived) organic carbon into soils. These understudied inputs of organic carbon to soils are currently absent from most, if not all, soil carbon models, which threatens our ability to optimize soil carbon management in the long-term. Finally, I will argue that developing a mechanistic understanding about this transition zone – this underexplored material which is neither rock nor soil in structure and function, but a blend of both – requires a similarly cross-disciplinary approach.

How to cite: Evans, D.: Digging into the Future: The transition between bedrock and soil as an underexplored frontier zone in geoscience, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11742, https://doi.org/10.5194/egusphere-egu24-11742, 2024.

This is both an exciting and a challenging time to be a soil scientist. Societal interest in soil is thriving because of its pivotal role in food security, climate change, and biodiversity. But this interest comes with serious responsibilities, within the context of a scientific climate dominated by perverse incentives for funding and publishing. In this Philippe Duchaufour lecture I would like to reflect on some of the balances we should aim for, and the boundaries we should acknowledge, as soil scientists. I will do this for field of climate-related soil research; for the role of soil ecology in the transition towards sustainable agriculture; as well as for academic publishing.

The soil takes center stage in discussions regarding climate change mitigation. However, the focus is mostly on large-scale carbon sequestration (LSCS). There almost seems to be a dichotomy within the scientific community regarding the potential and desirability of LSCS, with exceedingly optimistic assessments finding their way to policy documents, and more critical publications on the limits or usefulness of LSCS apparently ignored. I will highlight some fundamental boundaries to large scale carbon sequestration, notably the amount of carbon available through photosynthesis. As a possible way forward, I will stress the importance of focusing on improving soil functioning rather than on increasing the carbon stock size.

The need for a transition towards more sustainable forms of agriculture while maintaining high productivity is broadly acknowledged within the scientific community. Such forms of agriculture should both include a high degree of circularity as well as a larger reliance on the benefits that soil biota provide. However, these two aspects are often not studied in relation to each other.  Earthworms provide an instructive case in this respect. It is clear that they are beneficial to crop growth – the literature even suggests an overall increase of 25% in crop yield in the presence of earthworms. Yet, this number is not realistic as many primary earthworm studies do not represent realistic systems. In particular, we should not claim that earthworms can compensate for the removal of nutrients through harvest. This can only be done through replenishment of nutrients from elsewhere – preferably in a circular manner. I will discuss how earthworms and other biota could positively affect nutrient recycling in future agricultural systems that will receive new, circular forms of soil amendments.  

Finally, scientific publishing is in crisis. Scientific articles are in many ways the basic building blocks of scientific careers, and yet the publishing process is overstretched and flawed. This is mostly related to imbalances: especially between those who pay and those who earn; and between those who write and those who review. I will highlight some of these imbalances, which are to some extend geographic, and will discuss to what extent switching to an open publishing model will resolve them. I will end with some thoughts on how to improve the publishing process, including a call for more cooperation between editors across journals to keep scientific publishing viable.

How to cite: Van Groenigen, J. W.: Beasts, Balances and Boundaries in Soil Science, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12483, https://doi.org/10.5194/egusphere-egu24-12483, 2024.

Rangelands play a crucial role in providing various ecosystem services and have significant potential for carbon sequestration. However, monitoring soil organic carbon (SOC) stocks in rangelands is challenging due to the large size of ranches and the high spatial variability influenced by climate and management factors. To address these challenges, we have developed the Rangeland Carbon Tracking and Management (RCTM) system, which integrates remote sensing inputs, survey data sources, and both empirical and process-based SOC models. In this work, we will introduce the structure of RCTM v1.0, its data input requirements, data processing pipelines, and the resulting data outputs. Additionally, we will discuss the high-resolution soil moisture data layers, baseline SOC maps, and the targeted field sampling plan generated through an empirical digital soil mapping approach. The Bayesian calibration and validation scheme for obtaining grassland plant functional type (PFT)-specific parameters using flux tower network data will also be explained. After calibration, the RCTM system generated estimates of rangeland carbon fluxes across PFTs (R² between 0.6 and 0.7) and surface depth SOC stocks (R² = 0.6) with moderate accuracy at the regional scale. The visualization of modeling results associated with long-term rangeland C dynamics at different scales will be demonstrated using the Google Earth Engine platform to inform management decisions and policymaking.

How to cite: Xia, Y., Sanderman, J., Watts, J., Machmuller, M., Ewing, S., Mullen, A., Rivard, C., and Hernandez, H.: Developing a Rangeland Carbon Tracking and Monitoring System Using Remote Sensing Imagery Coupled With a Modeling Approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-180, https://doi.org/10.5194/egusphere-egu24-180, 2024.

Soil erosion is a widespread environmental challenge with far-reaching implications for agricultural productivity, water quality and ecosystem health. Addressing this complex issue requires the use of modelling tools that empower diverse stakeholders, such as researchers and decision-makers, to simulate soil erosion systems under different scenarios. For these tools to be effective, not only they need to make good predictions, but they need to be accessible and educational, so users, regardless of their technical skills and modelling expertise, can understand and even more importantly, trust the model. In traditional soil erosion modelling, the primary emphasis to build trust is by demonstrating the model’s ability to replicate past observations, and less attention is given to build trust by providing an educational and exploratory experience. We introduce a project that aims at democratizing soil erosion modelling, making it more accessible and trustworthy to researchers, educators, decision-makers, and local communities. Leveraging the versatility and accessibility of Jupyter Notebooks, we are developing iMPACT-erosion, a soil erosion modelling toolbox to support education, land management and informed decision making. A series of dedicated Notebooks not only explain and simulate the main soil erosion processes but guides users through the main steps to enhance the credibility of the model results, i.e. sensitivity analysis, model calibration, uncertainty analysis, model evaluation and scenario analysis. The integration of interactive visualization enhances this experience by facilitating exploration of both the model configuration and the soil erosion system's response under different scenarios/decisions. This model development approach is not confined to the field of soil erosion and offers the potential to facilitate knowledge transfer and collaboration between model developers and decision makers in various domains.

How to cite: Peñuela, A.: Democratizing soil erosion modelling: A Jupyter Notebook approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1907, https://doi.org/10.5194/egusphere-egu24-1907, 2024.

             Advice for phosphorus (P) fertilisation based on soil testing using extractive methods but does not consider P sorption processes. Traditional soil P sorption capacity examined from a Langmuir isotherm batch experimental design, which is time-consuming, labour intensive and expensive. Mid-infrared (MIR) spectroscopy is a rapid analysis technique that can potentially replace the extractive technique traditionally used in soil analysis. The objective of this work was to predict the isothermal parameter of P sorption maximum capacity (Smax, mg·kg^-1) from MIR spectroscopy.

              This study created spectral libraries from benchtop (Bruker) and handheld (Agilent) MIR spectrometers by scanning samples in two particle sizes, < 0.100 mm (ball-milled) and < 2 mm. The four spectral libraries created used an archive of samples with a database of sorption parameters where soils were classified into low and high sorption capacities using a threshold value of Smax = 450.03 mg·kg^-1. To assess the optimal algorithmic method with highest Smax prediction accuracy, regression models were based on the partial least squares (PLS) regression, Cubist, support vector machine (SVM) regression and random forest (RF) regression algorithms. After the first derivative Savitzky-Golay smoothing, Bruker spectroscopies with both soil particle sizes yielded ‘excellent models’, with SVM predicting Smax values with high accuracy (RPIQ_Val = 4.50 and 4.25 for the spectral libraries of the ball-milled and <2mm samples, respectively). In comparison, the Agilent handheld spectrometer produced spectra with more noise and less resolution than the Bruker benchtop spectrometer. Unlike Bruker, for Agilent MIR spectroscopy, more homogeneous samples after ball-milling resulted in a higher accurate Smax prediction. For Agilent spectroscopy of ball-milled samples, an ‘approximate quantitative model’ (RPIQ_Val = 2.74) was obtained from the raw spectra using the Cubist algorithm. However, for Agilent spectroscopy of < 2 mm samples, the best performing Cubist algorithm can only achieve a ‘fair model’ (RPIQ_Val = 2.23) with the potential to discriminate between high and low Smax values.

              The results suggest that the Bruker bench-top spectrometer can predict the Langmuir Smax value with high accuracy without the need to ball-mill samples, highlighting the availability of the MIR spectrometer as a rapid alternative method for understanding soil P sorption capacity. However, for handheld spectrometers, the Agilent instruments can only make approximate quantitative predictions of Smax for ball milled samples. For <2mm samples, Agilent can only be used to classify low and high sorption capacity soils.

How to cite: Yang, S., White, B., Regan, F., Kent, N., Hall, R., de Santana, F., and Daly, K.: Prediction of soil phosphorus sorption capacity in agricultural soils using mid-infrared spectroscopy. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3186, https://doi.org/10.5194/egusphere-egu24-3186, 2024.

This study employs the PHYGROW simulation model to assess the 40-year dynamics of arid grassland in Jordan, focusing on the Leaf Area Index (LAI) as a pivotal indicator of vegetation health. The observed results reveal a notable decline in LAI over the study period, with the highest recorded value in 2005 (2.27) and a subsequent reduction to 1.68 in 2021. Rigorous statistical analyses, including regression analysis, confirm the significance of this downward trend, prompting further investigation into potential contributing factors such as changes in climate, land use, and soil conditions.

Interannual variability analysis identifies specific years marked by noteworthy LAI fluctuations, providing insights into the dynamic responses of the arid grassland ecosystem. Comparison with concurrent climate data underscores the intricate relationship between LAI trends and environmental variables. The study emphasizes the importance of continuous monitoring and understanding the underlying drivers of vegetation dynamics in arid regions.

The observed decrease in LAI holds implications for the overall health and resilience of the ecosystem, highlighting the need for informed decision-making in sustainable land management practices. These findings contribute significantly to the broader understanding of arid land dynamics, guiding future research and collaborative efforts with experts in related fields. Such collaborations are essential for enhancing the robustness and applicability of the results, ultimately informing conservation and resource management strategies tailored to the unique challenges of arid environments.

How to cite: Alhamad, M. N. and Abdullah, S.: Simulation Modeling of Arid Grassland Dynamics in Jordan: A 40-Year Analysis of Leaf Area Index Trends, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4117, https://doi.org/10.5194/egusphere-egu24-4117, 2024.

In the Sahel region, landscape configuration is closely linked to factors such as climate, ecology, soil composition, agronomy, livestock, and biology. Over the past decades, significant changes in these factors have been observed, including shorter rainy seasons, irregular precipitation, a decrease in biomass productivity, and rapid population growth, negatively impacting local agricultural and pastoral systems. In response to this pressure, mitigation strategies have been implemented to contribute to the improvement of local food, nutritional, and economic security. Agroforestry systems, involving a combination of trees, shrubs, crops, and animals in the same plot, represent one of these strategies. Therefore, characterizing these systems in the current context of climate change is crucial for sustainable natural resource management.

In this study, three agroforestry landscapes of the Senegalese Sahel were described, spanning a bioclimatic gradient from the Louga region (Ouarkhokh) in the north to the Fatick region (Niakhar) in the center, and the Tambacounda region (Koussanar) in the south. The data utilized included satellite imagery synthesis (Sentinel-2 and Spot), landscape variables (rainfall, evapotranspiration, biomass, and vegetation), spectral indices (NDVI, NDRE, GNDVI), and field data on land use and woody cover. The methodology consisted of three main approaches: (i) landscape stratification involving Sentinel image segmentation in 2021, selection of relevant landscape variables, and mixed discriminant factor analysis to establish landscape heterogeneity; (ii) land use and land cover mapping through supervised pixel-based classification using a Random Forest (RF) machine learning classifier with 500 trees; (iii) floristic diversity analysis by assessing floristic composition and calculating diversity indices (i.e., Shannon, Pielou, and Simpson indices).

Landscape stratification identified seven classes with distinct landscape characteristics. Classes (1, 2, and 4) in the Ouarkhokh site had lower average biomass, rainfall, and actual evapotranspiration values than classes (3 and 4) in the Niakhar site. Similarly, classes (5, 6, and 7) in the Koussanar area had higher average biomass, rainfall, and actual evapotranspiration values than the first two sites. Land use mapping showed vegetation predominance in the Ouarkhokh site, significance in the Koussanar site, and low presence in the Niakhar area. Other identified units (cultivated areas, built-up areas, water, and bare land) were dominant in the Niakhar area, present in the Koussanar site, and low in the Ouarkhokh area. Likewise, vegetation dominated in classes 1, 5, 6, and 7. Class 1 was exclusively found in Ouarkhokh, while classes 5, 6, and 7 were located in the Koussanar site. The majority of cultivated surfaces were in class 3, exclusively located in the Niakhar area. Species richness was higher in the Niakhar area (60 species, 21 families) and lower in the Koussanar area (56 species, 16 families) and Ouarkhokh area (31 species, 13 families). This landscape distribution of land use, landscape classes, and identified species highlights the influence of anthropogenic, soil-related, and climatic factors specific to each site.

How to cite: sylla, D., Diouf, A. A., and Ndao, B.: Variation of woody plants diversity and land use along a bioclimatic gradient of agroforestry landscapes in Senegalese Sahel, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5133, https://doi.org/10.5194/egusphere-egu24-5133, 2024.

The landscape-scale evaluation and modeling of the impact of agricultural management and climate change on soil-derived ecosystem services requires soil information at a spatial resolution addressing individual agricultural fields. A pattern recognition approach is presented that generates a nationwide data product. It agglomerates the multivariate soil parameter space into a limited number of functional soil process units (SPUs) that facilitate operating agricultural process models. Each SPU is defined by a multivariate parameter distribution along its depth profile from 0 to 100 cm. It has a depth resolution of 1 cm and a spatial resolution of 100 m. The methodological approach is based on an unsupervised classification procedure involving remote sensing, cluster analysis, and machine learning. It accounts for differences in variable types and distributions and involves genetic algorithm optimization to identify those SPUs with the lowest internal variability and maximum inter-unit difference with regards to both, their soil characteristics and landscape setting. The high potential of the method is demonstrated for the agricultural soil landscape of Germany. It can be applied to other landscapes and ecosystem contexts.

How to cite: Ließ, M.: A pattern recognition approach to generate soil process units for ecosystem modeling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5461, https://doi.org/10.5194/egusphere-egu24-5461, 2024.

Upscaling chamber measurements of soil greenhouse gas (GHG) fluxes from point scale to landscape scale remain challenging due to the high variability in the fluxes in space and time. This study measured GHG fluxes and soil parameters at selected point locations (n = 268), thereby implementing a stratified sampling approach on a mixed-landuse landscape (∼ 5.8 km²). Based on these field-based measurements and remotely sensed data on landscape and vegetation properties, we used random forest (RF) models to predict GHG fluxes at a landscape scale (1 m resolution) in summer and autumn. The RF models, combining field-measured soil parameters and remotely sensed data, outperformed those with field-measured predictors or remotely sensed data alone. Available satellite data products from Sentinel-2 on vegetation cover and water content played a more significant role than those attributes derived from a digital elevation model, possibly due to their ability to capture both spatial and seasonal changes in the ecosystem parameters within the landscape. Similar seasonal patterns of higher soil/ecosystem respiration (SR/ER–CO₂) and nitrous oxide (N₂O) fluxes in summer and higher methane (CH₄) uptake in autumn were observed in both the measured and predicted landscape fluxes. Based on the upscaled fluxes, we also assessed the contribution of hot spots to the total landscape fluxes. The identified emission hot spots occupied a small landscape area (7 % to 16 %) but accounted for up to 42 % of the landscape GHG fluxes. Our study showed that combining remotely sensed data with chamber measurements and soil properties is a promising approach for identifying spatial patterns and hot spots of GHG fluxes across heterogeneous landscapes. Such information may be used to inform targeted mitigation strategies at the landscape scale.

How to cite: Wangari, E., Mwanake, R., Houska, T., Kraus, D., Gettel, G., Kiese, R., Breuer, L., and Butterbach-Bahl, K.: Identifying landscape hot and cold spots of soil greenhouse gas fluxes by combining field measurements and remote sensing data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5750, https://doi.org/10.5194/egusphere-egu24-5750, 2024.

The Soil Fertility (SoilFer) project, led by the Land and Water Division at FAO, seeks to enhance agricultural practices and resilience globally, starting with five countries (Guatemala, Honduras, Zambia, Kenya, and Ghana). The project collaborates with governments and relevant national partners to establish comprehensive national monitoring and mapping systems for soil management, catering to the diverse needs of agriculture stakeholders. The Soil and Water Management Laboratory at the Joint FAO/IAEA Center serves as a crucial hub for advancing research and technical expertise in soil and water management using nuclear and related techniques. Through its multifaceted approach in collaboration with the Land and Water Division, the laboratory contributes significantly to the SoilFer project, through the development and implementation of technical training programs for and expert advising on the application of Mid-Infrared Spectroscopy (MIRS), Cosmic Ray Neutron Sensor (CRNS), and Gamma Ray Spectroscopy (GRS) to soil monitoring and mapping.

The integration of MIRS, CRNS, and GRS technologies within the SoilFer project forms a robust framework for soil monitoring and mapping, as MIRS has been shown to provide detailed insights into soil composition and carbon content, CRNS offers real-time data on soil moisture dynamics, and GRS contributes to the analysis of radioactive isotopes and elemental composition. Given the integrated nature of landscape processes, the adoption of technological approaches must mirror this complexity. Interconnected ecological, hydrological, and geological processes within landscapes necessitate a holistic and integrated technological framework. This approach ensures that diverse data streams, derived from technologies such as remote sensing, geographic information systems (GIS), and advanced sensor networks, can be harmoniously synthesized. Only through such integration can a comprehensive understanding of landscape dynamics be achieved, facilitating informed decision-making and sustainable management practices across multifaceted environmental systems. The project emphasizes the seamless integration of these advanced technologies with soil monitoring and mapping systems, ensuring a comprehensive and effective approach to soil management practices, while improving national capacity and stakeholder engagement in data-based decision making. 

The key objectives of the SoilFer project encompass the development of robust national soil information systems, the implementation of decision support systems targeting soil health, and the promotion of sustainable soil management practices. By fostering collaboration and knowledge exchange, the project aspires to build technical, increase agricultural resilience and ensure food security in the participating countries.

How to cite: Vlasimsky, M., Dercon, G., Said Ahmed, H., Daraboe, S., Yigini, Y., Tong, Y., Peng, Y., Albinet, F., Heiling, M., and Resch, C.: The Joint FAO/IAEA Center and the Soil Fertility Project: Integrating Nuclear and Related Techniques for Modelling to Support Practical Decision Management Support, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5949, https://doi.org/10.5194/egusphere-egu24-5949, 2024.

Land degradation processes have experienced a significant increase in recent decades, a trend that is projected to escalate further in the absence of any intervention. The need of adopting practices to contain, mitigate and restore degraded land have been stressed also by the new European Mission 'A Soil Deal for Europe'. To guide and support restoration actions, through a common and effective framework, an efficient monitoring approach and an adaptive ecological restoration process is needed. 

The NewLife4Drylands LIFE project provides a Protocol for design, implementation, and maintenance of restoration activities based on Nature-Based Solutions (NBS) within drylands. The Protocol, developed following the principles and inputs of some international restoration standards (SER, IUCN), is based on the identification and monitoring of degradation processes exploiting remote sensing capabilities, with the aim to integrate data derivation procedures into ecological restoration and maintenance activities. The Protocol is supported by a Decision-Making web-tool guiding trough the degradation processes, NBS along with indices/indicators with the aim to reduce the knowledge effort and helps in prioritizing options. 

The Newlife4drylands experience highlighted the heterogeneity and complexity of degradation processes, as resulted from a selected set of degraded pilot sites within Mediterranean Protected Areas, together with the issue for harmonization and standardization of ecological/physical indicators, especially those derived from satellite observations, when used as proxies of land degradation. The integrated use of both available field data (for short-term monitoring) and satellite data (for medium and long-term monitoring) have been explored to identify indicators for evaluating the effectiveness of planned restoration actions. This approach is geared, towards fostering adaptive and collaborative management of the ecological restoration process. 

Therefore, the Protocol acts as support tool for decision-makers, including public administration of Protected Areas, as well as technicians and planners. The proposed approach aims to raise awareness about the needs of drylands and opportunities provided by NBS. It serves as a guide for the identification of specific/local NBS for the restoration of drylands, beginning with the identification of degradation processes.

How to cite: D'Ambrogi, S., Assennato, F., Labadessa, R., Mazzetti, P., Rastelli, V., Riitano, N., and Tarantino, C.: NewLife4Drylands Protocol for dryland restoration in Protected Areas: an innovative tool to support restoration activities., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6126, https://doi.org/10.5194/egusphere-egu24-6126, 2024.

The Eddy covariance (EC) is a well-known technique used (among others) to investigate the ecosystem exchange of greenhouse gasses (GHGs) between the biosphere and the atmosphere (Burba et al., 2007), often required in studies on soil-plant-atmosphere interactions and GHG emissions/removals from different soil systems. The long data records from EC measurements often experience data gaps due to various reasons (BaldocchiI, 2003) resulting in  many gap-filling methods being developed over the past decades. This study is introducing the new ’miniRECgap’ (Premrov, 2024) computational tool, which is using so-called ‘classic’, traditional robust and validated modelling approaches for gap-filling the missing EC CO₂ flux measurements,  based on the application of environmental temperature and light response functions (Lloyd and Taylor, 1994; Rabinowitch, 1951) in combination with empirical/semi-empirical parameter-optimisation. ‘miniRECgap’ is a very small R package that operates in a user-friendly way via GUI (Graphical User Interface) supported scripts. It is purposely designed to be simple, operating in only 5 steps. The application of ‘miniRECgap’ will be demonstrated using EC CO₂ flux data from an Irish peatland site Clara Bog. Due to its simplicity, it is thought that the new tool may be beneficial for new R users and that it may allow for easier and less time-consuming testing of the potential suitability of ‘classic’ empirical/semi-empirical gap-filling on different datasets.

Acknowledgements

The authors are grateful to the Irish Environmental Protection Agency (EPA) for funding the CO2PEAT project (2022-CE-1100) under the EPA Research Programme 2021-2030.

References

BaldocchiI, D.D. (2003) Assessing the eddy covariance technique for evaluating carbon dioxide exchange rates of ecosystems: past, present and future.  9, 479-492.

Burba, G., Anderson, D., Amen, J., (2007) Eddy Covariance Method: Overview of General Guidelines and Conventional Workflow, AGU Fall Meeting Abstracts, pp. B33D-1575.

Lloyd, J., Taylor, J.A. (1994) On the temperature dependence of soil respiration. Functional Ecology 8, 315-323.

Premrov, A., (2024) miniRECgap. R package  with GUI suported scripts for gap-filling the of Eddy Covariance CO2 flux data.  Copyright: Trinity College Dublin. URL:  'miniRECgap package will be uploaded on GitHub in near future'.

Rabinowitch, E.I. (1951) Photosynthesis and Related Processes. Interscience Publishers.

How to cite: Premrov, A., Yeluripati, J., and Saunders, M.: Introducing the ’miniRECgap’ package with GUI-supported R-scripts for simple gap-filling of Eddy Covariance CO2 flux data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6475, https://doi.org/10.5194/egusphere-egu24-6475, 2024.

The AquaCrop model is a powerful tool for crop monitoring, providing a daily estimation of soil-crop-atmosphere dynamics. The model requires a substantial number of input variables and parameters, highlighting the need for identifying those that significantly influence model outputs. Sensitivity analysis is a vital method for this purpose. A key objective of this study is to examine the performance of the AquaCrop model in simulating wheat yield and irrigation water requirement in drylands under two scenarios: first running the model employing a minimal amount of in situ data, and second using all available in situ data. A second focus is to analyze the sensitivity to all crop and soil related input variables and parameters. To do this, a pilot-scale study was undertaken, focusing on a commercial farm in the Al-Jouf province of Saudi Arabia. The farm comprised 200 center-pivot fields of mainly wheat crops. In situ data was collected to calibrate the model for two consecutive growing seasons (2019-2020 and 2020-2021). Using the variance-based Sobol technique, the sensitivity of the AquaCrop model outputs, particularly wheat yield and irrigation water requirement, to crop and soil related input variables and parameters was examined, as were the influential and non-influential inputs on these outputs. Results showed that the second scenario (all data) outperformed the first (minimal data), demonstrating more accurate wheat yield predictions with rRMSE values of 17% and 21% for the 2019-2020 and 2020-2021 growing seasons, respectively. Regarding irrigation water requirement estimations, the second scenario also exhibited lower rRMSE values of 20% and 19% for the same growing seasons. Results also demonstrated that the sensitivity indices of variables and parameters varied with model outputs and growing seasons. By synthesizing inputs sensitivities under different conditions, the influential input variables and parameters were distinguished. Overall, six variables and parameters held significant influence on the analyzed model outputs based on their total-order sensitivity indices. These included duration from sowing to senescence (senescence), duration from sowing to harvesting (maturity), duration from sowing to yield formation (HIstart), base temperature below which growth does not progress (Tbase), minimum air temperature below which pollination failure begins (Tmin_up), and shape factor describing reduction in biomass production (fshabe_b). It was revealed that most variables and parameters were non-influential, which might allow them to be fixed within their ranges to optimize model calibration. The research represents the performance assessment and sensitivity analysis of the AquaCrop model over a desert farming system and offers guidelines for model calibration by delivering information on influential and non-influential input variables and parameters.

How to cite: Almalki, A. S., El Hajj, M. M., Johansen, K., and McCabe, M. F.: A Comprehensive Assessment of the AquaCrop Model in drylands: Performance Examination and Sensitivity Analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6832, https://doi.org/10.5194/egusphere-egu24-6832, 2024.

Accurately quantifying carbon dynamics in peatlands is critical to assess their role in regulating global climate. Within hotspots of peatland degradation, such as in Europe and South-east Asia, skilful assessment of the spatial and temporal impacts of climate change and different land management options is required to meet emissions reductions targets and improve regional management planning.

To address this challenge, a random forest-based metamodel was evaluated to assess its utility in simulating various greenhouse gas (CO₂) emission components, including Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), and Ecosystem Respiration (ER) across two Scottish peatlands. The metamodel mimicked the complex Wetland-DNDC model at a higher level of abstraction with increased efficiency and lower computational time.

While Wetland-DNDC also simulates NEE, GPP and ER, it typically involves a considerable number of parameters related to soil properties, climate data, vegetation characteristics, biogeochemical processes, hydrology, nutrient cycling, and microbial activity. Many of these parameters (more than 100) are challenging to measure in the field, and literature values are often adopted, which may not necessarily reflect local site conditions. In essence, this multidimensional parameter space introduces high uncertainties in modelling carbon fluxes.

In contrast, random forest-based metamodel preserved the key relationships between NEE and input variables (air and soil temperature, water table, precipitation, vegetation, and soil properties) as described in the Wetland-DNDC model with lower parameter requirements (less than 20) and increased accuracy. Similar unique relationships were established for GPP and ER. The random forest-based metamodel represented the Wetland-DNDC model  within the spectrum of input values and parameters across which it was simulated.

The simulation was conducted in two locations across Scotland with contrasting contemporary carbon dynamics: a near natural blanket bog in Cross Lochs, Forsinard, currently functioning as a resilient net carbon dioxide sink (UK-CLS; Lat. = 58.37, Long. = -3.96; altitude = 207 m) and an eroding oceanic blanket bog located in the Cairngorms, currently net emitting carbon dioxide (UK-BAM; Lat. = 56.92, Long. = -3.15, altitude = 642 m). The simulation was validated against eddy covariance flux measurements under varying climate conditions.

In contrast to Wetland-DNDC (R2 = 0.43), the metamodel provided a much-improved fit to the 1:1 line for NEE (R2 = 0.83). Model accuracy was slightly lower for the former (RMSE = 0.72) compared to its metamodel version (RMSE = 0.699). Similar trends were observed for GPP and ER simulations. At a monthly resolution, Wetland-DNDC-derived NEE, GPP, and ER consistently deviated by more than 20% from the eddy covariance-derived estimates, whereas its metamodel version showed deviations of less than 10%. Currently, work is in progress to incorporate management and drought simulation within a metamodel framework, as well as to upscale carbon fluxes from tower to landscape resolution.

The simulation of carbon fluxes using the metamodel-based approach holds the promise of enhancing emission reporting to Tier 3 standards and offers a hopeful avenue for modelling carbon dynamics in peatlands.

How to cite: Mitra, B., Yeluripati, J., Cash, J., Toca, L., Coyle, M., and Artz, R.: Metamodel simulation of carbon fluxes across an eroding and pristine blanket bog in Scotland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8466, https://doi.org/10.5194/egusphere-egu24-8466, 2024.

Soil compaction is an important physical characteristic that affects agricultural productivity by increasing soil density, which reduces the volume of a given soil mass. Due to the higher compaction, plant roots find resistance in penetrating deeply into the soil, limiting their access to essential nutrients and moisture, impacting the plant health with lower levels of N, P and K, resulting in lower productivity. Soil compaction can also reduce soil porosity, aeration, carbon mineralisation/sequestration and increasing the production of greenhouse gases through denitrification in anaerobic sites. Besides that, soil compaction can cause surface runoff and erosion, increasing the risk of flooding and soil loss. A partial recuperation of compacted soils is an expensive and labour-intensive task. In addition, agricultural land expansion for crops is limited. Hence, mapping agricultural areas at risk of soil compaction is essential to implement strategies to mitigate the adverse effects of soil compaction.

Soil particle size and soil drainage were used to classify topsoil's (T) compaction risk class. For subsoil (S) soils (after horizon A), the subsoil particle size, packing density (bulk density + 0.009 * clay (%)), soil drainage and field capacity days were used to estimate the compaction risks. The main problem of this strategy is that these analyses are expensive and time-consuming, i.e., soil particle size analysis requires an average time of 1 month per 100 samples and costs ~ 40.00 per sample. Bulk density analysis costs ~ € 7.00 per sample and is also time-consuming; consequently, bulk density values are mainly predicted using pedo-transfer functions in mapping studies.

To speed up the analysis and minimise the costs, vibrational spectroscopy combined with chemometrics was used to determine soil particle size and bulk density. Both parameters were combined with field capacity days (obtained from 104 national wide meteorological stations) and drainage class (obtained from Irish - Environmental Protection Agency) to map soil compaction risk areas in the northern half of the Republic of Ireland with a resolution of 4 km² (2x2km) and 1 km² grid for regional and periurban regions, respectively (Tellus achieve). To confidentially map these regions, spectral control charts based on PCA were used to identify unrepresentative sample spectra based on the spectral models used. Only samples classified as representative were predicted by the spectral models. Using this strategy, we could predict ~ 90% (T) and ~66% (S) compaction risks in non-peat soils. The prediction results showed that ~33% (T) and ~43% (S) were classified as high risks of compaction, ~19% (T) and ~23% (S) as moderate, and ~37% (T) and <1% (S) as low risks or other classes.

How to cite: de Santana, F., Hall, R., Shi, L., Lowe, V., Hodgson, J., and Daly, K.: MIR spectroscopy combined with meteorological data can estimate soil compaction risks in top and subsoils., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10001, https://doi.org/10.5194/egusphere-egu24-10001, 2024.

In the framework of the NewLife4Drylands LIFE Preparatory project (LIFE20 PRE/IT/000007, 2021-2024) the estimation of SDG 15.3.1 indicator [1], adopted in the UNCCD’s Good Practice Guidance [2], was applied for evaluating Land Degradation (LD) in different Mediterranean Protected Areas (PA). To effectively support PAs managers, joint effort was made in the evaluation of SDG 15.3.1 indicator at the local scale by using satellite Remote Sensing data in the computation of the three main sub-indicators as trend in Land Cover (LC), Primary Production (PP) and Soil Organic Carbon (SOC) stock. Where feasible, local scale sub-indicators were not sourced from open-access global/European databases due to their lack of accuracy at the site scale [3]. LD was estimated not only for the whole PA but also for specific LC classes of interest, considering additional sub-indicators related to pressures and threats affecting the class. This study focuses on the dryland Alta Murgia (IT9120007) PA, in southern Italy, and the wetland Nestos River Delta (GR1150001) PA, in Greece. For Alta Murgia site, featuring semi-natural dry grassland habitats of community interest that are frequently subjected to fire events during the summer season, the Burn Severity (BS) index was included. BS trends were measured by assessing the difference in pre/post–fire Normalized Burn Ratio (NBR) index from Landsat data during summer. Baseline data from 2004, coinciding with the establishment of a National Park within PA, was compared with 2018 for validating field data availability. Nestos River Delta hosts the largest natural riparian forest in Greece and is frequently subjected to hydrological cycle modifications, involving water scarcity due to both inappropriate river management and climate change, in turn hampering the transport of nutrient-rich sediments and the enrichment of soils being at risk of aridification. Within this framework, Hydroperiod and Soil Salinity indices were considered for LD and specific impacts on aquatic vegetation LC. Baseline data from 2017, after the dry climate conditions of 2016-2017, was compared with 2021 for validating field data availability. Both in Alta Murgia and Nestos, LC mappings were obtained by a data-driven pixel-based approach considering Landsat/Sentinel-2, respectively, multi-seasonal imagery and a multi-class Support Vector Machine (SVM) classifier trained with data from in-field campaigns and historical orthophotos interpretation. Time series of MSAVI from Landsat (which replaced standard NDVI for its soil correction benefits [4]) and PPI from Sentinel-2 by Copernicus services, respectively, were used to track grassland PP trends. Lastly, for SOC stock trends, the open-source Trends.Earth QGIS plugin [5], incorporating customized LC data and global SoilGrids product, was adopted to supplement local data limitations. According to its specification, the SDG 15.3.1 indicator was computed by integrating all the sub-indicators according to the principle “one out, all out” obtaining the 3-classes output mapping (Degradation, Improvement, Stable). The findings can support the monitoring and evaluation of LD, guiding protective measures aligned with the Agenda 2030 for Sustainable Development. They, also, highlight the importance of the integration of local scale data and sub-indicators within the UNCCD methodology.

References

[1] https://unstats.un.org/sdgs/metadata/files/Metadata-15-03-01.pdf

[2]https://www.unccd.int/publications/good-practice-guidance-sdg-indicator-1531-proportion-land-degraded-over-total-land

[3] https://doi.org/10.3390/rs13020277

[4] https://doi.org/10.3390/rs12010083

[5] http://trends.earth/docs/en

How to cite: Tarantino, C., Aquilino, M., Vicario, S., Labadessa, R., Cambria, V. E., Georgiadis, C., Vitale, M., Assennato, F., and Mazzetti, P.: SDG 15.3.1 indicator at local scale for monitoring land degradation in protected areas, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10906, https://doi.org/10.5194/egusphere-egu24-10906, 2024.

Agricultural system models are widely recognized as valuable tools for identifying best management practices and addressing the challenges posed by climate change. In this context, the use of model ensembles has been recently recommended for their enhanced performance and accuracy. However, assessing their effectiveness over a large geographical area, such as national scale is often currently lacking. This study focuses on simulating soil organic carbon (SOC) dynamics using an ensemble of models comprising DSSAT, CropSyst, EPIC, and APSIM models, utilizing data derived from five Long-Term Experiments (LTEs) spread across a north-to-south pedoclimatic range transect in Italy. This region is of particular importance as it represents a significant hotspot for climate change. The LTEs featured a robust array of 63 unique experimental protocols, incorporating variation effect in fertilization rates, cropping rotations, and tillage prescriptions. This resulted in a total of 2184 years of simulated data for each model. The dataset employed included SOC stocks and crop yield and biomass. Models underwent independent calibration, with crop and SOC parameters selected based on expert knowledge. Main crop cultivars, such as maize, soybean, sugarbeet, and wheat, were further categorized and calibrated by maturity classes. A similar approach was used for cover crops. The extensive dataset enabled a nuanced exploration of the models’ performance across varied agro-ecological contexts. The models proved capable of accurately reproducing the varied pedo-climatic conditions of the Italian peninsula, contributing to the advancement of our understanding of SOC dynamics.

How to cite: Longo, M., Piccoli, I., Berti, A., Farneselli, M., Tabaglio, V., Ventrella, D., Trestini, S., and Morari, F.: Exploring soil organic carbon dynamics through a multi-model simulation of multiple long-term experiments , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11219, https://doi.org/10.5194/egusphere-egu24-11219, 2024.

Long-Term Field Experiments (LTEs) are agricultural infrastructures for studying the long-term effects of different management practices and soil and crop properties in changing climate conditions. These experiments are essential to examine the impact of management and environment on crop production and soil resources on different soil textures and types. Some of those LTEs have average times of 20-50 years, even more than 100 years. These infrastructures are thus scientific heritages with high values of agricultural data; however, LTE-related information was difficult to find since it was scattered. To close this gap, we developed a geospatial data infrastructure, including an LTE overview map to compile and analyze the meta-information of the LTEs across Europe. The map provides a spatial representation of LTEs and the meta-information, collected by extensive literature review and factsheets in collaboration with BonaRes and EJPSoil projects, clustered in different categories (management operations, land use, duration, status, etc.) (Grosse et al. 2021; Donmez et al., 2022; Blanchy et al., 2023; Donmez et al., 2023). A threshold filter with a minimum duration of 20 years was applied, which results in a total of 500 LTEs across Europe and included into the map. The clusters of LTEs were geospatially analyzed to provide inputs for the agricultural sector, scientists, farmers and policy-makers. The fertilization treatment was the major research theme of collected and studied LTEs, followed by crop rotation and tillage trials. Bringing the meta information of dispersed LTEs through the development of the LTE overview map is expected to help developing a mutual management framework of efficient agricultural production by revealing the LTE potential internationally. This will contribute to scaling up the agricultural practices from site to landscape level for increasing the climate change adaptation to agricultural yield and management.

References

Donmez C., Schmidt M., Cilek A., Grosse M., Paul C., Hierold W., Helming K., (2023): Climate Change Impacts on Long-Term Field Experiments in Germany. https://doi.org/10.1016/j.agsy.2022.103578. Vol.205, 103578. Agricultural Systems.

Blanchy G., D’Hose T., Donmez C., Hoffmann C., Makoschitz L., Murugan R., O’Sullivan L., Sanden T., Spiegel A., Svoboda N., Boltenstern S.Z., Klummp K., (2023): An open-source database of European long-term field experiments. https://doi.org/10.1111/sum.12978  Soil Use and Management

Donmez C., Blanchy G., Svoboda N., D’Hose T., Hoffmann C., Hierold W., Klummp K., (2022): Provision of the metadata of European Agricultural Long-Term Experiments through BonaRes and EJP SOIL Collaboration. Data in Brief. https://doi.org/10.1016/j.dib.2022.108226.

Grosse, M., Ahlborn, M.C., Hierold, W. (2021): Metadata of agricultural long-term experiments in Europe exclusive of Germany. Data in Brief 38, https://doi.org/10.1016/j.dib.2021.107322

How to cite: Donmez, C., Hoffmann, C., Svoboda, N., D'Hose, T., Specka, X., and Helming, K.: A Geospatial Overview of Agricultural Long-Term Field Experiments across Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11605, https://doi.org/10.5194/egusphere-egu24-11605, 2024.

The proposal for the European Soil Monitoring Law includes an integrated value of soil water holding capacity to be determined as a proxy for soil quality for whole soil districts. As this is a relatively new but interesting approach, a number of details of the assessment procedure remain open at the current stage of formulation. The aim of this study is to quantify the effects of the choice of different options on the overall result, focusing on the delineation of soil districts in different sizes, the detailed definition of the respective soil property, and the treatment of sealed areas.

High-resolution data for soil hydrological properties for two Austrian provinces are used as a basis, including different approaches to calculate soil water holding capacity. The size of the study area corresponds to the maximum size of a soil district as proposed. Thus, a variation of three size levels is possible, namely the whole area, major river catchments, and agro-geographical sub-units. The term soil water holding capacity is basically defined in the proposed EU Directive, but several options for its determination are possible. We used two different pedotransfer functions to derive soil water holding capacity values and an additional method based on averaging results from randomly located sampling points. Soil sealing is a major threat to hydrological soil functionality, and its assessment over large areas is still not standardized. Here, the European LUISA land use/land cover dataset for 2020 (1 km resolution) and a national dataset with higher resolution are used. Both datasets are optionally overlaid with the Copernicus imperviousness layer involves gradual information about surface imperviousness.

By combining all these factors with each other, different ways were evaluated to determine the target value of soil water holding capacity integrated on a regional scale. Differences in the results and their sensitivity to input variations are quantified to inform policy decisions in the implementation of the European Soil Monitoring Law in the member states.

How to cite: Weninger, T., Schwaighofer, I., Darmann, F., Brunner, T., and Strauss, P.: Soil water holding capacity as descriptor of soil health at district scale – a sensitivity study, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12129, https://doi.org/10.5194/egusphere-egu24-12129, 2024.

Soil erosion constitutes an increasing threat to soil productivity and food security. This work describes the potential of using Artificial Neural Networks (ANN) for upscaling soil loss outputs from medium to low scale. The Revised Universal Soil Loss Equation (RUSLE) model was implemented to calculate soil loss rates in two scales in Crete, Greece. Specifically, the RUSLE model was applied in six (6) watersheds across the island using medium spatial resolution satellite images (5m), namely Planetscope. These results were used to feed an ANN model to upscale the mesoscale outputs (5m) to regional outputs (30m-island level). The ANN system was trained using spatial environmental parameters such as the Normalized Difference Vegetation Index, Digital Elevation Model, and topographical slope angle. This "optimized" soil loss derivative later made it possible to compare it with the corresponding final derivative of Crete (regional spatial scale), which emerged from the straightforward processing of RUSLE model with the more "coarse" and generalized data as estimated from the  Landsat-8 satellite images (30m). The statistics revealed that the detailed and high-quality soil loss data, as derived from the upscaling process, provide more precise and reliable results.

How to cite: Alexakis, D. D. and Polykretis, C.: Using Artificial Neural Networks to upscale soil erosion model results from local to regional scale. An example from Crete, Greece., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14678, https://doi.org/10.5194/egusphere-egu24-14678, 2024.

The necessity of soil health monitoring is paramount in reversing soil degradation and promoting sustainable farming. Including cover crops in the crop rotation is one of the sustainable soil management practices contributing to soil health. Cover crops contribute to soil health by nutrient retention and carbon accumulation during their growth and return of organic matter to the soil upon their incorporation. During monitoring, the sampling frequency can change from annual in the case of SOC to weekly or daily for fertilization and irrigation. Remote sensing techniques offer a solution, enabling the monitoring of vegetation over time and space, thereby enhancing our understanding of the impact of cover crops on the main crop. However, this technology makes it possible to see the surface of the field which can assist with the above-ground changes of the system. Process-based modelling and data assimilation can subsequently link the above-ground component with soil functions. In-situ data collection that includes crop characteristics such as biomass and N-uptake is essential both for transforming remote sensing data into crop characteristics and for calibrating models. Using Unmanned Aerial Vehicles (UAVs) can potentially collect data at high frequency, which can be used to enhance soil process modelling. The development of this UAV-based method has the potential to be scaled up to a satellite level in the future.

In our research, we have combined the study of nutrient cycling and the effect of cover crops on soil health. To achieve this, we have used the WOFOST-SWAP-ANIMO model to simulate the varying influence of cover crop monocultures and mixtures on Soil Organic Carbon (SOC) and Nitrogen cycling in a 7-year crop rotation on sandy soil. The model simulates vegetation characteristics such as biomass, leaf area index, and yield, as well as soil moisture and mineral Nitrogen concentrations. This will give us a good estimation of the vegetation input into the soil as well as the nutrient uptake from both cover crops and main crops. Soil sampling is also important to model calibration/validation to be able to simulate the N dynamics of biological activity under the surface. Our findings suggest that the model, in conjunction with UAV data and field sensors, can effectively monitor soil health indicators crucial for field management practice selection, such as the Carbon cycle and Nitrogen use efficiency.

How to cite: Vavlas, N.-C., Kooistra, L., van Egmond, F., and De Deyn, G.: Integrating UAV data and soil-crop modelling for Enhanced Soil Health Monitoring, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15537, https://doi.org/10.5194/egusphere-egu24-15537, 2024.

Preserving soil health and enhancing the ecosystem services that soil produces is of primary importance in European strategies and policies. More than 60% of the European soils are unhealthy due to unsustainable land use, pollution, climate change, and extreme events. This causes loss of ecosystem services, costing the EU at least €50 billion annually. Collaboration among businesses, policymakers, public administration, and the scientific community is crucial to develop practices that recognize the essential role of soils in sustaining livelihoods, biodiversity, and climate regulation.

In this framework, the Horizon Europe funded project InBestSoil (https://inbestsoil.eu/) aims to co-create a framework for investments in soil health preservation and restoration by developing a system for the economic valuation of the ecosystem services provided by healthy soil and the impacts of soil interventions, and its incorporation into business models and incentives. To achieve this, InBestSoil has selected 7 existing Soil Health Lighthouses (LHs) and 2 Soil Health Living Labs (LLs, in different maturity stages) covering four land uses (agricultural, forestry, urban, mining) across four biogeographic regions over Europe. The LLs are collaborative initiatives focused on co-creating knowledge and innovations, while LHs represent individual sites known for exemplary performance. The LL1, located in Sardinia (Italy), is coordinated by the CMCC Foundation and Agris Sardegna Research Agency. It focuses on Mediterranean agricultural soils and aims addressing the challenges related to climate change and extreme events, soil pollution, land abandonment, and water scarcity. It includes 2 LHs on conservation agriculture managed by Agris and 9 Living Lab Experimental Sites (LLES), which evaluate the introduction of sustainable soil practices. The LHs included in the LL are two Long-Term Experiments (>20 years) on conservation agriculture (reduced and no tillage versus conventional tillage) on durum wheat in rotation with legumes, in soils with different fertility levels that are representative of Mediterranean cereal farming conditions. Conservation agriculture is among the most promising climate-smart agricultural practices because it contributes to both climate change mitigation and adaptation objectives while helping to maintain and increase farmers' incomes. However, it is important both to acquire additional information to assess the medium- to long-term effects of these practices in different environments and cropping systems as well as to disseminate the scientific evidence and support the wider application of these practices in the Mediterranean region.

The LHs aim to provide scientific evidence and disseminate knowledge and experience gained in the long-term application of conservation agriculture in Mediterranean agricultural systems.  Moreover, in the selected 9 LLES, located in different areas and including cereal, olive tree and vineyard farms, soil samplings and analyses are being conducted to measure soil indicators and provide information to assess the economic evaluation of ecosystem services provided by soils managed with sustainable agricultural practices, primarily including conservation agriculture.

We aim to create a permanent space of discussion on the topic of soil health, involving all relevant actors, from farmers to researchers to policy makers, in order to identify common solutions and innovations that can face the economic and environmental challenges the Mediterranean agriculture is facing.

How to cite: Mereu, V., Carboni, G., Menini, A., Canu, M., Dettori, M., Urracci, G., and Marras, S.: Empowering soil health in Mediterranean environments through collaborative stakeholder engagement: insights from Sardinian Living Lab of the InBestSoil project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18038, https://doi.org/10.5194/egusphere-egu24-18038, 2024.

Mountain grasslands play a pivotal role in delivering both economic and cultural ecosystem services, including food production, carbon sequestration, the provision of clean water, and preserving local traditions. However, these ecosystems are facing increasing threats from climate change around the world. Among the main challenges is the intensification of extreme precipitation events. They can aggravate the process of soil erosion and trigger landslides in mountain grasslands, with possible negative consequences on both ecosystems and human activities. However, the high variability of these ecosystems, as well as their wide distribution, makes it complex to adequately map their locations and investigate possible soil erosion hotspots, especially under future scenarios with varied rainfall regimes. In this context, the use of remote sensing technologies and modeling approach could open new frontiers to investigate critical areas and therefore guide mitigation solutions. The satellite Earth Observation (EO) through international space missions, coupled with cloud-based data analysis platforms like Google Earth Engine (GGE), facilitates ecosystem mapping at a resolution and frequency previously inaccessible. Furthermore, the utilization of multi-temporal models for potential soil erosion analysis in present and future scenarios can enhance our understanding of erosion dynamics attributed to climate change. In this research, we first map at high resolution the global mountain grasslands distribution taking advantage of Sentinel-based EO’s products. In such locations, we evaluate the multi-temporal soil erosion dynamics caused by water employing diverse climate scenarios (RUSLE model; 2015 vs. 2070-RCP8.5). Our findings indicate a potential global escalation in soil erosion within mountain grasslands, notably in South America and Africa, alongside identifiable localized hotspots. Remote sensing-based research paired with a modeling approach aimed at mapping critical areas and analyzing environmental challenges in ecosystems is therefore imperative. Such investigations not only delineate vulnerable regions but also guide targeted solutions crucial for safeguarding these ecosystems and their ecosystem services in the face of climate change.

How to cite: Straffelini, E., Luo, J., and Tarolli, P.: Satellite-based remote sensing and multitemporal modeling approach for mapping soil erosion hotspots in global mountain grasslands under climate change, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18161, https://doi.org/10.5194/egusphere-egu24-18161, 2024.

Peatland restoration and rehabilitation action has become more widely acknowledged as a necessary response to mitigating climate change risks and improving global carbon storage. Peatland ecosystems require restoration timespans on the order of decades and thus cannot be dependent upon the shorter-term monitoring often carried out in research projects. Hydrological assessments using geospatial tools provide the basis for planning restoration works as well as analysing associated environmental influences. “Restoration” encompasses applications to pre- and post-restoration scenarios for both bogs and fens, across a range of environmental impact fields. A scoping review was carried out to identify, describe, and categorise current process-based modelling uses in peatlands in order to investigate the applicability and appropriateness of eco- and/or hydrological models for northern peatland restoration. Two literature searches were conducted using the Web of Science entire database in September 2022 and August 2023. Of the final 211 papers included in the review, models and their applications were categorised according to this review’s research interests in 7 distinct categories aggregating the papers’ research themes and model outputs. Key themes emerging from topics covered by papers in the database included: modelling restoration development from a bog growth perspective; the prioritisation of modelling GHG emissions dynamics as a part of policymaking; the importance of spatial connectivity within or alongside process-based models to represent heterogeneous systems; and the emerging prevalence of remote sensing and machine learning techniques to predict restoration progress with little physical site intervention. Based on this assessment, CoupModel, DigiBog, and MPeat2D were calibrated for the case of Abbeyleix Bog, Co. Laois, Ireland (ongoing with results expected before April 2024). The exploration of subsequent simulations to represent varying peatland restoration conditions is discussed from an ecohydrological lens.

How to cite: Silva, M.: Ecohydrological modelling on peatlands: scoping review and application of three process-based models to Irish raised bog restoration, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18533, https://doi.org/10.5194/egusphere-egu24-18533, 2024.

Carbon use efficiency has recently been proposed as a central parameter that promotes soil organic carbon storage based on data assimilation with a global soil organic carbon database and a vertical, microbial explicit soil organic carbon model (Tao et al., 2023). In this research, we present a sensitivity study with a vertical soil organic carbon model, COMISSION v2.0 (Ahrens et al., 2020), that not only models microbial interactions explicitly but also represents organo-mineral interactions with a maximum capacity, Q_max, to form mineral-associated organic carbon (MAOC).

The COMISSION model represents the formation of MAOC from microbial necromass and dissolved organic carbon analogous to Langmuir sorption. Empirical studies have provided Q_max parameterizations derived from quantile or boundary line regressions with clay and silt content. For the sensitivity study, we vary Q_max along the full range of observed Q_max values while simultaneously varying carbon use efficiency (CUE). Our results highlight that CUE and Q_max promote soil organic carbon storage to similar degrees along their respective observed ranges. The remaining parameters of the COMISSION model were kept at their calibrated values from a multi-site calibration with soil organic carbon, mineral-associated organic carbon, and radiocarbon profiles (Ahrens et al., 2020). While Q_max and CUE are of similar importance for promoting soil organic carbon storage, they also interact in promoting SOC storage. Higher Q_max values strengthen the promotion of soil organic carbon storage with higher CUE. This positive interaction results from higher microbial necromass with higher CUE and the subsequent association of microbial necromass on mineral surfaces mediated through Q_max. The sensitivity study revealed that CUE is the dominant driver for microbial biomass levels. Q_max affects microbial biomass only to a small degree through 'competition' between mineral surfaces and microbial biomass for dissolved organic carbon. While the effect of Q_max on microbial biomass is small, the relationship between Q_max and microbial biomass is generally negative. At the lower end of the tested range of carbon use efficiencies (CUE < 0.15), further model experiments reveal that imposing a stronger microbial limitation of depolymerization can lead to a negative relationship between CUE and soil organic carbon storage.

Overall, our results highlight that in soil organic carbon models with microbial interactions and a limited capacity to form organo-mineral associations, both processes can be of similar importance in promoting soil organic carbon storage. The current debate in the observational realm, whether there is indeed an upper limit for mineral-associated organic carbon formation, can spark a similar debate in the modeling realm on how to represent mineral-associated organic carbon formation in models mechanistically.

References

Ahrens B, Guggenberger G, Rethemeyer J et al. (2020) Combination of energy limitation and sorption capacity explains 14C depth gradients. Soil Biology and Biochemistry, 148, 107912.

Tao F, Huang Y, Hungate BA et al. (2023) Microbial carbon use efficiency promotes global soil carbon storage. Nature, 618, 981-985.

Funding acknowledgment: Bernhard Ahrens has received funding through the AI4SoilHealth project. The AI4SoilHealth project has received funding from the European Union's Horizon Europe research and innovation programme under grant agreement No. 101086179.

How to cite: Ahrens, B. and Chettouh, M. A.: Carbon use efficiency and mineralogical capacity are of similar importance for promoting soil organic carbon stocks, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18844, https://doi.org/10.5194/egusphere-egu24-18844, 2024.

Integrated crop-livestock (ICL) systems can have a complex of effects on soil properties that can influence greenhouse gas emissions (GHG). The ICL aim to capture atmospheric CO₂ and sequester it in the soil, holding promise for reducing GHG emission intensity from livestock products. Moreover, modeling N₂O emissions can help assess the potential impact of N management on the ICL system to optimize the sustainability of agriculture production. Field data were obtained from an ICL experiment of EMBRAPA-Rice and Beans, located on Capivara farm, Santo Antônio de Goiás/GO, Brazil (16°28´S; 49°17´W; 823 m alt.). The ICL experiment was evaluated for four years (2013-2016) with the following crop rotation sequence: pasture-fallow-maize, fallow-soybean, maize-fallow-maize, and beans-fallow. The N₂O data was obtained from the 2013-14 season, which was measured in a static chamber during maize cultivation. The experiment consisted of 9 treatments (N sources and rates) with 5 replicates. The N₂O was measured in 30 sampling events over almost 100 days. The daily N₂O fluxes from the treatments control (No N), urea (UR), calcium ammonium nitrate (CAN), and ammonium sulfate (AS) at an N rate of 150 kg/ha were used to parametrize the DNDC. Model crop and soil parameters were adjusted to better simulate maize production and N₂O emission according to observed data. DNDC simulated CO₂ emissions, quantified as Net Ecosystem Exchange (NEE), were validated against CO₂ emissions derived from eddy-covariance data, using statistical parameters such as R², RMSE, MAE, and Bias. While data refinement is ongoing, preliminary findings indicate that DNDC shows promise for estimating CO₂ emissions IPS under tropical conditions The DNDC had a satisfactory performance in predicting N₂O emission in the ICL system, resulting in a significant correlation with the observed data (r = 0.63, p < 0.001), MAE of 0.024, and RMSE of 0.036. The average daily N₂O-N emission observed was 0.026 kg ha^-1 day^-1 and simulated was 0.025 kg ha^-1 day^-1. The UR, CAN and AS applications showed a peak of N₂O emission on 31^th day after sowing (2 days after fertilization) corresponding to 0.175, 0.217, and 0.163 kg ha^-1 day^-1, respectively, where the model simulated N₂O peaks of 0.151, 0.123, and 0.173 kg ha^-1 day^-1. The accumulated N₂O emissions were 0.513, 1.148 1.738, and 0.890 kg ha^-1 for control, UR, CAN, and AS respectively, in which the simulated by DNDC were 0. 778, 1.612, 1.391, and 1.755 kg ha^-1. In general, the model had a good fit with daily N₂O emissions, but it tended to overestimate the N₂O emission from UR and AS, and underestimate from CAN. Further model parametrization and calibration may be necessary to better predict N₂O and CO₂ emissions. The DNDC satisfactory simulated the N₂O emissions from different N sources applied to ICL system, which can be used to evaluate the potential emissions and mitigation according to N management in ICL.

How to cite: Matos, P. S., Soares, J. R., Carvalho, M. C. S., Madari, B. E., Alves, B. J. R., Jantalia, C. P., Freitas, A. C. R., Mitraa, B., and Yelupirati, J.: Performance of the DNDC in Estimating CO 2 and N 2 O emissions of Integrated Crop-Livestock Systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19814, https://doi.org/10.5194/egusphere-egu24-19814, 2024.

The Horizon Europe project LOESS ‘Literacy boost through an Operational Educational Ecosystem of Societal actors on Soil health’ officially started in June 2023 involving twenty partner organizations in fifteen countries across Europe, lead by the WILA Bonn Science Shop. The final goal of the project is to raise awareness on the importance of soil and of its functions and to increase soil literacy across Europe. To do so, the first step of the project activity is designed to map and connect multiple actors in Communities of Practice (CoPs) at the national level, and engage them to provide an overview of the current level of soil related knowledge and teaching programmes and materials, in order to identify the gap between this material and the educational needs amongst different levels of the society (from pupils to students to citizens).

The Italian chapter is led by two university research groups with different expertise (civil and environmental engineering at the University of Brescia on one hand and social sciences at the University of Sassari on the other) and one NGO (Controvento) whose mission is children not-formal education. The Italian CoP, led by the University of Brescia, is composed of 62 members from both the higher education and the research community, as well as from the primary and secondary education levels (teachers and pupils), from the productive sectors (farmers and spatial planners), from the politics world (local administrators) and from the civil society (NGOs and associations).

This contribution presents the activities performed so far, viz the stakeholder mapping, the creation of the CoP and its first meetings and the community-based participatory activity which was organized on the World Soil Day 2023.

How to cite: Peli, M., Dada, A., Barisani, F., Ventura, V., Pezzagno, M., Barontini, S., and Grossi, G.: The LOESS project to boost soil health literacy across Europe: The case of Italy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19820, https://doi.org/10.5194/egusphere-egu24-19820, 2024.

Soil health is a key concept in worldwide efforts to reverse soil degradation, but to be used as a tool to improve soils, it must be definable at a policy level and quantifiable in some way. Soil indicators can be used to define soil health and quantify the degree to which soils fulfil expected functions. Indicators are assessed using target and/or threshold values, which define achievable levels of the indicators or associated soil functions. However, defining robust targets and thresholds is not a trivial task, as they should account for differences in soil type, climate, land-use, management, and history, among other factors.

We assessed (through theory and stakeholder feedback) four approaches to setting targets and thresholds: fixed values based on research, fixed proportions of natural reference values, values based on the existing range (e.g. lower quartile of the observed distribution), and targets based on relative change (e.g. a 20% increase of the indicator’s value). Three approaches (not including relative change) were then further explored using case study examples from Denmark, Italy, and France, which highlighted key strengths and weaknesses of each approach. Here, we present a selection of the assessment and case study results, as well as a framework, which facilitates both choosing the most appropriate target/threshold method for a given context, and using targets/thresholds to trigger follow-up actions to promote soil health.  

How to cite: Matson, A., Fantappiè, M., Campbell, G. A., Miranda-Vélez, J. F., Faber, J. H., Gomes, L. C., Hessel, R., Lana, M., Mocali, S., Smith, P., Robinson, D., Bispo, A., van Egmond, F., Keesstra, S., Saby, N. P. A., Smreczak, B., Froger, C., Suleymanov, A., and Chenu, C.: A framework for setting soil health targets and thresholds in agricultural soils , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20664, https://doi.org/10.5194/egusphere-egu24-20664, 2024.

In the context of recycling organic waste products or irrigation by treated wastewaters (re-use), the fate of human and veterinary pharmaceuticals in agricultural soils and consequent ground-water contamination are influenced by many factors, including soil properties controlling sorption and dissipation processes (Verlicchi et al., 2015, Mejías et al., 2021, Rietra et al., 2022). Sorption coefficients are among the most sensitive parameters in models used for risk assessment. However, for different classes of pharmaceuticals, the variations in sorption among different soil types are poorly described and understood (Kodesova et al., 2015). Here we reviewed sorption parameters for different classes of pharmaceuticals and their variation with selected soil properties. We also evaluated the sorption isotherms for three pharmaceuticals, ofloxacin, tetracycline, diclofenac and a bactericide,  riclocarban and ten soils from temperate and tropical regions, and assessed the impact of soil properties on Freundlich equation parameters Kf and n. Batch experiments were set up adapting OECD protocol and using initial concentration ranges from 5 to 1000 μg/L. For strongly sorbed molecules, namely ofloxacin, tetracycline and triclocarban, there were strong technical constraints for the quantification of equilibrium concentrations by LC-MS-MS. We used this knowledge from both literature review and experimental data to build pedotransfer functions that allow predicting sorption parameters for a wide range of soils. Sorption of ionizable pharmaceuticals was, in many cases, highly affected by soil pH and CEC whereas soil organic matter content remained a driving factor of sorption for neutral molecular forms.

References:
Kodesova, R., et al. (2015) Science of the Total Environment 511, 435–443.
Mejías, C. et al. (2021) Trends in Environmental Analytical Chemistry 30, e00125.
Rietra, R.P.P.J., et al. (2024) Heliyon 10 (2024) e23718.
Verlicchi, P. & Zambello, E., (2015) Science of The Total Environment 538, 750–767

How to cite: Benoit, P., Godard, C., Deschamps, M., Bernet, N., Delarue, G., Serre, V., and Haudin, C.-S.: Searching for pedotransfer functions to predict sorption of pharmaceuticals from soil properties, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21616, https://doi.org/10.5194/egusphere-egu24-21616, 2024.

Plastic production worldwide has increased from 1.5 million tons in 1950 to 390.7 million tons in 2021.1 Nanoplastics (NPTs) have been considered an emergent contaminant entering the environment without any control since they can be formed by the degradation of large-sized plastic inadequately disposed of and considering that only 9% are effectively recycled.2 Just as the NPTs, nanoparticles (NPs) are considered emergent contaminants, and their application in different industrial products raises concern regarding the NPs entering the environment matrices.3 The soil bioaccessibility is an important parameter when considering the contaminants assessment evaluation with biological soil phase, and the study of soil liquid solution, which is called the soil pore water, can elucidate not only the bioaccessibility but also NPTs and NPs mobility, fate, and stability.4 The NPTs’ and NPs’ concentrations in the range of ng L-1 might be a limitation for their evaluation. However, spICP-MS can provide information on size, number concentration, and mass concentration, even in environmental conditions.5 In this study, a typical Brazilian soil used for plant cultivation (Latosol) was employed, and the soil moisture was controlled according to the field capacity determined in advance. Polystyrene (PS) nanoparticles with gold core and silver NPs (AgNPs), considering their abundance in different goods, were used as model nano-contaminants. The soil pore water was collected in two sampling points through a low-pressure lysimetric method using Rhizon® samplers once a week for 45 days of the experiment. In addition, the soil moisture was controlled by monitoring and adding more water to maintain the soil humidity, considering the three field capacity percentages studied. Results showed a downward trend in the number of particles detected in successive collections over time for both nano-contaminants. However, they also demonstrated different behaviours between them. The NPTs were bioaccessible in the pore water after the first days from the beginning of the experiments, and their concentration decreased constantly. At the same time, the NPs presented an inconstant transport through the soil column, gradually becoming bioaccessible. Finally, the concentration proved to be an important and decisive parameter, bringing essential discussion regarding the nano-contaminant's increasing concentration and behaviour in an environmental matrix, demonstrating the necessity to comprehend their interactions with the soil and between each other.

1 S. Maity, R. Guchhait, M. B. Sarkar and K. Pramanick, Plant. Cell Environ., 2022, 45, 1011–1028.
2 P. Zhou, L. Wang, J. Gao, Y. Jiang, M. Adeel and D. Hou, Soil Use Manag., 2023, 39, 13–42.
3 Q. Abbas, B. Yousaf, Amina, M. U. Ali, M. A. M. Munir, A. El-Naggar, J. Rinklebe and M. Naushad, Environ. Int., 2020, 138, 105646.
4 M. Di Bonito, N. Breward, N. Crout, B. Smith and S. Young, in Environmental Geochemistry, Elsevier, 2008, pp. 213–249.
5 J. Jiménez-Lamana, L. Marigliano, J. Allouche, B. Grassl, J. Szpunar and S. Reynaud, Anal. Chem., 2020, 92, 11664–11672.

How to cite: de Andrade, A., Arruda, M. A. Z., Miguel, S., Reynaud, S., and Jiménez-Lamana, J.: Transport and bioaccessibility of nano-contaminants in Brazilian latosol through pore water evaluation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22341, https://doi.org/10.5194/egusphere-egu24-22341, 2024.

Climate driven changes in hydrologic regimes are increasing riverine flood risks in many parts of the world. Societies that have historically relied on structural flood management infrastructure, e.g., levees and dams, may face significant challenges as these types of infrastructure can be expensive and politically difficult to retrofit for non-stationary and uncertain future flood hazards. Hybridizing conventional infrastructure systems with nature-based solutions (NbS) can help communities adapt to non-stationarity and improve flood resilience. However, despite advances in the academic literature, NbS have failed to become mainstream in many societies. The United States (US) is no exception and has an extensive history of engineering rivers with structural systems to support immediate-term economic growth and with limited consideration for non-stationarity. For example, there are thousands of kilometers of continuously leveed river corridors in the US and many of these levees were built as close to river banks as possible to maximize the commercial prospects of flood protected land use. Such levees are relatively sensitive to non-stationarity and the communities they protect are becoming increasingly vulnerable to climate change-driven flooding. Our research focuses on how to bridge the gap between the scientific development of NbS and implementation in professional practice. We are doing so by example, with levee setbacks on America’s longest river -- the Missouri -- and in collaboration with the US’s primary action agency of flood risk management -- the US Army Corps of Engineers. Setbacks are implicitly an adaptation strategy that buffer a community against uncertainty and non-stationarity by providing additional room for floodwater conveyance. Unfortunately, they are fraught with social and political challenges because -- as a form of managed retreat -- they require some community members to relinquish private property rights so that the broader community can have greater flood protection. Critical to bridging the gap between levee setback research and implementation is understanding the performance of setbacks at scale and the development of simple and repeatable methods for designing setbacks to successfully deliver multiple ecosystem services. The most fundamental of which is how to “size” a setback – in other words – how big of a floodplain reconnection is required to achieve a desired improvement in flood protection services? In this talk, we will discuss sizing methodologies for achieving multiple services, as well as practical engineering, social, ecological, and administrative constraints that have arisen in the process of translating NbS research to practice. The example of levee setbacks on American rivers is particularly useful because it affords experimentation with repeatability (given the thousands of kilometers of continuously leveed river corridors) and the spatial scale of reconnection required to achieve multiple benefits (given the massive size of many levees and floodplains). The results of which may be relatable to many engineered river corridors around the world and will hopefully support mainstreaming NbS in other social and political contexts.

How to cite: Chambers, M., Crane, D., van Rees, C., Shudtz, M., Landry, C., Ferreira, S., Nelson, D., Suedel, B., Woodson, B., and Bledsoe, B.: Nature-based solutions for leveed river corridors, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-467, https://doi.org/10.5194/egusphere-egu24-467, 2024.

As urbanization and climate change continue to pose significant challenges for cities worldwide, green roofs (GRs) has emerged as a viable sustainable solution for supporting traditional infrastructure in managing stormwater runoff. Although their hydrological behavior has been sufficiently documented in literature, conflicting results emerge regarding the potential variations in their retention capacity (RC) over the medium and long-term. Based on preliminary investigations, this research aimed at assessing medium-term changes in the hydrological performance of two experimental GRs (GR1 and GR2), further investigating the potential role played by precipitation severity. The GRs, located in Southern Italy and consisting of three layers (vegetation, substrate and drainage), were set up in 2017 and monitored for two operational periods, 2017-2019 and 2022-2023. The measurements gathered between 2017 and 2019 provide valuable insights into the initial performance of the GRs and their ability to retain water during the early years of operation. Data collected in 2022 and 2023 instead reflect the retention capacity of the GRs after a few years of operation. A total of 29 mild precipitation events were collected during both periods and for both GRs, detecting from the monitoring data their cumulative precipitation (P) and runoff (R) with the objective of assessing the RC (RC = 1 - R/P). Based on the preliminary findings, it appears that there is an overall decline in the RC for both GR1 and GR2, without significant differences between the two. The Aging Indexes (AI) were calculated for GR1 and GR2, representing the average reduction of the runoff coefficient (RC) over time. GR1, which has a drainage layer composed of expanded clay, exhibited an AI of 12%. On the other hand, GR2, characterized by a drainage layer made of MODI' plastic panel filled with expanded clay, exhibited a slightly higher AI of 13%. Further analysis revealed that within each dataset, two groups were identified based on a threshold determined by the growth coefficient g(T) of the precipitation events. For the group of events with g(T) values above 0.12 (sample size of 14), the AI values were 15% and 16% for GR1 and GR2, respectively. On the other hand, the group of events with g(T) values equal to or lower than 0.12 (sample size of 15) experienced AI values of 10% and 11% for GR1 and GR2, respectively. These findings suggest that as the growth coefficient g(T) increases, indicating higher return periods T, the AI and consequently the reduction in hydrological performance of GRs also increase. The highly possible increase in the future of extreme precipitations would pose a considerable limit to the spread of this kind of sustainable drainage infrastructures. However, additional modeling investigations focused at detecting the effects of alternative GRs designs and materials on their long-lasting average hydrological performance would be essential for making informed decisions and investments.

How to cite: D'Ambrosio, R. and Longobardi, A.: Assessing the Medium-Term Changes in Hydrological Performance of Green Roofs: The Influence of Precipitation Severity, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1019, https://doi.org/10.5194/egusphere-egu24-1019, 2024.

Nature-based Solutions, even if not identified as such, are becoming more and more popular in land planning, especially in cities. Conserving and restoring green infrastructure in urban context is now recognised as being a good practice in the face of climate change adaptation: ecosystem services provided by green spaces can help reduce urban heat island effect and risks of flood, improve resilience of ecosystems to preserve biodiversity and enhance human well-being through access to nature. Simultaneously, cities have to face another challenge: containing land take and urban expansion. The European Commission, in its Roadmap to a Resource Efficient Europe (2011), claimed the “aim to achieve no net land take by 2050”, a goal already transcribed in French law since 2021. Hence, the competition for land use which already existed between housing, industry, roads and recreational purposes will only become fiercer and have to include a new competitor: Nature-based Solutions. In this context, the ability of optimizing the implementation of such solutions – through the different scales at which they provide ecosystem services (building, neighbourhood, city and landscape) – is becoming primordial. Where should we conserve or restore green spaces in priority to ensure the providing of the ecosystem services needed for urban climate change adaptation? This question implies a multi-scale spatial analysis of the impact of green infrastructures on cities. To do so, the question of urban form is tackled by focusing on what is between buildings and streets, where green infrastructure can be deployed and woven into the urban fabric. To establish a multi-scale typology of green infrastructures based on their morphologies, classical approaches are combined with mathematical tools such as fractal analysis for characterizing their dispersion or graph theory for characterizing their connections, essential when studying biodiversity issues. This typology, associated with ecosystem services and biodiversity assessment for different French case studies (including the conurbations of Niort and Dijon), could help understand how to spatially implement Nature-based Solutions within cities, and be integrated into land-planning scenarios.

How to cite: Valide, L., Versini, P.-A., and Bonin, O.: Multi-scale analysis of green infrastructure morphology for climate change adaptation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1035, https://doi.org/10.5194/egusphere-egu24-1035, 2024.

As the global community grapples with the complex challenges of climate change, the integration of nature-based solutions (NBS) has emerged as a critical strategy. This work introduces a Web Geographic Information System (WebGIS) designed to showcase and communicate the results of initiatives focused on NBS within the scope of the Marine Coastal Ecosystems Biodiversity and Services in a Changing World (MaCoBioS) project. The platform serves as an interface for decision-makers and stakeholders, providing a spatially contextualized visualization of geospatial data related to marine and coastal ecosystems, climate risks, and adaptation. The MaCoBioS webGIS is based on an open-source platform, using JavaScript and the Leaflet map library to showcase key scenarios developed for case study ecoregions. The platform allows remote access to data irrespective of geographical constraints and is capable of integrating multidisciplinary data, ensuring a comprehensive and up-to-date view of evolving climate-related scenarios. The MaCoBioS webGIS not only facilitates the identification, evaluation, and direction of potential solutions to extant and emergent issues but also affords public access and participation. It serves as a foundational platform for prospective local and regional areas monitoring and management. By integrating qualitative information with scientific data, the aim is to present the results clearly and in a straightforward language, to reach a broader audience, including those who may not have specialized expertise. In so doing, it establishes the groundwork for future initiatives, promoting collaboration and leveraging cutting-edge technology for the betterment of coastal communities and ecosystems. In summary, the webGIS not only serves as a powerful tool for visualizing geospatial data but also acts as an effective means of communication and collaboration. By promoting informed decision-making, and supporting initiatives related to climate change and NBS, the platform contributes to the collective effort in addressing the complexities of our changing climate.

How to cite: Uchôa, J., Fonseca, C., Tiengo, R., Almeida, B., and Gil, A.: WebGIS for Marine Coastal Ecosystems: A Dynamic Interface for Communicating and Collaborating on Nature-Based Solutions in Climate Change Mitigation and Adaptation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2018, https://doi.org/10.5194/egusphere-egu24-2018, 2024.

The Great Green Wall (GGW) is a multibillion-dollar African initiative to combat desertification in the Sahel by restoring 100 million hectares of degraded land. The idea of a physical green wall of trees has now been developed into the implementation of scattered green zones throughout arid areas, providing sustainable reforestation, revegetation, and land management. In West Africa, the most important climate feature is the West African Monsoon (WAM), which brings rainfall over the Sahel during the Northern Hemisphere summer. Climate dynamics associated with WAM changes could also play a role on the Atlantic Tropical Cyclones (ATCs) formation and variability. The potential climate impacts of the most recent GGW plan on northern Africa and tropical Atlantic have not yet been adequately evaluated, raising concerns about unforeseen climate ramifications that could affect stability in northern Africa and impact on the ATC variability. Here, we use a high-resolution (~13 km) regional climate model to evaluate the climate impacts of four GGW scenarios with varying vegetation densities under two extreme emission pathways (low and high). Higher vegetation density GGW scenarios under both emission pathways show enhanced rainfall, reduced drought lengths and decreased summer temperatures beyond the GGW region relative to the cases with no GGW. However, all GGW scenarios show more extreme hot days and heat indices in the pre-monsoonal season. Furthermore, in spite of a strong variation in the African Easterly Waves activity, no significant changes are found in terms of ATCs frequency, intensity, meridional motion and translation speed over the North Atlantic area. Small changes in the TC densities are found in front of the cost of West Africa,  in the eastern side of the Main Development Region. These findings highlight the GGW's contrasting climatic effects, emphasizing the need for comprehensive assessments in shaping future policies.

How to cite: Ingrosso, R. and Pausata, F. S.: On the climate impacts of four different Great Green Wall scenarios on the northern Africa and the Atlantic Tropical Cyclones variability., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2883, https://doi.org/10.5194/egusphere-egu24-2883, 2024.

Given the local pollution near the school in Follonica(Gr)-Italy, specifically at the Gora river’s mouth, students have designed a study (IBSE method) of the chemical and ecological indicators of the river's situation. Analyzing the city's history about climate, the changes of the water regime and the shape of the river during the XX century, they have measured the indicators (physical and chemical parameters of the water, Extended Biotic Index). Creating a website and an interactive map of the river, they have communicated the situation to the local authorities, so the school has become involved in the "Pecora River Agreement", a local project aiming to the redevelopment of the river ecosystem. Students make proposal: plants in the riverbank, activities to sensitize local community and monitoring through ecological index for the future of the city.

How to cite: severi, A.: Requalify our river: from a school project to a city project, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3616, https://doi.org/10.5194/egusphere-egu24-3616, 2024.

The recently released IPCC Mitigation report placed agroforestry as one of the top three Agriculture, Forestry and Other Land Use (AFOLU) mitigation pathways, noting that it delivers multiple biophysical and socioeconomic co-benefits such as increased land productivity, diversified livelihoods, reduced soil erosion, improved water quality, and more hospitable regional climates, concluding there is ‘high confidence’ in agroforestry’s mitigation potential at field scale. As such, agroforestry is one of the most cited nature-based solutions in development strategies and in reporting of nationally determined contributions (NDC),  both for its potential mitigation benefits, but not least for the adaptation, resilience and livelihood benefits it can provide, across scales from agro-industrial farming to small farmer holdings. Here we present recent global and regional estimates of above- and below-ground biomass on agricultural land based upon IPCC Tier 1 estimates and compare results with an updated carbon density map based on remote sensing, with results indicating the methodology and initial estimations are robust. Two future scenarios are evaluated to estimate carbon sequestration potential of increasing tree cover on agricultural land: 1.) incremental change and 2.) systematic change to agroforestry. Estimates of above- and below ground biomass carbon were combined with a remote sensing-based tree cover analysis to estimate the increase in biomass. Global increases (4-6 Pg C for incremental change; 12-19 Pg C for systematic change) highlight substantial mitigation potential. Increasing global tree cover on agricultural land by 10% would sequester more than 18 Pg C over a decade. South America has the highest potential, followed by Southeast Asia, West and Central Africa, and North America. Brazil, Indonesia, Philippines, India, the United States and China are among the top countries. Additionally, we provide an overview and analysis of the unique and significant contribution agroforestry can provide in mountainous regions and in reducing pressure on irrecoverable carbon.

How to cite: Zomer, R., Xu, J., Spano, D., and Trabucco, A.: Nature-Based Solutions: Evaluating the global carbon sequestration potential of agroforestry and increased tree cover on agricultural land., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6018, https://doi.org/10.5194/egusphere-egu24-6018, 2024.

To mitigate climate change impacts in cities, nature-based solutions are broadly promoted due to their supposed benefits for biodiversity, rainwater management, evaporative cooling, and sequestration of carbon. Among existing solutions, green roofs show the advantage of tackling the lack of space available for greening in urban areas. But green roofs are still underdeveloped due to their cost and the lack of scientific knowledge around their potential, especially for carbon sequestration. Quantifying the various contributions of green roofs using reliable scientific approaches is a major challenge. Thus, it is essential to build a numerical model capable of simulating green roofs development and functioning at city scale in order to provide information to decision-makers with relevant indicators.

Here, the urban canopy model Town Energy Balance (TEB) with the module TEB-GREENROOF is used to model green roofs. The TEB-GREENROOF model, evaluated in previous study for heat and water transfers, is improved by activating the photosynthesis model ISBA-A-gs in order to represent the CO₂ exchanges of the vegetation implemented on the green roof. The modelling is informed by 6 years of continuous CO₂ flux data on a non-irrigated extensive green roof located in Berlin (Germany) in partnership with the Technische Universität Braunschweig. In order to evaluate and improve the thermal, hydrological and respiration characteristics of the ISBA-A-gs model on a green roof, an initial simulation is carried out by forcing the monthly evolution of the leaf area index (LAI) by LAI data estimated experimentally. The model is then applied with a dynamic calculation of LAI in order to enable it for simulations of roof greening scenarios on a city-wide scale under any climate with no information on the LAI.

Results show that the model is able to estimate the annual net ecosystem exchange of the Berlin green roof and to correctly reproduce the CO₂ fluxes for both diurnal cycles and annual variation under climate variability, with drier years showing less carbon sequestration.

How to cite: Mirebeau, A., de Munck, C., Weber, S., Lemonsu, A., and Masson, V.: Modelling CO2 flows from extensive green roofs within the TEB (town energy balance) urban canopy model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6169, https://doi.org/10.5194/egusphere-egu24-6169, 2024.

How to cite: Vanacker, V., Molina, A., Rosas, M., Bonnesoeur, V., Román-Dañobeytia, F., Ochoa-Tocachi, B., and Buytaert, W.: Nature-based solutions for erosion mitigation : insights from a systematic review for the Andean region, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6608, https://doi.org/10.5194/egusphere-egu24-6608, 2024.

To tackle hydrometeorological extreme events and adapt to climate change, Nature-based Solutions (NbS) are widely considered a promising approach. Yet, their implementation remains challenging. One key reason is that NbS require a lot more land than grey infrastructure – making their implementation dependent on privately owned land and prone to cause or exacerbate conflicts of interest over land use. This request of privately owned land widens the numbers of actors involved in the decision-making process. For this very reason, the realisation of NbS highlights the necessity of meaningful stakeholder engagement. However, in the past, technical mitigation measures were traditionally enforced top down by engineers within the public administration at national or regional level. Stakeholder engagement thus fundamentally changes the way how risk managers and citizens collaborate and is often reported to not live up to its expectations. Therefore, this study will address the role of stakeholder engagement as a decisive factor for the implementation of NbS on privately owned land. More specifically, it aims (i) to analyse what approaches to stakeholder engagement are currently employed on the side of flood risk authorities and (ii) to evaluate how stakeholder engagement processes account for conflicts of interest over land use. For this purpose, a qualitative research design approach will be exerted. This will involve desk research to identify areas in Austria where NbS on privately owned land have already been (and will be) implemented, semi-structured interviews with public water authorities and workshops in our case study site – the Lafnitz catchment in Austria. Lessons learnt will be compared with those of five other regions across Europe, as our study is embedded in the EU Horizon Project “Land4Climate” (Utilization of private land for mainstreaming Nature-based Solutions in the systemic transformation towards a climate-resilient Europe, HORIZON-MISS-2022-CLIMA-01-06). By doing so, our research will provide hands-on knowledge on NbS implementation and foster its mainstreaming across the European Union.

How to cite: Wallner, M., Thaler, T., Schindelegger, A., and Gugerell, K.: Nature-based Solutions on privately owned land: Stakeholder engagement matters, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7898, https://doi.org/10.5194/egusphere-egu24-7898, 2024.

Idea and Objectives: The health and well-being of urban populations are increasingly under pressure from climate change, for example, due to temperature extremes resulting in heat stress. The demand for heat mitigation is particularly high for urban areas in humid, tropical climates, as they are affected by heat stress already today, and for which a further amplification of heat stress is expected. For the case of Hue, a humid tropical Central-Vietnamese city, based on a typology of selected green-blue infrastructure elements, potential benefits for the regulation of outdoor temperature and outdoor thermal comfort are systematically virtually implemented and modelled. In order to promote acceptance of greening interventions by the public in Hue, citizen demands and preferences towards urban green elements, including potential co-benefits, are considered in this study, and in so-doing, best practices for local action shall be identified.

Background: Vietnam is a country that faces multiple challenges. Climate change is anticipated to exacerbate natural hazard risks, i.e., of flooding, storms, and prolonged periods of extreme heat, which are known to increase the risk of mortality, particularly among vulnerable groups. This is compounded by ongoing, rapid urban growth, that urgently necessitates safeguarding urban ecosystem services to facilitate climate change adaptation, and to support human health and well-being. Elements of the urban green-blue infrastructure are typically regarded as efficient nature-based interventions for the delivery of often multiple ecosystem services, including benefits for urban heat mitigation, i.e., the improvement of outdoor thermal comfort. Accordingly, such measures are increasingly being funded, politically recognised and implemented in Southeast Asian countries, including Vietnam. However, specifically for Vietnam, certain knowledge gaps remain with respect to the effectiveness of greening interventions for heat mitigation under local conditions, as well as in regard to ensuring the implementation of locally relevant and thus sustainable and resilient nature-based solutions.

How to cite: Sumfleth, L., Scheuer, S., Nguyen, L., and Haase, D.: Urban green-blue infrastructure as nature-based solutions for urban heat adaptation in Hue city, Central Vietnam – Potential impacts in contrast to citizen demands for urban greenery, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7963, https://doi.org/10.5194/egusphere-egu24-7963, 2024.

Afforestation has long been discussed as a nature-based climate mitigation solution. Although it could be an economic, green, and safe climate mitigation method, several studies suggest the possibility of unforeseen consequences depending on how it is implemented. An important aspect to be taken into account when designing af- and reforestation plans is the risk of damage to the new forest system in the face of climate warming. Recent studies have already shown an increase in both wind and fire damage risks in northern latitudinal forests related to climate warming, with strong winds leading to breakage of individual branches as well as in the knock-over of individual trees or even entire forest areas.

However, the forest system is complex, with a high number of feedback loops between different types of damage and between forest structure and ecological parameters. A few examples: Trees that are weakened by damage from pest outbreaks and snowfall are more susceptible to damage from wind and fire; Gaps in the forest that are created by management or damage both increase wind flow due to an eddy effect and create new forest edges with poorly adapted trees, increasing the risk of wind-throw.

Due to this complexity, the resilience to damage and therefore ability of forests to mitigate climate on a regional scale are still poorly understood. Understanding this complexity requires model work and extensive literature research, as most studies only focus on a few aspects of the forest system, such as the management type or wind effects. The aim of the study is therefore to develop adequate and future-proof wind- and fire risk indices that boreal forest managers can use to improve management strategies to make climate-mitigation forests more effective, resilient and damage resistant.

To do this, output from the Weather Research and Forecasting (WRF) model is used in combination with data on damage, forest management and forest structure to shed some light on possible feedbacks between forest systems and climate on a small-scale basis, in this case 3kmx3km. This information is then used to expand the Canadian Forest Fire Weather Index (FWI) to include ecological, management-related and forest structural parameters. As the structure of the existing FWI is climate-based, the wind risk index will be based on the developed fire risk index.

Our preliminary results show that wind damage was most common and extensive in the south-western coastal area of Norway over the last two decades. In contrast, fire damage was most prevalent in the south, with increased damage extent in the south-west of the country. Furthermore, the FWI shows that under an afforestation scenario in Norway, the mountainous region will have the highest frequency of days with medium to high danger of forest fires under climate warming. In this presentation we will discuss these preliminary results, as well as the methodology we will be using to develop the risk indices. Policymakers and forest owners alike will be able to use the risk indices to make the climate-mitigation forests more resilient against damage in a warming climate.

How to cite: Ribbers, E., Lee, H., Mooney, P., Muri, H., Cai, L., Kim, J.-S., and Nieradzik, L.: Development of wind and fire risk indices for climate-mitigation forestry, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8691, https://doi.org/10.5194/egusphere-egu24-8691, 2024.

The proliferation of climate-induced stressors has deterred countries' green spaces (GS), which in turn degrade and deplete natural green barriers. Hence, Urban Green Infrastructure (UGI) modelling is grabbing global attention perceiving it as a nature-based mitigation/adaptation strategy to enhance the resilience of urban areas to fight climatic risks. UGI protects and improves the socio-ecological wellness of urban and rural regions. This research intends to investigate thirteen sustainable UGI indicators and their functional linkage with the five vital taxonomies of nature-based green solutions (at the neighborhood level) under a community participatory (CP) approach; out of ten GS elements and twenty-two sustainable UGI indicators developed by the author in his earlier research study [2-5]. It is to develop a sustainable UGI indicator-based framework (tailored to the native-built context) for climate-resilient urbanisation.

The results of the in-depth household survey (192 questionnaires), executed in three KP districts, Charsadda, Peshawar, and Mardan, and results were generated through Relative Importance Index (RII) and Interquartile Range Technique (IQR) show a very good level of coefficient alpha (α) value, (α = 0.7) — an acceptable threshold level [6, 7]. Furthermore, this study acknowledges key GS taxonomies that have achieved RII value ≥ 0.72. This performs a pivotal role in quality improvement and strengthening the resilience (health) of the respective UGI indicators. This scientific research study provides a foundation for an eco-regional paradigm in KP territory that paves the way for an effective implementation of green urbanism to naturally ameliorate the vulnerability to potential climatic stresses (like flooding, drought, the UHI effect) and disastrous impacts on the socio-ecological wellness.

Keywords: sustainable green infrastructure (GI) indicators; participatory planning (PP); nature-based green initiatives; climate change (CC); socio-ecological wellness; KP, Pakistan

References

1. Mell, I. C., Henneberry, J., Hehl-Lange, S., & Keskin, B. (2013). Promoting urban greening: Valuing the development of green infrastructure investments in the urban core of Manchester, UK. Urban Forestry & Urban Greening, 12(3), 296–306. http://dx.doi.org/10.1016/j.ufug.2013.04.006

2. Rayan, M., Gruehn, D., Khayyam, U., (2021b). Green infrastructure planning. A strategy to safeguard urban settlements in Pakistan. In: Jafari, M., Gruehn, D., Sinemillioglu, H., Kaiser, M. (Eds.), Planning in Germany and Iran. Responding Challenges of Climate Change through Intercultural Dialogue. Mensch und Buch Verlag. Berlin, pp. 197–220.

3. Rayan, M., Gruehn, D., & Khayyam, U. (2021a). Green infrastructure indicators to plan resilient urban settlements in Pakistan: Local stakeholder’s perspective. Urban Climate, 38, 100899. https://doi.org/https://doi.org/10.1016/j.uclim.2021.100899

4. Rayan, M.; Gruehn, D.; Khayyam, U (2022a). Frameworks for Urban Green Infrastructure (UGI) Indicators: Expert and Community Outlook toward Green Climate-Resilient Cities in Pakistan. Sustainability 2022,14, 7966. https://doi.org/10.3390/su14137966.

5. Rayan, M.; Gruehn, D.; Khayyam, U (2022b). Planning for Sustainable Green Urbanism: An Empirical Bottom-Up (Community-Led) Perspective on Green Infrastructure (GI) Indicators in Khyber Pakhtunkhwa (KP), Pakistan. Int. J. Environ. Res. Public Health 2022, 19, 11844. https://doi.org/10.3390/ijerph191911844

6. Cortina, J. M. What is coefficient alpha? An examination of theory and applications. J. Appl. Psychol (1993).

7. Peterson, R. A. A Meta-analysis of Cronbach’s Coefficient Alpha. J. Consum. Res (1994).

8. Wu, J., & Wu, T. (2012). Sustainability indicators and indices: an overview. Handbook of Sustainability Management, 65–86. http://dx.doi.org/10.1142/9789814354820_0004

How to cite: Rayan, M., Gruehn, D., and Khayyam, U.: Community-driven sustainable green infrastructure (GI) indicators to plan an eco-friendlier and climate-resilient city-state in Khyber Pakhtunkhwa (KP), Pakistan., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8806, https://doi.org/10.5194/egusphere-egu24-8806, 2024.

Coastal zone ecosystems’ global importance is the primary driver of the wide scientific efforts for their restoration and protection. Over the past three decades, there has been a growing global momentum in the pursuit of initiatives aimed at conserving nature. Regardless of the wide scientific interest, and despite the notable exposure of these ecosystems to degradation and deterioration, numerous habitats, and species, in Europe, have 'vulnerable', or 'near threatened' conservation status. Even in the most favourable circumstances, factors including strong human pressure, urbanization and agriculture, and climate change, exhilarate the current, already, negative trends indicators, related to biodiversity and their associated ecosystem functions and services provision. This project proposes a set of existing and emerging methodologies and solutions for the restoration, conservation, and management practices, which are crucial to improving these profoundly delicate ecosystems in the Mediterranean and similar environmental contexts.

Traditional and innovative ecological restoration solutions have been designed and applied in two such areas along the Greek and Italian coasts, ‘Nestos Delta’ and ‘Bosco di Palo Laziale’, respectively, to improve the conservation status of 'Pannonian-Balkanic turkey oak-sessile oak forests' (habitat 91M0), ‘Alluvial forests with Alnus glutinosa and Fraxinus excelsior’ (habitat 91E0), and 'Mediterranean temporary ponds' (*3170) that have been increasingly exposed to climate change and inappropriate forest and water management.

Analogous, ecological restoration practices include selective trimming of encroaching shrub vegetation (and alien invasive shrubs in the Nestos area), remote-controlled irrigation system, origin-controlled and pathogen-free forestry nursery, ex-situ micro-propagation and in-situ reinforcement of keystone plant populations. An in-depth assessment and quantification of abiotic and biotic factors of the sites' ecosystems were preliminarily conducted to tailor these interventions to the habitats' geo-morphological, climatic, pedological, and physiological conditions.

The EU project LIFE PRIMED (LIFE17 NAT/GR/000511), operates at the Delta of River Nestos in Greece, and the Forest of Palo Laziale in Italy. The results in both areas, thus far, have demonstrated that the collaborative development of innovative water harvesting systems, coupled with adaptation measures, has the potential to enhance water resilience in already degraded forest ecosystems. To date, the project has successfully tackled the effects of escalating irregular rainfall patterns on Mediterranean coastal habitats by implementing a hydraulic system and a wellpoint-based water distribution network in Palo Laziale and Nestos Delta, respectively.

Monospecific approaches for climate and human-related phenomena, such as extreme weather events and agriculture pressure, are disfavoured. Therefore, the LIFE PRIMED project, comprised of an interdisciplinary team of Botanists, Zoologists, Foresters, and Environmental Engineers, has developed and delivered Nature-based transnational, ecosystem-oriented holistic solutions that will have the potential to be replicable and transferable with the greatest aim to recover dysfunctional, poorly managed coastal forest areas, across the Mediterranean region.

How to cite: Makaronidou, M., Emanuele Cambria, V., Korakaki, E., Georgiadis, C., and Petrou, N.: Opportunities to Restore and Protect Coastal Ecosystems with Enhanced Interdisciplinary Management - The Mediterranean Model., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9173, https://doi.org/10.5194/egusphere-egu24-9173, 2024.

Nature-based solutions are now a key part in climate change adaptation, particularly for urban environments. The integration of natural systems within the urban fabric has the potential to increase cities’ resilience to the predicted changes in climate. Urban forests are one of the most used methods for adding ecosystem services to an urban environment and at the same time address urban-specific climate change challenges such as heat-island effect, intense rainfall and water management. However, the effects of climate change in the long-term on urban forests are not often taken into account when planning interventions such as afforestation. Species selection for urban forests should, among other factors, be based on an assessment of local future climatic conditions, so to ensure the long-term viability of the project. Here we propose a methodology easily applicable to any place in Europe. We use data from interpolated publicly available climate datasets and species distribution data from the European Tree Atlas in order to analyse climatic niches for tree species in Italy. These climatic ranges are then compared to local climatic data, obtained from homogenised time-series measured by a weather station in the city of L’Aquila. The results are summarised in a suitability matrix providing vulnerability scores for each species based on predicted climate changes for the local area. The analysis ranks the species which are less vulnerable to projected future climate conditions. The application to the pilot area of L’Aquila suggests that some species already present will still be suitable also in future climate (e.g. Quercus pubescens) while others will not (e.g. Quercus petraea), and species not traditionally present may become suitable (e.g. Quercus ilex). The importance of obtaining accurate local climate data from observations is a key aspect for municipalities to consider as results of this analysis are greatly dependent on this.

How to cite: Gala, C., Curci, G., Pace, L., Marucci, A., and Del Tosto, D.: Assessing the vulnerability to climate change of tree species for urban afforestation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11439, https://doi.org/10.5194/egusphere-egu24-11439, 2024.

In fire-adapted forests around the world, nature-based solutions (NbS) are increasingly used as a tool to promote resilience to catastrophic fire through actions like fuels reduction and prescribed burning. This work also has many potential co-benefits, including climate change mitigation through stable carbon storage and biodiversity through habitat protection. One key mechanism for realizing both of these co-benefits is the protection of large and ancient trees, keystone components that sequester a disproportionate amount of carbon and serve as unique habitat for old forest associated species, many of which are declining or at risk of extinction. However, climate change poses a substantial risk to both tree recruitment and survival, either directly (temperature and drought tolerance) or indirectly (wildfire and insect occurrence). These impacts are not fully understood in the scientific literature nor, as a result, fully accounted for in the design of NbS management projects.

Therefore, to help inform near-term NbS restoration priorities, we investigated how a changing climate will impact the retention of large trees on the landscape and the ecosystem functions they support. Focusing on the Sierra Nevada, California, USA, a biophysically diverse and at-risk mountain ecoregion, we evaluated the intersection of current and future climate with large tree occurrence and two critical functions: carbon storage and habitat for the California spotted owl (Strix occidentalis occidentalis; CSO), an old growth associated species whose core population is limited to the Sierra Nevada and that requires large trees for nesting habitat. We mapped large trees across the Sierra Nevada, evaluated the climatic drivers of large tree biogeography, and forecasted how conditions supportive of large tree populations might shift geographically in the future under two emission levels (RCP 4.5 and 8.5). Using a bivariate fuzzy logic approach, we mapped the joint probability of current CSO occupancy and carbon storage and then evaluated future climate vulnerabilities and associated management strategies. We found that carbon and CSO occupancy corresponded closely with the current distribution of large trees in the Sierra, primarily at mid-elevations in the central Sierra. Similarly, we found that these mid-elevation montane forests are likely to continue to support large trees and CSO habitat and carbon storage through mid-century (e.g., consistent with "monitor" and "protect" climate-informed management strategies). Conversely, climate conditions in the southern Sierra and the upper elevations of the central Sierra are likely to constrain the persistence and recruitment of large trees, affecting the potential to recruit CSO habitat and enhance the carbon storage of higher elevation forests. 

We hope these findings will encourage the design of and investment in climate-informed NbS projects, and we propose that this method could be used in other ecosystems to jointly assess the climate change mitigation and biodiversity impacts of NbS-based management.

How to cite: Maurer, T., Manley, P., Anderson, C., Povak, N., Saksa, P., Kramer, A., and Peery, Z.: Leveraging the co-benefits of large tree protection to inform nature-based management of a forest ecosystem, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13018, https://doi.org/10.5194/egusphere-egu24-13018, 2024.

Modern cities are highly vulnerable to the adverse effects of climate change, primarily due to the escalating frequency of extreme weather events, including heatwaves. The current state of knowledge leaves no doubt that these effects are exacerbated by ongoing urbanization, leading to the continuous sealing of surfaces and a decrease in green areas in urbanized regions, contributing to the formation of Urban Heat Islands (UHI). These phenomena result in urban space degradation, causing economic, environmental, and demographic losses. Consequently, implementing solutions to enhance cities' resilience to climate threats should be a priority for local governments. Crucial in this context is the development of blue-green infrastructure, with a specific emphasis on micro-retention and the improvement of biologically active surfaces and vegetation habitat conditions. The implementation of such solutions, especially in the face of increasing extreme weather events, is essential for ensuring the sustainable development of smart cities.

This paper will present the results of research on the spatiotemporal distribution of the effectiveness of various components of blue-green infrastructure on a city-wide scale (including: river valleys, forests, urban parks, squares, pocket parks, and larger water bodies) in mitigating the UHI phenomenon in Wrocław, Poland. The study assesses the potential of blue-green infrastructure to mitigate the impact of heatwaves on the population most vulnerable to such threats. As an indicator of urbanized areas' vulnerability to the negative health effects of UHI, we focused on the population aged over 65. The research aims to provide crucial insights into how blue-green infrastructure can be optimized to effectively reduce UHI impacts and minimize health risks, especially within the most vulnerable age groups. This operation constitutes one of the initial stages in creating a prototype of a digital twin of the urban environment of Wrocław. The ultimate goal is to model information about blue-green infrastructure for the purpose of optimizing spatial policy in the context of adapting urbanized areas to climate change. This approach aligns with the Destination Earth initiative developed within the framework of the European Green Deal and EU Digital Strategy.

In the research, data integration was performed using various sources, including multispectral imagery from PlanetScope SuperDove, thermal data from ECOSTRESS LST, point clouds from airborne laser scanning (ALS), Topographic Objects Database (BDOT10k), and demographic data from municipal databases. Importantly, the utilized data are openly accessible and free of charge under the principles of Open Science, enabling the replication of procedures in other cities in Poland and, after identification and adjustment of relevant local data, numerous cities worldwide. In Wrocław, the project aims to provide support in creating and modifying existing and new planning documents, including local spatial development plans, the general plan, and the commune development strategy. This action supports the adaptation of local spatial policy to the growing needs of adaptation to climate change. The research is conducted within the program "Implementation Doctorate – 6th edition" by the Ministry of Education and Science.

How to cite: Budzik, G., Kowalczyk, T., Krajewski, P., Lebiedzińska, M., and Soszyńska, A.: Assessing spatiotemporal distribution of the effectiveness of Blue-Green Infrastructure in mitigating the Urban Heat Island phenomenon in Wroclaw, Poland under the Digital Twin concept for spatial policy optimization, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13070, https://doi.org/10.5194/egusphere-egu24-13070, 2024.

Wastewater management and treatment are key points in maintaining the quality and the sustainability of water resources. To preserve receiving  water environments, efforts are being conducted to improve the  treatment efficiency . Soil infiltration can therefore be used as a  nature-based solution tertiary treatment, in some areas without surface  water available, or with supplementary water bodies’ protection  regulations. Secondary wastewater effluents (SWE) infiltration surfaces mainly consist of infiltration trenches or flood-meadows. Among the main issues encountered with soil infiltration, two can be highlighted:  the possible low hydraulic conductivity induced by soil clogging, on the  one hand, and the use of non-renewable draining materials such as  pebbles or gravel to ensure the distribution of water in trenches, on  the other hand. In France, in order to overcome those issues,  stakeholders are now considering the replacement of the gravel with  woodchips, a renewable biodegradable material, also prone to  biodiversity in soils. It has been demonstrated through a previous field study that the use of woodchips in infiltration trenches helps maintain infiltration over time, and even improves their performance. However, understanding the underlying mechanisms remains a significant scientific challenge. To better understand the soil and woodchip evolution processes, four columns were set up in a laboratory and fed with secondary treated effluents from a wastewater treatment plant.

 These four columns (with a diameter of 37 cm) are composed as follows:

• a) Column #1: 80 cm of soil,
• b) Column #2: 40 cm of wood chips and 40 cm of soil,
• c) Column #3: 80 cm of soil inoculated with a selection of earthworms ,
• d) Column #4: 40 cm of wood chips and 40 cm of soil, inoculated with a selection of earthworms .

During the presentation, hydraulic monitoring of the columns will be presented (inlet and outlet flow, column weight monitoring), showing the evolution of the infiltration rate. To analyze the evolution of physical properties within the columns, including parameters like saturated hydraulic conductivity, a modeling study was carried out using Comsol Multiphysics. Specifically, the Richards model (van Genuchten-Mualem) was employed to simulate and understand the changes occurring over time. The models fit the data well. They mainly show that the soil columns (1 and 3) tend to clog early if the hydraulic loads are too excessive. This is reflected by a reduction of hydraulic conductivity at saturation and porosity. In comparison, columns with wood chips seem to maintain their properties, with no major difference between columns with or without earthworms, after two years of monitoring. These results will be compared to the monitoring of physicochemical parameters of the inflow and outflow waters from the columns, allowing for a better understanding of the processes involving woodchips, soil, and macrofauna.

How to cite: Louis, P., Lassabatère, L., Imig, A., and Clément, R.: NBS for secondary wastewater effluents infiltration based on soil and woodchips as drainage material: laboratory study   , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17239, https://doi.org/10.5194/egusphere-egu24-17239, 2024.

Over the last few decades, the urban hydrological cycle has undergone significant changes due to the influence of the built environment, resulting in rapid runoff and increased risk of flooding. Faced with these challenges, nature-based solutions (NBS) are emerging as an appropriate response, especially in densely populated areas, facing the impacts of climate change and biodiversity loss. The application of green infrastructures, as evidenced by Parc Molière in Les Mureaux, France, with its 700 trees, 11,500 m² of flowerbeds, 8,700 m² of grassland and 5,000 m² of gardens, represents a sustainable approach to urban stormwater management. By reintroducing extensive impermeable areas to the open air, Parc Molière strengthens biodiversity, facilitates animal movement, promotes air cooling and reduces urban heat islands, while also modifying hydrological behavior. Carried out in the framework of the LIFE ARTISAN project, this study uses the Multi-Hydro software, developed at the École des Ponts ParisTech, to computationally model the Parc Molière area in two different scenarios: before and after the creation of the green spaces. Based on a fully distributed and physical hydrological model, Multi-Hydro is able to illustrate the influence of NBS by comparing the obtained simulations with instrumented hydrological data. The results should demonstrate that the NBS have a significant impact on peak flow and total runoff volume, mitigating the negative effects in an urban hydrological scenario.

How to cite: Ávila Vasconcelos, I., Versini, P.-A., and da Silva Rocha Paz, I.: Nature-Based Solutions for stormwater management: A case study with Multi-Hydro in Parc Molière, France, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18619, https://doi.org/10.5194/egusphere-egu24-18619, 2024.

Nature-based solutions are an important tool to adapt to climate change in cities. Green spaces including nature reserves, parks and green streetscapes are essential to mitigate urban heat and also provide important recreation opportunities that benefit peoples physical and mental health. Effectively planning climate resilient and liveable cites thus requires quantitative, spatially explicit information about these ecosystem services. Such data are especially important in dense cities where vacant land is limited and trade-offs must be made to prioritise certain services. Here we present a multi-ecosystem service assessment for Singapore using the urban InVest models to evaluate urban cooling and urban nature access. We generate future greening scenarios based on policy targets to plant one million trees and increase the land area of parks by 50% by 2030 and compare ecosystem service provision for each scenario when either cooling or nature access is maximised in the spatial configuration of scenarios. We compare the benefits and trade-offs achieved by each scenario and explore the potential to quantify these through health indicators. Finally, we discuss how multi-ecosystem service assessment cans be integrated into urban planning and the implications for cities in an uncertain climate future.

How to cite: Ramsay, E., Tan, L., Wang, Y., and Hamel, P.: A multi-ecosystem service assessment for urban climate adaptation in Singapore , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18701, https://doi.org/10.5194/egusphere-egu24-18701, 2024.

The introduction of Natural Based Solution (NBS) into sustainable agricultural practices is a key issue on which the balancing of intensive agricultural activities with environmental protection depends. In lowland areas with intensive agricultural production, occurrences of extreme amounts of excess water, caused by climate change, increase the need for efficient drainage systems. Within the comprehensive framework of drainage system improvement, NBS are emerging as key and versatile interventions. The principal challenge lies in reconciling these solutions with the prevalent technical paradigms in both land reclamation and agriculture. The most important change is the strategic integration of the use of riparian buffers as supplementary melioration measures in delineated areas, especially aimed at reducing the inflow of excess water into the canal network. Deciding where to implement NBS for better drainage systems comes down to assessing the risks that may occur as a consequence to natural resources such as water and soil. When the implementation of NBS determines the crucial factors and evaluates them effectively, then it can categorize and map the optimal places where improvement of the drainage system is possible and efficient. In this study the aim was to delineate suitable zones for implementing nature-based solutions along watercourses through the application of Geographic Information System (GIS) methodology. By overlaying different layers, including pedological and geomorphological maps, digital terrain models indicating land slope, land use classifications, and drainage classes, it is intended to analyze and identify optimal locations. Some of the characteristic drainage systems in Vojvodina have been selected to provide a relevant case study illustrating how GIS can be applied to demonstrate the potential of nature-based solutions in improving drainage systems. This approach not only enhances the efficiency of the existing drainage systems. It also provides insights for strategic afforestation and the increase of biodiversity in agricultural areas.

How to cite: Vranešević, M., Knežević, M., Zemunac, R., and Meseldžija, M.: Suitability assessment of the location for the Natural Based Solution application on drainage systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18875, https://doi.org/10.5194/egusphere-egu24-18875, 2024.

The main concern with public policies and strategies for integrating nature-based solutions is to facilitate access to innovative interventions to reach cities and communities that are more sustainable and climate resilient. However, there is an impediment to linking information on the results of projects and the expected impact of the European Commission in the framework programmes for research funding. Here we show how projects targeting nature-based solutions help to implement and review public policies under the EU Strategy for Adaptation to Climate Change 2013 – 2020 and European Green Deal. These policies have a positive impact in various areas, especially in green transition, with the potential to analyse the link between the scientific results of nature-based projects and the strategic orientations of research and innovation. We focused on the evaluation of 150 projects funded at the Horizon 2020 and Horizon Europe level, within three main programmes that provide funding for projects based on nature, resilience and adaptation to climate change: (1) Climate action, Environment, Resource Efficiency  and Raw Materials, (2) Climate, Energy and Mobility and (3) Food, Bioeconomy, Natural Resources, Agriculture and Environment. The main analyzed elements are the number and type of partners, the level of funding, the main objectives of the projects, types of nature-based solutions and their distribution by geographical regions in Europe. This analysis leads to the filling in the existing knowledge of the results that produce science, so that it can be exploited throughout the community. Our results consist in (1) overview of climate challenges in EU R&I framework programmes Horizon 2020 and Horizon Europe, (2) Main NBS designed by European R&I organizations, (3) NBS for climate resilience implemented through EU R&I funding in Horizon 2020 and Horizon Europe, (4) NBS for climate resilience – key pathways of knowledge valorization for ecosystem restoration, preservation and management. Overall, they show that the aspects analyzed in the selected funded projects support the development of nature-based solutions and what are the main actions that lead to long-term impact.

How to cite: Barbu, G.-R. and Niță, M.-R.: Nature-based solutions for climate resilience in EU R&I framework programmes Horizon 2020 and Horizon Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19213, https://doi.org/10.5194/egusphere-egu24-19213, 2024.

Rural European landscapes are increasingly faced with the interlinked and cascading hazards of flooding and drought, exacerbated by both unsustainable land use practices and climate change. Sponge measures are particularly promising for addressing such multi-hazard risk from a participatory and social-ecological perspective. Sponge measures are nature-based solutions (NbS) that preserve, restore, enhance or create ecosystems to increase landscape and soil water retention while providing co-benefits for people and nature through biodiversity and ecosystem services. As NbS, they interact in complex ways with the socio-ecological systems (e.g. watershed boundaries) in which they are implemented. Thus, participatory processes are needed to ensure a systemic and interdisciplinary understanding of impacts while capturing diverse stakeholder values and interests. NbS design and planning often lacks 1) a shared understanding of the spatially-explicit impacts of NbS on the social-ecological system among stakeholders; 2) consideration of a broad spectrum of impacts as (co-)benefits and trade-offs; and 3) consideration of scales beyond the immediate measure and within diverging future scenarios.

As a promising approach to address these shortcomings, we propose the use of geodesign - an iterative framework for multidisciplinary, stakeholder-driven, and context-sensitive spatial decisions based on the integration of stakeholder inputs, geospatial data, and technology to generate real-time feedbacks and inform smart decision-making. This process also can support participation through fostering shared understandings and reconciling stakeholder conflicts. Despite promising applications in urban and landscape planning, knowledge is lacking on how and with what impacts geodesign can be applied to facilitate the planning of sponge measures at landscape scale. The aim of our research is to assess the utility of geodesign in the context of adaptive sponge measures by combining a systematic literature review with practical application of geodesign in two European catchments faced with increasing risk of hydrometeriological extremes. The review will quantify the adoption and past effectiveness of geodesign practices in similar landscape planning contexts. Based on these insights, a geodesign approach will be developed and implemented within the EU SpongeScapes project (spongescapes.eu) in selected case studies to generate future scenarios to increase landscape resilience against climate change. We present the research plan, including initial hypotheses and preliminary findings as conducted within the context of ongoing PhD research. With the increasing implementation of NbS in Europe in response to unfolding climate change and its consequences, our research will provide insights into the potential benefits and limitations of geodesign to improve their co-design, support policy creation, and inform decision-making.

How to cite: Jajeh, S., Anderson, C. C., and Albert, C.: Collaborative planning of nature-based solutions for climate resilience at landscape scale: exploring the potential of geodesign, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19504, https://doi.org/10.5194/egusphere-egu24-19504, 2024.

Nature-Based Solutions as a tool to reduce coastal risks have gained in popularity in the last 10 years. However, in France, their development still faces some limits and oppositions from local populations and stakeholders. The main reasons for this are the lack of knowledge and feedback, and the fear of being less protected with against floods with Nature-Based Solutions than with sea walls. This work will present the example of Criel-sur-Mer, in the North of France, where a project of restoration of intertidal habitats to reduce coastal risks is currently discussed and capitalize on feedbacks from three finalized projects from the Netherlands and England.

This study is part of a PhD work on the mobilization of Nature-Based Solutions in coastal protection projects. This presentation is based: on field trips conducted between March and April in the Netherlands and England, on the sites of Hedwige & Prosperpolder (Netherlands, Belgian border), Freiston Shore and Abbotts Hall (England), and in September 2022 and March 2024 in Criel-Sur-Mer (France); on semi-structured interviews conducted with stakeholders on those sites; on semi-structured interviews conducted with 39 coastal engineers and environmentalists between June and August 2023 in Artelia, the engineering firm in charge of the project of intertidal habitats restoration in Criel-sur-Mer; and on observative participation to a public consultation workshop with local actors and stakeholders for the project of Criel-sur-Mer.

The cross-study of the three Dutch and English projects gives us useful examples of the effectiveness of Nature-Based Solutions used as a tool to reduce coastal risks, that can be reused to enrich the project of Criel-sur-Mer. As the two English projects have been finalized in 2002, they are a source of extensive feedback on the evolution of intertidal ecosystems with managed realignment and their efficiency facing storms. The Dutch example started in 2005, but was finalized only in 2023, as it faced numerous social and political oppositions. These projects can thus be used as feedback on governance, project structuration and finding the right balance between different interests for the Criel-sur-Mer example.

How to cite: d'Avdeew, M.: Nature-Based Solutions for coastal risks protection: lessons learned from Dutch and English examples, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20731, https://doi.org/10.5194/egusphere-egu24-20731, 2024.

Cities and urbanizing spaces combine heat stress from both heat island effect due to the built environment as well as global warming.  India with its high rate of urbanization is no exception. However, many Indian cities have blue and green spaces with various levels of protection from land-use and land-cover change. 

Blue and green spaces (BGS) are potentially nature-based solutions for mitigating heat stress through evaporation and transpiration besides sequestering carbon and as a habitat for urban biodiversity.  The effectiveness of BGS in mitigating heat stress depends on size, shape, weather, and climate variables, especially humidity.  

We use satellite derived land surface temperature (LST) to quantify and map negative temperature anomalies (cooling) with respect to spatial average across the city in years with different levels of summer temperature, especially due to El Nino.   We analyse the diverse types of blue and green spaces in three metropolitan cities in India and classify them in terms of biodiversity value (using e-bird data and other published sources). 

Cooling more than few degrees Celsius with respect to city wide averages from blue and green infrastructure has been observed and is much higher if compared to nearby built areas.  The geometry and landscape ecology of existing urban blue and green infrastructure can help inform future planning for blue and green spaces as adaptation in a warming urban environment. 

How to cite: Krishnaswamy, J., Chandrasekharan, K., Mayavel, D., and Jambhekar, R.: Role of blue and green spaces in mitigating heat stress and providing biodiversity co-benefits in India’s cities , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20974, https://doi.org/10.5194/egusphere-egu24-20974, 2024.

Humans have been suffering increasingly from the escalating impacts of climate and ocean change.  Well known examples are droughts, flooding, wildfires, acidification, heatwaves, sea-level rise, extreme storms and biodiversity loss.  If global average temperature rises by more than 1.5°C above pre-industrial levels, multiple climate tipping points will be triggered, and indeed, some already are.  This is and will be devastating for people around the world, especially those in coastal areas.  Thus, the need for immediate and informed action has become urgent.

This presentation will outline some of the many concrete, local actions in the area of climate and ocean, undertaken by Méditerranée 2000 (Med2000), an environmental association in the South of France.  Since 1989, the association has committed its efforts and educational programs to promoting sustainable development.  Each year, the association educates more than 25,000 young people and adults, led by a team of ten specialized speakers.  Med2000’s initiatives include awareness campaigns about climate and ocean change, hands-on educational activities in local schools and events for the general public.

How to cite: Promduangsri, P., Promduangsri, P., and Bellanger, E.: Méditerranée 2000: Nurturing climate & ocean awareness, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-758, https://doi.org/10.5194/egusphere-egu24-758, 2024.

Academic researchers have long been advocates of various causes in the public arena; their public advocacy to take normative positions regarding various moral, political or social issues is not new. Today, however, in the face of the many challenges facing our society, the question of researchers' public positions, particularly in relation to the environment and climate change, is being raised anew. A number of climate scientists are committed in a variety of ways, from signing op-eds to participating in the work of NGOs or think tanks, supporting legal actions or writing blog posts. In addition, the development of traditional and social media has significantly increased the public exposure of these researchers. At the same time, serious questions are being raised within the research community. Many of its members are debating the ways in which researchers can engage in such public advocacy, its advisability, and even its very principle. However, these debates are currently taking place in informal settings and, given the extensive individual experience of a number of colleagues, it is probably time to engage in this discussion in a more collective and organised way, as is done in other research communities.

Here are some examples of questions that might be discussed. How can researchers engage in public advocacy safely and responsibly? What is the role of the scientist versus the expert versus the citizen versus the activist? Can a researcher be neutral when taking a public stance? What is the risk of appearing naive, manipulated or irrelevant? How should researchers deal with vested interests and private actors? Should the climate community research geoengineering? For whom should researchers develop climate services?

Because addressing these issues involves a tension between personal values that may go beyond those shared by the scientific community, they are essentially novel ethical questions. Some may be so intimidating that many researchers choose not to engage publicly. Care must therefore be taken to organise the exchange properly, for example by creating safe internal spaces for debate or by inviting experts from other disciplines.

The French CNRS Ethics Committee has recently published on opinions on these issues[1], which I will use as a starting point for a broader discussion.

How to cite: Guilyardi, E.: Freedom and Responsibility: the Ethics of Academic Researchers’ Public Advocacy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1344, https://doi.org/10.5194/egusphere-egu24-1344, 2024.

Cultural milieus determine the worldviews and practices of individuals and groups, including the reception of norms that guide them. Semiotic Cultural Psychological Theory (SCPT) methods, such as Symbolic Universes (SU), describe relationships of reception, worldviews and practice, which also applies to geo-philosophical matters [1]. This essay outlines how geoethics, for example, the Cape Town Geoethics (CTG), might be received in different cultural milieus.

The Cape Town Statement on Geoethics was proposed in 2016 at the 36th IGC [2] and is the most accessible resource on geoethics. It bundles various concepts in a Kantian/Aristotelian virtue ethics framework, illustrated, for example, by the Geoethical Promise [3].

The SU method describes the understanding, insights, and behaviour of groups of people expressing their respective cultural milieus. Extensive fieldwork identified five SU for people of European (Western) cultures [4]. The SUs called "Ordered Universe", "Interpersonal Bond", "Caring Society", "Niche of Belongingness", and "Others' World" categorise milieus, for example, in terms of relation to power and institutions or sources of trust. They corroborated with the Kohlberg hierarchy of the level of societal coordination [5] that is applicable to associate CTG and the worldviews of individuals and groups [6].

Comparing CTG and SU indicates: (1) CTG resonates most positively with people of the cultural milieu “Ordered Universe” (highest Kollberg level); (2) in other milieus, the reception of the CTG will be “measured”; (3) reception will be adverse for the milieu “Others' World” (lowest Kohlberg level). Hence, considering the quantitative distribution of SUs (in Europe), European citizens' reception of CTG is likely restrained.

Given complex-adaptive social-ecological systems of the World and Nature couple world views, human practices, and societal and natural systems [7] (see example: [8]), whether variants of CTG “fitted to different milieus” should be developed is of practical relevance. The perception of norms and their acceptance or rejection is a system feature, of which geoethics should not be agnostic.

[1] Bohle M (2019) “Homo Semioticus” Migrating Out of Area? In: Salvatore S, et al. (eds) Symbolic Universes in Time of (Post)Crisis. Springer Berlin Heidelberg, Cham, pp 295–307

[2] Di Capua G, et al. (2017) The Cape Town Statement on Geoethics. Ann Geophys 60:1–6. https://doi.org/10.4401/ag-7553

[3] Matteucci R, et al. (2014) The “Geoethical Promise”: A Proposal. Episodes 37:190–191. https://doi.org/10.18814/epiiugs/2014/v37i3/004

[4] Salvatore S, et al (2019) The Cultural Milieu and the Symbolic Universes of European Societies. In: Salvatore S, et al. (eds) Symbolic Universes in Time of (Post)crisis. Springer, Cham, pp 53–133

[5] Kohlberg L (1981) The Philosophy of Moral Development: Moral Stages and the Idea of Justice. Harber & Row, San Francisco

[6] Bohle M, Marone E (2022) Phronesis at the Human-Earth Nexus: Managed Retreat. Front Polit Sci 4:1–13. https://doi.org/10.3389/fpos.2022.819930

[7] Preiser R, Woermann M (2019) Complexity, philosophy and ethics. In: Galaz V (ed) Global Challenges, Governance, and Complexity. Edward Elgar Publishing., Cheltenham, pp 38–62

[8] Talukder B, et al. (2023) Complex Adaptive Systems-Based Conceptual Framework for Modeling the Health Impacts of Climate Change. J Clim Chang Heal 100292. https://doi.org/10.1016/j.joclim.2023.100292

How to cite: Bohle, M., Preiser, R., and Marone, E.: Perceiving Cape-Town-Geoethics (CTG) through Symbolic Universes (SU), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2053, https://doi.org/10.5194/egusphere-egu24-2053, 2024.

Learning about geoethics is not easy partly because the area is relatively new (having emerged in the early 2010s), the concepts are sometimes difficult to fathom and geoethics touches on such a wide area of geoscience phenomena and on such a variety of human issues.

Learning through active, participatory engagement has been developing since the 1960s, and is now deployed, albeit sporadically, across the full educational and training spectrum (from the humanities, through the social sciences to the hard sciences).  Methods that have developed in this learning paradigm include project work, internships, experiential learning, simulation/gaming, values clarification and many more.  We contend that participatory methods are an effective way in which to learn, as supported by much research.

Our poster invites you to participate in a game-like, values clarification exercise.  We have developed a new version of an exercise that we have used in several places (Austria, Costa Rica, France, online) to unravel the knotty relations among values, principles and behaviours related to geoethical issues and dilemmas.

It is possible to play alone, but it is more enlightening and engaging to play in pairs or small groups.  Please bring a friend or two to our poster and participate in our exercise.  The basic process of the exercise can be adapted to your own specific areas of interest.  We look forward to seeing you – please bring a pencil.

^{(This poster was originally intended as a workshop in a short course, but our SC proposal was declined.)}

How to cite: Crookall, D., Promduangsri, P., and Promduangsri, P.: Geoethics literacy:  Clarifying values, principles and behaviour, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2607, https://doi.org/10.5194/egusphere-egu24-2607, 2024.

Geosciences play an indispensable role in the functioning of contemporary societies. Nevertheless, the technological aspects associated with the practical application of geoscientific knowledge, should not overshadow the fundamental contribution of geosciences to shaping human thought. Geosciences have not only influenced but continue to shape our perception of the world, its interrelationships, and evolution.

The ongoing ecological crisis, with its environmental, social, cultural, economic, and geopolitical implications, has stemmed from an imprudent trajectory in human development. Regrettably, there have been instances where geosciences have contributed to this irresponsible path. This oversight has led to an undervaluation of the social and cultural significance inherent in geological disciplines and the crucial role they can play in addressing current global challenges to support human societies.

Geoethics, as the ethics of responsibility towards the Earth system, is grounded in the comprehensive understanding provided by geoscientific knowledge of the complexity of reality. It stands out as the optimal tool for cultivating a new perspective on geosciences, recognizing them as fundamental disciplines crucial for addressing global environmental challenges. This recognition extends beyond technical considerations, emphasizing their cultural significance. By virtue of their epistemological foundations, the geosciences collectively represent an invaluable reservoir of knowledge for human civilization. They are indispensable for redefining the intricate relationship that binds us, as humans, to the Earth.

For this reason, geoethical thought should serve as a complementary element to knowledge in the education of geoscientists. It aims to furnish them with a principled framework and ethical values, offering guidance for any application of geoscientific knowledge to the natural environment and human communities. Additionally, geoethical thought is the ground on which to set a shared, global ethical foundation, facilitating the advancement of our interactions with nature. It seeks to actualize an ecological humanism that forms the basis for human well-being and a more sustainable development of socio-ecological systems. The geoethical perspective redefines the cultural significance and objectives of the geosciences. Geoeducation and communication emerge as fundamental tools for bridging the gap between geosciences and society. They play a crucial role in promoting geoscientific knowledge, highlighting not only its scientific value in providing technical solutions to the ecological crisis but also emphasizing the philosophical dimension of geosciences, the geosophy of living consciously and responsibly within the Earth system.

How to cite: Peppoloni, S. and Di Capua, G.: Exploring the horizon of geosciences through the lens of geoethics, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3568, https://doi.org/10.5194/egusphere-egu24-3568, 2024.

The development of the theoretical foundations of geoethics and its practical applications have had a notable boost in recent years, seeing the involvement of a growing number of scholars from different disciplines. This has increasingly necessitated the creation of spaces where reflections, discussions, results, and study materials can be shared. The network of scholar relationships has progressively developed physical and conceptual spaces for discussions. The goal has been to sustain conceptual consistency in geoethical thinking by anchoring reflections in the discipline's historical evolution and fostering further developments through open analysis, welcoming contributions from diverse disciplinary backgrounds. Today, what can be defined as a research infrastructure on geoethics and the promotion of its contents possesses a complex structure, serving as a convergence point for various cultural and scientific experiences.

At the core of this infrastructure lies the International Association for Promoting Geoethics - IAPG (https://www.geoethics.org), established in 2012. It consists of an Executive Committee, national sections, and Task Groups focusing on specific topics within geoethics. More recently, two new entities have augmented this infrastructure: i) the Commission on Geoethics of the International Union of Geological Sciences (IUGS), established in February 2023, that is the supporting branch of the IAPG to the IUGS and the IUGS body that officially deals with geoethics and social geosciences for the Union; ii) the Chair on Geoethics of the International Council for Philosophy and Human Sciences (CIPSH, an organization operating under the umbrella of UNESCO), established in December 2023, with the aim of expanding and reinforcing an international research network of institutions, not-governmental organizations, and individual scholars to foster interdisciplinary initiatives for bridging geosciences, humanities, and social sciences through geoethics.

The research infrastructure on geoethics has been enriched over time with two editorial initiatives: a) SpringerBriefs in Geoethics series by Springer Nature (https://www.springer.com/series/16482), founded in 2020 and supported by the IAPG, that envisions a series of short publications that aim to discuss ethical, social, and cultural implications of geosciences knowledge, education, research, practice and communication; b) the Journal of Geoethics and Social Geosciences (https://www.journalofgeoethics.eu/), a diamond open access publication of the National Institute of Geophysics and Volcanology (Rome, Italy) and supported by the IAPG, founded in 2021.

Finally, the research infrastructure on geoethics is complemented by the School on Geoethics and Natural Issues (the “Schola”), founded in 2019 (https://www.geoethics.org/geoethics-school). The “Schola” is a place for teaching and learning of the principles and values of geoethics in the light of the philosophy and history of Earth sciences. The intent is to provide background knowledge and the evaluation skills necessary to understand the complex relationship between human action on ecosystems and the decisions geoscientists make in the discipline that impact society, including improving the awareness of professionals, students, decision-makers, media operators, and the public on an accountable and ecologically sustainable development.

How to cite: Di Capua, G. and Peppoloni, S.: An infrastructure for researching on geoethics and facilitating its international promotion, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3586, https://doi.org/10.5194/egusphere-egu24-3586, 2024.

The ocean has started to attract more attention in the recent past with the notions of Blue Economy and Blue Growth becoming rallying points for a new frontier for investments [1]. Many countries and institutions prepare policy papers promising to end poverty, a push for new technologies and profits to fund the development. A recent systematic review of the literature [2], however, found no trace of articulated ethics and justice notions in midst of all the lofty hope and hype surrounding the often blurred concepts. The increasing financialisation of technological developments accelerated through digitalisation and the internet are creating increasing injustices to humans and harm to nature. But, as Rushkoff argues [3], the possibilities for feedback and more circular reasoning have potential to teach everybody that there is no escape from the natural world, thus weaning us from the hyperbole of permanent exponential growth. Here it is argued that critically engaged ocean and geo-sciences with their inherent message of a changing planet through deep time can contribute to debunking the ahistorical promise of fixing self-created problems by starting on a presumed ‘clean slate’. We frequently observe a pattern of wanting to solve the damage provoked by one technology with more technology, e.g. deep sea mining [4] or further technology development in fisheries and aquaculture [5]. At country level, these deliberately disruptive industrial approaches often pay little attention to working with the affected small-scale wild food producers who account for a quarter of global production. Instead, harnessing a combination of traditional and indigenous knowledges and providing intelligible access to the sciences holds significant potential for less destructive pathways. That would also be consonant with the promotion of knowledge co-creation during the UN Ocean Decade in pursuit of a vision of ‘the science we need for the ocean we want’. Practice of co-creation will require some rethinking of the self-image of many sciences and adaptations to typical project formulation and flows. In return, this is expected to produce valuable new insights in addition to opportunities for cooperation and blue justice as steps towards transformations based on ethical principles.

[1] World Bank. (2016). Oceans 2030: Financing the blue economy for sustainable development. Blue Economy Development Framework, Growing the Blue Economy to Combat Poverty and Accelerate Prosperity. World Bank Group, Washington DC.

[2] Das, J. (2023). Blue Economy, Blue Growth, Social Equity and Small-scale Fisheries: A Global and National Level Review. Studies in Social Science Research, 4(1):45 p. DOI: https://doi.org/10.22158/sssr.v4n1p38

[3] Rushkoff, D. (2022). Survival of the richest. Escape fantasies of the tech billionaires. Scribepublications, UK, ISBN 978-1-915590-24-4, 212 p.

[4] Zenghui Liu, Kai Liu, Xuguang Chen, Zhengkuo Ma, Rui Lv, Changyun Wei, Ke Ma. (2023). Deep-sea rock mechanics and mining technology: State of the art and perspectives. International Journal of Mining Science and Technology, 33(9):1083-1115. https://doi.org/10.1016/j.ijmst.2023.07.007.

[5] FAO. (2022). The State of World Fisheries and Aquaculture 2022: Towards Blue Transformation. Rome, FAO. doi:10.4060/cc0461en

How to cite: Nauen, C. E.: Can geosciences help inserting social justice notions into Blue Economy narratives?, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4054, https://doi.org/10.5194/egusphere-egu24-4054, 2024.

Science indicates that human impact on the planet's climate is clear. Over the past 30 years, climate change has shifted from being primarily a scientific concern to emerging as one of the defining environmental challenges within our society. However, science alone cannot guide us on how to address this crisis. This challenge is also about how we envision living together, what we collectively value, and the level of risk we are prepared to assume. It fundamentally pertains to the kind of society we aspire to, making education a pivotal component. Inspired by the Paris Agreement, the time has arrived for Climate Change Education. It derives its momentum from the aspirations and mobilization of the youth, making it the most potent transformative action in response to climate change.

Climate Change Education comes with unique and exciting opportunities. Firstly, it offers a chance to learn about science in general and climate science specifically, drawing from authoritative sources like IPCC reports. Secondly, it provides an avenue to acquire life skills, humanities knowledge, and insights into global citizenship, imparting a holistic perspective to the young generation on a global scale. Lastly, it fosters critical thinking, hopeful hearts, and empathy in an ever-evolving educational landscape. However, Climate Change Education presents numerous challenges as it strives to balance the development of cognitive, emotional, and practical aspects within existing educational systems. Educators need to be prepared for this unique combination of ‘head’, ‘heart’, and ‘hands’.

The mission of the Office for Climate Education (OCE) is precisely to empower educators in preparing young generations with a robust understanding of climate change and the skills needed to act as global citizens in a changing world. The OCE, driven by collaboration between climate science and educational communities, develops sets of pedagogical resources, offers teacher professional development opportunities, and facilitates networks of practice worldwide. As a pivotal participant in the newly established Greening Education Partnership, the OCE serves as a bridge between the global landscape of IPCC-based science and the specific needs of local primary and secondary educational systems in over 20 countries.

How to cite: Guilyardi, E. and Wilgenbus, D.: Exciting times for Climate Change Education – from global opportunities to local challenges, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6101, https://doi.org/10.5194/egusphere-egu24-6101, 2024.

The National Association of State Boards of Geology (ASBOG) plays an essential role in supporting the licensing of applied geoscientists in more than 30 states in the United States [1] through promulgating model law, rules, and regulations for professional licensure, [2] by developing and implementing the Fundamentals of Geology (FG) and Practice of Geology (PG) exams, and [3] by providing related educational materials.  The content of the FG and PG exams is driven substantially by the results of Task Analysis Surveys (TAS) taken by practicing geologists and academic geologists.  Before 2023, the exams included content related to ethics reflected in the earlier TAS analytical summaries;  however, ethics content is not included in the 2023 TAS or, reportedly, in the current FG or PG exams.
     ASBOG has a history of including applied ethics in its products and organizational structure.  There is a "Code of Conduct/Harassment Policy and Performance Guidelines" for the ASBOG organization on its website (ASBOG.org).  The "Professional Geologist Model Licensure Law" states that each applicant must "submit a signed statement that the applicant has read and shall adhere to any code of professional conduct/ethics and rules established by the Board..." and that the application "be signed and sworn to by the applicant before a notary public" (ASBOG 2017, lines 844-847).  Its "Model Rules and Regulations" includes a sample "Code of Ethics" for licensed professional geologists (ASBOG 2019, p. 27-29).  
     Geoscience professional organizations in the US and internationally affirm the fundamental importance of ethics in academic and applied geoscience.  Virtually all professional organizations relevant to applied-geoscience practice in the United States (e.g., AAPG, AGI, AGU, AIPG, AEG, ASBOG, GSA, SIPES...) have some form of ethics code that their members are obligated to know and adhere to.  The International Association for the Promotion of Geoethics (IAPG -- www.geoethics.org) curates a list of codes of ethics/professional practice and provides publications and educational opportunities supporting geoethics.  Another essential resource is the "Teaching Geoethics" website (serc.carleton.edu/geoethics -- Mogk and Bruckner, 2014-23).
     Robert Tepel (1995) described the essential connection between licensure laws and professional ethics.  To the extent that there is a lack of ethics content in the current 2023 TAS, candidate handbook, exam preparation resources, and FG and PG exams, ASBOG sends a message that applied ethics might not be a core competency for licensed geoscientists -- a message for which there is essentially no support among geoscience professional organizations.
          I suggest that ASBOG collaborate with IAPG and other relevant organizations to address the problems or concerns that resulted in the reported elimination/reduction of ethics content in the application, preparation, and implementation of its FG and PG exams.  Licensed professional geoscientists must continue to understand that geoethics is foundational for their work within society.  For references and resources, visit CroninProjects.org/EGU-Geoethics2024/.

How to cite: Cronin, V.: The need to include ethics content in professional licensure exams in the US (and worldwide), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6136, https://doi.org/10.5194/egusphere-egu24-6136, 2024.

The proposal of the Geoethics Code (hereinafter “Code”) of the Geological Society of Chile arises as a strategic objective of the Geoethics Group within this institution. The Code encapsulates the principles and values that ethically guide and protect the professional decisions of geoscientists in Chile to protect society and the environment. Likewise, it establishes standards of conduct from the personal to the environmental dimension of professional and scientific practice. Consequently, the Code serves as a valuable tool to the geoscientist community in Chile, facilitating reflection and decision-making within an ethical framework.

Grounded in the principles and values defined by the Geoethics Group of the Geological Society of Chile and the Cape Town Geoethics Declaration of the International Association Promoting Geoethics (IAPG) from 2016 (Di Capua et al., 2017), the Code is built upon four titles: a) Professional and scientific work; b) Geosciences and its relationship with society; c) Geosciences and its relationship with the environment; and d) Contribution to new generations of scientists and professionals in Geosciences.

The construction strategy of the Code underscores the pivotal role of the Chilean geoscientist community. Thus, the Code proposal was enriched through consultations, including surveys, meetings, discussions, and seminars, engaging the Geoscientist Community of Chile to understand their perspectives on pertinent topics and challenges. Furthermore, consultations and reflections were conducted to validate the Code proposal before and during the XVI Chilean Geological Congress in 2023. Ultimately, the Code underwent validation with experts from the IAPG, including geoscientists representing Latin America. Consequently, the Code authentically represents the concerns and challenges of the national geoscientific community while also resonating with the international geoscientific community.

Financing

This project is sponsored by the Geological Society of Chile.

Acknowledgements

To the geoscientist community of Chile, the IAPG experts and other professionals who have participated in the process of construction and reflection on the titles of the proposed Geoethics Code.

References

Di Capua, G., Peppoloni, S., Bobrowsky, P.T., 2017. The Cape Town Statement on Geoethics. Annals of Geophysics, 60, Fast Track 7: Geoethics at the heart of all geoscience. doi: 10.4401/ag-7553.

Keywords

Geoethics Code, Principles and Values, IAPG, Geoscientist Community.

How to cite: Bobadilla, H., Pinto Lincoñir, L., Ramirez, P., González, T., Benado, J., Lay, N., Villaseñor, T., Valenzuela, M., Alam, M. A., and Pérez, A.: Proposal for a Geoethics Code for the Geoscientist Community of Chile, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6573, https://doi.org/10.5194/egusphere-egu24-6573, 2024.

Educational approaches around the world are shaped by diverse geographical factors, including topography, climate, distance, urbanization and societal characteristics.  As a consequence, the methods employed for climate change education (CCedu) are expected to vary according to these geographical factors.

The United Nations Educational, Scientific and Cultural Organization (UNESCO) emphasizes the crucial role of CCedu in fostering an understanding of and effective response to the impacts of the climate crisis.  The Intergovernmental Panel on Climate Change (IPCC) highlights the importance of a globally conscious population for effectively addressing and adapting to climate change challenges.

However, rather than exploring the concept of CCedu or its effectiveness, my research project will focus on identifying the influence of geographical factors on climate change education/literacy.  In the long run, this project could potentially contribute to improving the effectiveness of CCedu.  I invite participants to visit my poster to discuss, share ideas and collaborate on this research project.

How to cite: Promduangsri, P.: Invitation to a research project on geography and climate education, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6593, https://doi.org/10.5194/egusphere-egu24-6593, 2024.

Environmental (in)justice arising from Climate change and urbanization exhibit uneven distributions, specifically impacting disadvantaged communities. While studies in the USA highlight the elevated heat exposure faced by low-income and ethnic minority groups, similar insights are lacking for other countries. This knowledge gap impedes a comprehensive understanding of environmental (in)justice experienced by various socio-economic and ethnic groups and hampers the identification of inadequacy in urban planning policies.

This research seeks to bridge the gap between social and environmental sciences to address environmental (in)justice by establishing a link between extreme heat (at both regional and country level) and socio-economic disparities for Australia and New Zealand. Using remotely sensed satellite data for Land Surface temperature mapping for summer (night time) and Census data of countries, the analysis explores various socio-economic indicators—such as education levels, age demographics, and the proportion of foreign populations.

Australia and New Zealand serve as pertinent case studies due to their distinct socio-economic landscapes and Indigenous populations. By recognizing the unequal distribution of urban heat and its disproportionate impact on vulnerable communities, there emerges a critical mandate to prioritize equitable urban planning policies. This research underscores the urgency for policymakers and urban planners to prioritize environmental justice interventions and integrate strategies that aim to reduce race and class disparities concerning urban heat. The findings also serve as a template for similar analyses globally; fostering inclusive, equitable and resilient urban landscapes.

How to cite: Chawla, J. and Benz, S.: Examining Race and Class Disparities in Urban Heat in Australia and New Zealand: Towards Environmental Justice in Urban Planning, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6662, https://doi.org/10.5194/egusphere-egu24-6662, 2024.

Leaders across geographical and political boundaries are united behind a pledge to deliver a net zero carbon world by 2050.  Society’s conundrum is that mining is an essential part of that delivery, yet is an activity regarded by many as unpalatable. Projects that have fallen short on ecological, ethical, or social grounds, serve to confirm to many that mining is currently not an industry to be trusted, rather than being the industry that could and should be empowering significant societal development.

Examples of societal failure include the incidents around the 2012 miners’ strike at the Marikana platinum mine in South Africa which escalated into violence and loss of life.  Failure on ethical grounds was most recently highlighted by the settlement of corruption claims in the Democratic Republic of Congo (DRC) where international mining company staff bribed country officials to secure “improper business advantages.”  Ecological failures are all too common and most visible in the failure of tailings storage facilities such as the 2015 Mariana (Brazil), 2019 Brumadinho (Brazil), and 2022 Jagersfontein (South Africa) dam disasters.

The challenge for those who explore, extract, and process the raw materials so vital for the energy transition, is to do so whilst delivering on true Sustainability right from the start of any project.  Mining disasters are rarely a surprise.  The proactive management of both threats and opportunities is therefore key to the urgent delivery of materials to secure our net zero future in a responsible manner.  We must ensure that this delivery is achieved by projects with wholly net positive outcomes for the environment and people.

How to cite: Herrington, R. and Gordon, S.: Delivering Critical Raw Materials: Ecological, Ethical and Societal Issues, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7655, https://doi.org/10.5194/egusphere-egu24-7655, 2024.

The concepts of biodiversity and ecosystem services, focusing on the diversity of life and the services provided to humans by such diversity, in interaction with abiotic ecosystem components, are well established. Only recently, geosciences have started to challenge this rather biocentric view by highlighting that geodiversity – understood as the diversity of minerals, rocks, geological structures, soils, landforms, and hydrological conditions – provides substantial services to society and should be treated as equal partner to biodiversity. It was proposed to use the more general term natural services or, where geodiversity is much more relevant than biodiversity, geosystem services. Even though the term geosystem services is more and more employed in literature, it evolves only slowly into a commonly used concept with a clearly defined meaning. Interpretations range from all services associated with geodiversity which are independent of interactions with biotic nature, to the restriction to subsurface services. None or few of these concepts, however, include risks as negative services, or as costs of services, which is surprising as this would enable a more integrated vision on human-nature relationships. Only very recently, the potential of geosystem service maps to highlight both services and risks related to geomorphological processes was pointed out.

This work picks up landslides as a type of geomorphological process and landform, which is rather negatively connotated in society and associated with risks rather than with chances. We use landslides to develop a broader understanding of geosystem services, together with the common understanding of hazards and risks. We will (i) present a sound and integrated conceptual framework to consider landslides within the field of tension between risks and resources, and (ii) highlight a case study where landslides are used as cultural geosystem services for environmental education in the context of UNESCO Global Geoparks, which are considered important instruments for conserving and promoting geodiversity.

How to cite: Mergili, M., Bauer, C., Kellerer-Pirklbauer-Eulenstein, A., Petermann, J., Pfeffer, H., Robl, J., and Schröder, A.: Can landslides provide geosystem services?, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8075, https://doi.org/10.5194/egusphere-egu24-8075, 2024.

The project “Protects and Heats” aims to safeguard the environment, to reduce the carbon dioxide emissions and the risk of collapse of buildings affected by earthquakes.

This is a new way to heat and cool buildings and at the same time mitigate the seismic vibrations.

The logic of the project is to create a discontinuity (Moat) in the ground in front of the structures to be protected, similar to damping methods that are implemented to dampen the vibrations produced by mechanical machines and without compromising the stability of the buildings themselves.

The project involves the construction of a double row of aligned micro piles and the insertion of HDPE and steel pipes inside the vertical drilling holes.

Closed circuit geothermal probes will be positioned, inside some vertical holes, with a low enthalpy closed circuit geothermal system.

The method of the project is achieved by combining two types of technologies:

-   The first concerns the interposition, between the direction of the seismic waves and the buildings, of a damping barrier.

The vertical barrier starting from the topographic surface will be positioned outside the buildings, generally orthogonal to the direction of the seismic waves.

-  The second concerns the installation of geo-exchange pipes, in the holes.

How to cite: Tavecchio, W.: Protects and Heats, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10646, https://doi.org/10.5194/egusphere-egu24-10646, 2024.

A geological definition of the Anthropocene, shorthand for humanity’s cumulative disruption of the Earth-Human Ecosystem, looms as the planet-and-people focused UN approaches its Summit of the Future in New York City on 22-23 September 2024. The International Union of Geological Sciences (IUGS) “aims to promote development of the Earth sciences through the support of broad-based scientific studies relevant to the entire Earth system”. With the UN recently declaring that the planet is in peril and in need of a rescue plan, Anthropocene considerations with a geoethical lens are urgently needed.

Each potential new interval in the Geological Time Scale begins with a working group mandated by the International Stratigraphic Commission (ICS), in the case of the Anthropocene also by its Subcommission on Quaternary Stratigraphy (SQS). The Anthropocene Working Group (AWG) was formed in 2009. In 2010, its first chair Jan Zalasiewicz with co-authors Mark Williams, Will Steffen and Paul Crutzen recognized that “the Anthropocene represents a new phase in both humankind and of the Earth, when natural forces and human forces become intertwined, so that the future of one determines the fate of the other”. In 2015, the AWG’s second and current chair Colin Waters with ten co-authors posed the question "Can nuclear weapons fallout mark the beginning of the Anthropocene Epoch?" in the Bulletin of the Atomic Scientists. This was affirmed in 2019 and the AWG presented its recommendation to the SQS in early 2024. The remaining review and decision steps are the ICS and IUGS. Reflecting concerns of other geoscience scholars as well as of other professions and an anxious public, an opposing mindset advocates for an Anthropocene event that spans the cumulative and ongoing environmental impacts of Homo sapiens. It views Geological Time Scale protocols as unsuitable for archaeological and contemporary developments, regards unemotive references to humanity’s most abhorrent invention as distasteful, and visualizes the Anthropocene Event as valuably informing a new zeitgeist for our troubled world.

In 1950 astronomer Fred Hoyle anticipated that humanity’s first view of the Earth from space would revolutionize the course of history. Insofar as a ‘giant leap of mankind’ did not result from NASA’s Apollo 1969 lunar mission with its estimated 600 million viewers, the Anthropocene Event fuels an opportunity for geoscience to inform a realistic outlook during NASA’s upcoming Artemis lunar mission. With unique knowledge of once pristine environments, current climate change and incipient sea level rise, ongoing biodiversity loss and ecosystem disruption, finite energy and mineral resources, the geoscience profession should arguably have already become a crucial asset in this troubled world.

How to cite: Koster, E. and Gibbard, P.: The most consequential ethical decision for geoscience , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12918, https://doi.org/10.5194/egusphere-egu24-12918, 2024.

The new School of Ocean Futures (oceans.asu.edu) at Arizona State University (Tempe, AZ, USA) has embarked on a novel way of teaching ocean science with a forward-looking philosophy that centers on the current and future states of the ocean. While situated in Arizona State University’s main campus, it leverages the location of its two offshore campuses, the Center of Global Discovery and Conservation Science in Hilo, Hawaii, and the Bermuda Institute of Ocean Sciences (BIOS) in Bermuda. The Ocean Futures programs combine aspects of traditional ocean science teaching with ocean stewardship, partnerships, and Indigenous knowledge, and focus on the communities that live with the ocean and are affected by its rapid change. In this presentation we will introduce the curriculum of the new degree, as well as the challenges encountered, and best practices learned. Novel courses include “Introduction to Ocean Futures”, a capture course that aims at increasing the interdisciplinary knowledge of oceans, while actively seeking to increase diversity and retention in the field via inclusive pedagogical practices, the historical context of oceanography and an emphasis on developing a mindset of empowerment for change. It is followed by “Ocean Communities”, a course that immerses students through an ethnobotanical lens in global mountain to ocean cultural connections, while elaborating on how various human communities engage, exchange, and build relationships with regional resources. The students will receive hands-on aquatic knowledge through field courses at BIOS, the Sea of Cortez, Hawaii, and Antarctica. The curriculum culminates with an ocean workshop and capstone course that will allow the students to work directly with partners to address real-world challenges facing coastal communities and marine systems.

How to cite: Neuer, S., Pfirman, S., Martin, R., Kamelamela, K., Maas, A., and Bates, N.: Ocean Futures: A New Paradigm and Teaching in the Age of Ocean Change, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13965, https://doi.org/10.5194/egusphere-egu24-13965, 2024.

In the Anthropocentric era, the human-driven climate crisis has become a serious global issue. To mitigate the impacts of climate change, it is crucial for humans to adopt a more sustainable way of living. Human behaviors are shaped by their culture, where religious beliefs play important roles. As a result, people turned to religions for addressing with climate change issues.

Seeming to be unrelated, religions and climate issues have found connections through social systems and communication. By endowing climate issues with religions meanings, religions are able to resonate with the ecological crisis and take meaningful actions. Through this "resonance," religions contribute to climate issues by shaping worldviews, establishing sustainable habits, initiating actions, and influencing policies.

Religious communities have recognized the severity of the human-driven climate crisis. Their call for action reflects the fact that Taiwanese society has failed to respond to the climate crisis due to its endless pursuit of consumerism. To deal with the challenges, religious communities have advocated for “Ecological Conversion”, which persuade people to save the nature for the sake of God.

How religions can empirically contribute to environment issues has been a long-discussed topic. However, previous literatures only focus on the Western-Christian World. Countries with religious beliefs other than Judeo-Christian ethics are seldom discussed. To explore the relationship between religion and climate in Asian contexts, this research will focus on Taiwan, a multicultural country with various religions.

Using the sample data from the 2020 Taiwan Social Change Survey, this study aims to explore the relationship between religion and climate by conducting factor analysis and ordinary least squares regressions.

The evidence reveals a weak connection between religions and people's climate attitudes in Taiwan. Among all the religions in Taiwan, Buddhists and Christians tend to have the most eco-friendly attitudes. The social networks within these two religious communities foster an eco-friendly atmosphere, which highlights the importance of environmental conservation. However, when it comes to peoples’ willingness to pay, faith holders are less likely to show their supports.

By illustrating the religion-climate relationship in Taiwan, this study demonstrates how these two fields intersect in a non-Western society. It also provides implications for how religions can inspire people's willingness to engage in environmental conservation efforts.

How to cite: Tsui, C. H.: Do religions matter? The empirical study of the religion-climate relation in Taiwan, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14027, https://doi.org/10.5194/egusphere-egu24-14027, 2024.

Sustainable and responsible management of geo-resources requires a rethinking and redesign of our production and consumption patterns. Awareness of the natural environment as a common good to be preserved, and knowledge of the close link between the natural environment and the socio-economic system are prerequisites for a profound change in human attitudes at both individual and societal levels. In this context, training and education of all actors involved in the management of geo-resources is an indispensable starting point for the acquisition of critical, ethical, and conscious thinking and the technical skills necessary to solve local problems and initiate sustainable development.

The present research focuses on two consequential ERASMUS+ projects: SUGERE and GEODES. Both had the common goal of the international standardization of Higher Education training and teaching in Earth Sciences and Mining Engineering.

SUGERE (Sustainable Sustainability and Wise Use of Geological Resources) was successfully completed in September 2023, involved 3 European universities (from Portugal, Spain, and Italy) and 6 non-European universities (from Mozambique, Cape Verde, and Angola). The objective was to enhance capacity building for the responsible and sustainable use of geological resources by supporting the didactic organization and standardization of 5 degree courses at Bachelor, Master and Doctorate levels in Earth Sciences and Mining Engineering. Both online and face-to-face training sessions were organized in European and African universities.

GEODES, started in June 2023, represents the continuation of the SUGERE project and involves a total of 9 partners. The same 3 European universities and 6 African institutions, formally attributing teaching and training roles to 2 universities that participated in SUGERE, already achieved a good standard in terms of infrastructures and have long teaching experience in the field of geosciences, and receiving 4 young institutions from less favored regions of Angola and Mozambique.

SUGERE and GEODES projects aim to strengthen the role of geosciences in the development of up-to-date strategies for the sustainable management of natural resources and to implement new collaborations thanks to an international network focused on local economic and social development and respect for the natural environment in the geological-mining context. The culture of sustainability and the deepening of skills in the field of geological mining form the basis for the development of the critical thinking necessary for local problem solving, the acquisition of ethical values and the technical skills that underpin sustainable development.

Deepening technical skills in geomining from a sustainable perspective is crucial for developing critical thinking and acquiring ethical values necessary for solving local problems. SUGERE and GEODES contribute to this outcome with a solid network of research, training, sharing and exchange of expertise and research activities between European and non-European universities interested in mining issues. A careful analysis of the local economic development of the countries involved in the projects is required to achieve the most effective methods for the exploration and sustainable exploitation of underground georesources.

How to cite: Dino, G. A., Mancini, S., Pereira, D., Lasagna, M., Gambino, F., Prego, G., Gonçalves, D., Jacinto, A., Jamal, D., Loite, J., Nganhane, H., Rodrigues, N., and Dinis, P.: Towards sustainable management of georesources: the importance of Cooperation Projects to boost education on responsible and sustainable mining. The example of the SUGERE and GEODES projects., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14752, https://doi.org/10.5194/egusphere-egu24-14752, 2024.

Since time immemorial, nature, and by extension the ocean, have made positive contributions to the health of mankind. Whether it be fertile soil, pollination, medicine, taking part in mindfulness activities, or food, we as a species depend on the many services provided by the natural world.  Our environment can be linked to some fundamental determinants of health, such as clean air, clean water, and balanced nutrition, and emotional wellbeing.  Therefore, any environmental degradation as a result of climate change has undeniable tangible and intangible effects on human health all over the globe, and this is especially true in relation to mental health in populations occupying Large Ocean Island States (LOIS).   As climate change has led to an increase in extreme weather events, and the accompanying devastation, there has been a corresponding decrease in health and quality of life.  This presentation will explore how the impact of climate change and its corresponding impact on the ocean has enduring impacts, both physiologically and mentally.   Therefore, all of the processes and recommendations to combat climate
change will have important co-benefits to mental and physical health, and help to build resilience in the face of the dearth of resources faced by LOIS. This lack of resources must be urgently addressed, and solutions can be explored by fostering collaboration between mental health professionals and climate scientists to collect sufficient data. The resulting findings can be used to expedite access to the funds needed to implement the necessary levels of mitigation and adaptation specifically tailored to the infrastructural realities of LOIS.

How to cite: Alvarez de la Campa, S.: Climate Change, Ocean Health and Quality of Life - An Inextricable Connection in Large Ocean Island States, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16730, https://doi.org/10.5194/egusphere-egu24-16730, 2024.

Like numerous regions worldwide, Sri Lanka faces significant environmental challenges that endanger its biodiversity, natural resources, and the well-being of its population. Predominant issues encompass water and air pollution, land degradation, deforestation, improper waste disposal, consequences of climate change, disaster risks, as well as the loss of biodiversity and geodiversity. The nexus between political, economic, and social factors contributes to these geo-environmental challenges, often exacerbated by the politicization of the environmental issues in Sri Lanka. However, it is crucial to acknowledge that human activities primarily drive these conditions. Gunnar Myrdal’s Soft State theory asserts that despite the existence of multiple governing bodies, regulations, and laws, humans strategically transcend the environment leading to the depletion of geo-environmental resources within a context of strong societal inequalities, particularly in developing countries influenced by the historical conditioning of colonial interests by developed nations. A philosophical exploration of this issue emphasizes the pivotal role of human indifference towards the environment and natural resources in causing these challenges. To address this issue effectively, a transformation in people's attitudes is imperative, and education emerges as the most potent tool for this purpose. However, a careful analysis of Sri Lanka's primary and secondary school curricula reveals an absence of a dedicated discipline addressing the philosophical and social dimensions of the geo-environmental matter. In light of this, the incorporation of subjects such as geoethics, which specifically addresses the ethical problems in the human-environment interaction, becomes paramount. Integrating geoethics into the educational framework, particularly at primary and secondary levels, stands as the foundation of a sustainable and responsible strategic approach to many societal and environmental problems. This educational strategy should envision as the most important solution to mitigate the majority of geo-environmental problems in Sri Lanka, fostering environmentally sensitive and responsible citizens.

How to cite: Di Capua, G. and Gunawardana, U.: The importance of making geoethics a central concern of Sri Lankan education strategy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17346, https://doi.org/10.5194/egusphere-egu24-17346, 2024.

After more than 40 years of reasoned alerts from the scientific community directed towards society, with minimal impact, a recent surge in the size and frequency of extraordinary climatic events has begun to reshape the perspectives of ordinary citizens. This situation underscores the challenge of directly influencing society with scientific evidence or models, emphasizing the crucial role of universities in training students who will occupy intermediate or elevated positions that may impact society at large.

While "Climate Fresk" has gained widespread popularity in higher education institutions as an effective tool for raising awareness about climate change and the intricate processes affecting our global earth ecosystem, concerns have arisen at the university level. The repetition of "Climate Fresk" or similar tools may be perceived as greenwashing practices, as university students are already well-acquainted with the issue. Hence, there is a need to surpass mere awareness in higher education.

As TASK Change Leaders at ENS-Lyon, we explored pedagogical and assessment tools provided by Sulitest. This initiative, extends beyond climate and ocean changes, it places a significant emphasis on various topics, including Sustainable Development Goals, earth limits, and driving processes of climate change. One of the major interest of the approach is to address all disciplines (scientific or non scientific).

We built a three-step strategy involving:

• Administering a positioning test to enable students to assess their performance relative to the institution and the wider community.

• Utilizing the looping tool from Sulitest, wherein small teams of students generate Multiple Choice Questions accompanied by a list of academic publications validating the terms of their questions. Subsequently, these questions are discussed in large interdisciplinary open groups, compelling students to articulate questions and answers intelligible across all disciplines.

• Participating in the TASK to receive an assessment of their proficiency in sustainable development, evaluated by an external body.

This strategy, particularly the second step, empowers students to assume the role of a teacher or knowledge spreader in the face of a diverse peer community. It serves as a simulation of their potential future roles as educators, knowledge spreaders or decision-makers, instilling an understanding of the importance of providing validated sources and the challenges associated with crafting questions and answers comprehensible to all, preparing them for future teaching or decision-making scenarios. A notable byproduct is the creation of valuable pedagogical resources in a "connectivist MOOC flavor."

Beyond the training benefits, membership in the TASK Change Leaders group provides opportunities for discussions on the sustainability of education, green education, and competency frameworks, to apply to ourselves the concepts we are teaching.

How to cite: Vidal, G., Eyraud, C.-H., Larose, C., and Lejan, É.: Choice Question (MCQ) Peer Construction for Training Students as Climate Change decision-makers or Knowledge Spreaders, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17614, https://doi.org/10.5194/egusphere-egu24-17614, 2024.

The new Ocean Futures program at Arizona State University (Tempe, AZ, USA) prepares students to become coastal and marine stewards, community leaders, innovators, and researchers capable of shaping the future of the world's oceans.  The program is taught and mentored by faculty and community leaders in an environment that supports our students’ individual and collaborative strengths, creativity, and diversity.  Students learn and work across disciplines, exploring global and local ocean dynamics, ecosystems, and stressors, engaging with community contexts and livelihoods, and advancing culturally-appropriate, reciprocal stewardship.  In support of ASUʻs mission of embeddedness and linking innovation to public value, graduates of the School of Ocean Futures are equipped with the knowledge and skills to work with diverse communities and partners to create innovative solutions for our changing world.

The School of Ocean Futures educational goal is to build student capacity to apply knowledge of coastal and marine systems coupled with community partnerships to help shape thriving futures, both locally and globally.  Students engage in research and work with partners in Arizona, the Bermuda Institute of Ocean Sciences (BIOS) in Bermuda, the Center of Global Discovery and Conservation Science in Hilo, Hawaii, the Sea of Cortez, and Antarctica.

Ocean Futures education at ASU is based on an innovative “cascade” curriculum.  The cascade starts with core classes in Introduction to Ocean Futures and Ocean Communities, followed by foundational courses in sciences and mathematics, an upper-level core class in Oceanography, electives focused on partnerships, stewardship, and advanced problem-solving, and culminates in an applied workshop and capstone course where students work with partners to transfer knowledge to action in addressing problems facing coastal communities and marine systems.

How to cite: Neuer, S., Pfirman, S., Martin, R., Kamelamela, K., Maas, A., Peters, A., and Bates, N.: Shaping Thriving Ocean Futures – Education to advance healthy coastal communities and marine systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20953, https://doi.org/10.5194/egusphere-egu24-20953, 2024.

Fifty years ago, Peter Berg developed a way to locate yourself within your bio-region, starting with your watershed. To begin, trace your water from precipitation to tap—and back to precipitation. Then, how much rain fell in your area last year? How much water does your household consume per month? What percentage of your town’s water supply goes to households? to manufacturing? to farming? to golf courses? to mining operations? to extinguishing fires? What pollutants affect your water supply? Once you can map your local water supplies, consider how manufacturing transistors, operating data storage centers and streaming videos impact international waters. With awareness of our daily lives’ impacts on local and international waters, we can create realistic limits.  

How to cite: Singer, K.: Mapping water from our tap to the watershed: A first step toward ecological limits  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21221, https://doi.org/10.5194/egusphere-egu24-21221, 2024.

How to cite: Marin-Ceron, M. I.: Science Diplomacy with Nontraditional Actors: Enhancing Geo-Bio-Cultural Diversity in Colombian Cities and Territories, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22117, https://doi.org/10.5194/egusphere-egu24-22117, 2024.

Participation in (inter-) national conferences, seminars, and workshops such as the EGU General Assembly is important for professional exchange and personal networking, especially for early career scientists. Enabling scientists with family obligations to take part in conferences will increase gender equity and diversity, as women remain to be the main caregivers in most families.

The questions of family planning and kickstarting a professional career arise simultaneously in almost any field. What makes this particularly challenging for young families in academia is that this line of work frequently requires for parents to move, making traditional forms of supportive caregiving by extended family members often unavailable. The vital role conference attendance plays for an academic career only aggravates that challenge. Therefore, a lack of opportunities to attend conferences and workshops clearly puts young parents at a disadvantage, especially young women in academia.

The Project for Family-Friendly Conferences has been initiated by Leonie Esters and Lisa Schielicke from the Department of Geosciences at the University of Bonn in April 2023. Elena Päffgen joined as a research assistant (WHK) later the same year. With an initial duration of one and a half years the project is funded by the Gleichstellungsbüro (office for equal opportunities) of the university. Our principal goal is to find out, how conference and workshop participation can be made more family-friendly.

The present work analyses an online survey with 245 participants who were interviewed on the topic of family-friendly conferences. The survey was addressed to all scientists with a focus on geosciences, 58% of all participants claimed to have children, while 42% were childless. 61 comments expressing wishes and needs of parents and guardians we received from the participants underscore the urgency of the matter. Key concerns of the participants were clear communication (e.g., whether children could be brought along to the events in question), awareness among event-organizers, and easy access to financial assistance (e.g. for babysitting). For instance, more hybrid events, on-site childcare and designated family-friendly activities at conferences were named as possible improvements. However, considering that families and their challenges are diverse, a wide array of offers and flexibility are required to address their needs.

Our project aims to educate the wider academic community on family-specific challenges. Based on the results of this survey, we will provide conference organizers with guidelines to improve family-friendliness of conferences and facilitate their exchange among each other. Additionally, we want to keep parents informed about the offers for families that are already in place at conferences in our field of study. Overall, we are convinced that outcomes of our project will be beneficial for conference and workshop organizers likewise as for researchers who are parents and will contribute to gender equity and diversity in academia.

Children, parents and guardians are particularly welcome to the poster presentation and discussion.

If you would like to participate in our survey: https://www.empirio.de/s/VxLGGLxWv2

How to cite: Päffgen, E., Esters, L., and Schielicke, L.: Family-Friendly Conferences in the Geosciences, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-410, https://doi.org/10.5194/egusphere-egu24-410, 2024.

The European Geosciences Union (EGU) is the leading organisation supporting Earth, planetary and space science research in Europe, upholding and promoting the highest standards of scientific integrity, open science and open access research. EGU’s vision is to realise a sustainable and just future for humanity and the planet through advances in Earth, planetary and space sciences.

The EGU awards and medals programme acknowledges distinguished scientists every year for their exceptional research contribution to the Earth, planetary and space sciences. Furthermore, it recognises the awardees as role models for the following generation of early-career scientists, encouraging geoscience research. 

Except for EGU council and award committee members everyone (including non-EGU members) is eligible for receiving an EGU award. Nominations need to be submitted by EGU members online by 15 June every year. Each EGU medal or award is selected through a rigorous assessment of the candidates and their merits through the respective committee. The procedures for nomination, selection of candidates and the time schedule are described in detail on the EGU website. 

EGU is committed to recognizing scientific excellence providing equal opportunities. The processes and procedures that lead to the recognition of excellence must be transparent and free of biases. However, establishment of clear and transparent evaluation criteria and performance metrics to provide equal opportunities to researchers across gender, continents and ethnic groups can be challenging since the definition of scientific excellence is often elusive. 

The purpose of this presentation is to share the experiences and efforts of the European Geosciences Union to ensure equal opportunities. The presentation will showcase data and statistics to provide constructive directions towards the objective of offering equal opportunities to researchers from diverse demographic backgrounds.

How to cite: Blunier, T.: Equality of opportunities in EGU recognitions: The EGU Awards Committee experience, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1620, https://doi.org/10.5194/egusphere-egu24-1620, 2024.

Combining an academic career with caretaking responsibilities is an often-overlooked challenge. Juggling the workload, conference attendance, or the potential requirement to move to a new job all become more demanding when children or other caretaking responsibilities are a part of your life. We, members of the Young Hydrology Society (YHS), wanted to hear some views from academic parents in hydrology. What are the challenges they face, what is their advice to other parents and what systematic changes would they like to see? This non-scientific initiative gathered responses from academics within the hydrology community from different parts of the world at different career stages, including PhD candidates, postdoctoral researchers, assistant professors, and group leaders. The survey revealed diverse challenges and strategies employed by academic parents to balance their professional and personal lives. We identified a complex interplay of personal, institutional, and cultural factors that influence these experiences in academia. A common theme across responses was the strategic timing of parenthood, often aligned with phases of planning security, such as after having won a longer-term grant. Despite the varying international backgrounds, many responses highlighted the supportive role of national policies, particularly in countries like Sweden, which offer substantial parental support and flexible work arrangements. However, challenges such as reduced research productivity, lack of support to attend conferences, and the need to relocate were frequently mentioned as limiting factors for career development and progression. Among the strategies employed to minimise these challenges, we highlight adjusting work schedules, reducing workloads, and relying on support from partners and extended family. Childcare distribution varied, with many striving for an equitable split between partners, though this was often influenced by career demands and cultural standards or expectations. The responses also contained suggestions for systemic improvement, including extended childcare facilities at conferences, more flexible job contracts, and institutional support for parents, particularly during fieldwork and conferences. While there are notable advancements in some areas, there remains a significant need for systemic changes to better support academic parents and ensure a more inclusive and equitable academic environment. It is fundamental to highlight, however, that the results of this initiative do not capture the entire spectrum of experiences faced by those with caretaking responsibilities, and that our survey is likely to be biased towards ECS who still were engaged and successful in their work. We aim to release these results as a series of blog posts on the YHS webpage (https://younghs.com/blog/) to disseminate this topic with the main aim of offering valuable reassurance to current and future parents in academia facing similar challenges.

How to cite: Spieler, D., Stein, L., and Nóbrega, R.: Navigating parenthood as an early career scientist: insights and challenges from hydrological sciences, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9435, https://doi.org/10.5194/egusphere-egu24-9435, 2024.

Conferences are places where intellectual and communication standards are shown. Ultimately, they can contribute to create a sense of belonging or inadequateness. However, several analyses of specific diversity measures have demonstrated that large conferences often lack diversity in terms of gender, geographic location or race. The present contribution presents an analysis of the gender, country of affiliation and student status of the participants and presenters during four instances of a small European geoscience conference, as well as the length of presentation and number and tone of questions of the latest instance of this conference. We found that women make up about one-third of participants, session chairs, invited keynote speakers, and presenters (oral and poster) on average, but percentages vary greatly from one year to the next. Students represent around 30% of participants, but over 40% of poster presenters and 28% of long presentations. In total, only half of the participants asked a question, and most of the questions were asked by senior men. Around 25% of the questions were asked with a friendly tone; the remainder were neutrally asked. Friendly questions were asked more frequently after keynote lectures and long presentations than following short talks. We suggest concrete actions that can be taken to promote the development of an inclusive and supportive environment at small conferences.

How to cite: Lefebvre, A. and Bernhard, R.: Diversity at a Small Geoscience Conference, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9557, https://doi.org/10.5194/egusphere-egu24-9557, 2024.

The ADVANCEGeo Partnership program, funded by a National Science Foundation ADVANCE award in 2017, was designed to empower geoscientists to transform workplace climate, and has been recently adapted to other STEMM disciplines as well. To date, the ADVANCEGeo Partnership has led over 230 workshops to institutions across the USA and Europe, in both virtual and in-person formats. A main strategy of ADVANCEGeo for organizational climate change is to enact interventions at the individual and collective level through behavior change education informed by intersectionality and ethics of care frameworks. The program uses a community-based model for bystander intervention and workplace climate education designed to give members of the academic community the knowledge and tools to identify, prevent, and mitigate harm from exclusionary behaviors that directly affect the retention of historically excluded groups in STEMM. 

Evaluation data from 81 workshops held between 2018-2022 were analyzed using a transtheoretical framework of behavioral change. All of these workshops used a consistent structure and length of presentation (averaging 2.5 hours overall). Thirty six workshops were conducted in-person (44%) and forty five workshops were conducted virtually (56%) using the Zoom platform. The workshops were conducted for a variety of audiences, including institutional leadership, academic departments, professional societies, research groups, and student groups. Each workshop included the same core components, though some materials in the presentation portion were tailored to the needs of the audience as requested. Evaluation results show positive increases in participant knowledge, satisfaction, and intent to change behavior directly after the workshop. An additional follow up survey that was disseminated approximately 6 months after the workshop provides evidence of longitudinal behavior change. These results demonstrate that the ADVANCEGeo Bystander Intervention model design successfully shifts behaviors in workshop participants, with an aim to create more positive workplace climates for all seeking to be a part of STEMM.

How to cite: Schneider, B., Bell, C., Whitmire, S., Hannah, H., Hastings, M., Barnes, R., Mattheis, A., Williams, B., and Marin-Spiotta, E.: An Evaluation of the ADVANCEGeo Partnership Bystander Intervention Model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10508, https://doi.org/10.5194/egusphere-egu24-10508, 2024.

The International Association of Hydrogeologists (IAH) is a scientific and educational charitable organisation for scientists, engineers, water managers and other professionals working in the fields of groundwater resources planning, management and protection. Comprising various commissions and networks, IAH engages in activities such as contributing to groundwater science, outreach, education, and training. While IAH takes meaningful steps towards equity, diversity, inclusion, and accessibility, recognising the importance of putting these principles into practice, it is essential to acknowledge that there are still numerous challenges and barriers that need to be addressed. It is worth noting that IAH shares similar challenges with many other organisations and associations in navigating the path towards greater equity, diversity, and inclusion. Therefore, the establishment of a dedicated working group became imperative to address and overcome these challenges effectively.

The Socio-Hydrogeology Network (IAH-SHG), an official IAH network, aims to integrate social sciences into hydrogeological research, and has two active working groups: the Working Group on Groundwater and Gender, and the newly established Equity, Diversity, Inclusion, and Accessibility (EDIA) Working Group. This group is designed to further enhance the EDIA landscape within the IAH and beyond. It is the result of collaborative endeavours, extensive discussions, and productive meetings within the IAH and IAH-SHG, and it builds on the work and experience of the Working Group on Groundwater and Gender and the IAH-SHG in general. We will showcase the key insights gained from our IAH-SHG experiences and demonstrate how we applied these lessons to facilitate the establishment of the EDIA Working Group.

By harnessing the power of collective effort, the EDIA Working Group aims to foster a positive impact that resonates throughout the IAH and wider hydrogeological community. We will present our experience regarding the pivotal role of networks, such as IAH-SHG, in advancing equity, diversity, inclusion, and addressing barriers within the geosciences. We will also share our plans for collaboration with other IAH commissions, networks, IAH members, and other individuals (i.e. membership in the IAH is not a prerequisite for individuals interested in joining the IAH-SHG or any of its working groups), as well as ideas and recommendations for new and innovative strategies to identify and overcome barriers. Furthermore, we will share the EDIA Working Group's experience so far, providing insights that may be valuable for other associations, organisations, and groups facing similar challenges.

How to cite: Vucinic, L., Re, V., Zambelli, B., Frommen, T., Ajia, F., and Limaye, S.: Promoting and Supporting Equity, Diversity, Inclusion, and Accessibility: A Collaborative Approach in the Hydrogeological Community and Beyond, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11929, https://doi.org/10.5194/egusphere-egu24-11929, 2024.

The study of inland waters - Limnology - is full of fascinating women who have vastly contributed to our understanding of these valuable ecosystems. Although women’s visibility was low during the early years of Limnology, it has increased over time. Nowadays, women represent half of the early-career limnologists in Europe. However, as in many other fields, their scientific contributions have been traditionally neglected from schools to universities (i.e., the Matilda effect). The project “Gender LimnoEdu”, developed by the Gender&Science AIL group and funded by EGU (2020), aims to increase the visibility of women in Limnology and related subjects - such as Ecology, Hydrology or other Geosciences - in academic courses and lectures. We have created a set of online ready-to-use resources: (1) a self-evaluation form to detect gender biases and raise self-awareness for teachers of Limnology and Geosciences courses (the form is applicable to a wide range of courses and disciplines), (2) teaching nutshells highlighting key female limnologists (and their history) to help lecturers to acknowledge the role of women in Limnology in their courses, and (3) a complete teaching unit about the past and present situation of women in the field of Limnology. All these resources are freely available (https://www.genderlimno.org). Here, we will present this toolbox of resources and guide you on how to use them for your teaching needs. Moreover, we will share the preliminary results of the self-evaluation form to showcase how gender-fair Limnology lessons in high-education courses are. We welcome everybody to take it! https://www.genderlimno.org/gender-fair-lessons.html

How to cite: Poblador, S., Anton-Pardo, M., Bartrons, M., Benito, X., Bernal, S., Bohorquez Bedoya, E., Cañedo-Argüelles, M., Catalán, N., Fernandes, I., Freixa, A., Genua-Olmedo, A., León-Palmero, E., Lupon, A., Mendoza-Lera, C., Pastor, A., Rodríguez-Lozano, P., Zufiaurre, A., and Sánchez-Montoya, M. M.: Is my teaching gender-fair? A self-assessment questionnaire., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12182, https://doi.org/10.5194/egusphere-egu24-12182, 2024.

Many universities openly pledge commitments to improving diversity, with science, technology, engineering, and math (STEM) fields receiving significant attention. Despite these efforts, geoscience remains one of the least diverse fields in STEM. This recognition has prompted an increase in studies stressing the systemic lack of representation across the field and the barriers that exist for those within. However, much of this work has been limited by the use of demographic datasets that have been either passively collected or derived from government sources. Constraints include country-specific data collection policies, failures to collect field-specific data, and the absence of additional information necessary for intersectional analysis. Advancing diversity, equity, and inclusion (DEI) in our field requires meaningful datasets that clearly identify social inequalities. Limited, incomplete, or anecdotal data are too easily dismissed by those in power, stalling constructive efforts.

In Canada, demographic data is not regularly collected at academic institutions and is seldom field-specific. This absence of data undermines efforts to identify the current state of diversity in the field and prioritise initiatives for improvement. Collecting comprehensive demographic data is a crucial step in determining whether progress is evident. It can also help to highlight areas of concern, especially in fields lacking in diversity, such as geoscience. To address this absence of data, we disseminated a 22-question demographic survey to 35 academic geoscience departments across Canada in late 2022.

We received 482 eligible responses to the survey, accounting for approximately 20% of the research population. Overall, men make up a slight majority across all respondents (53%), and the percentage of individuals who identify as white (73%) is greater than the national average (67%). Additionally, results shows that research students (MSc and PhD) are a diverse group, while salaried positions (postdoc, research staff and faculty) lack diversity in a wide range of categories including, gender, race, LGBTQ+, Indigeneity, and disability. Moreover, tenured positions are overwhelmingly occupied by white men, with racial inequalities prominent in the data.

These data highlight several areas of concern in the academic career path. The transition from research student to salaried research remains a clear area of concern, while the tenure process appears to continually favour white able-bodied cisgender men. Moreover, the representation of Indigenous persons and those with self-identified disabilities remains very low. Solutions require institutional changes to recruitment, tenure applications, postdoctoral hiring, field work design, and mentoring practices. Importantly, they also require changes to how we collect and analyse demographic datasets in geoscience, as a continued reliance on data that is passively collected or obtained from government sources will continue to limit our abilities to identify areas of concern and create effective strategies.

How to cite: Jess, S., Heer, E., and Schoenbohm, L.: Active demographic data collection in geoscience: results, implications, and recommendations from a survey of Canadian academia  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12643, https://doi.org/10.5194/egusphere-egu24-12643, 2024.

The American Geophysical Union understands an expansive and inclusive geoscience community is key to furthering knowledge about the Earth and the universe and finding solutions to current societal challenges. Though the geosciences have historically been dominated by a few homogenous groups, the collaborative and global nature of our science impels us to change our systems to include historically marginalized voices. Supported by AGU’s 2018 Diversity and Inclusion Strategic Plan, in 2023, AGU Publications signed the Joint Commitment for Action on Inclusion and Diversity in Publishing.  Signatories agree to collect self-reported gender and race/ethnicity data, develop baselines, and set minimum standards for inclusion. We provide a demographic overview of our authors, reviewers, and editors over time, detail how we collect data while following privacy laws, and discuss how data informs our DEIA strategies. We provide reports to our journal editors who set baselines and develop journal goals. We launched various initiatives to increase diversity and equity and decrease bias in peer review processes, and used the data to assess outcomes of these initiatives. In addition, we present examples of policy and structural changes we have implemented to weave DEIA in the scientific publishing environment, including our equitable approach to Open Access, our Community Science Exchange, and the recently launched Inclusion in Global Research policy to improve equity and transparency in research collaborations.

How to cite: Giampoala, M., Ricci, M., and Wooden, P.: Embedding EDI in Geoscience Publications – Examples from the AGU , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13028, https://doi.org/10.5194/egusphere-egu24-13028, 2024.

The equality and work well-being group at the Institute for Atmospheric and Earth System Research (INAR) at the University of Helsinki conducted a survey about academic household work (AHW) tasks among the institute’s staff in autumn 2023. The main aim of the survey was to find out how different AHW tasks are divided among the staff members and how the staff members consider these tasks.

Before the actual survey, we asked the staff to list tasks they consider AHW (nakkihomma in Finnish; direct translation: Frankfurter task). A few examples of AHW tasks we got: sending calendar invitations for meetings, making coffee for others, helping to organize social events at the institute, emotional service work (being involved in discussion with colleagues or students about their personal affairs or problems). For the survey, we grouped the proposed tasks in three categories (number of tasks in parentheses): research-related tasks (3), society-related tasks (4) and community-related tasks (29). The last category was further divided into four subcategories: tasks related to meetings (7), social events (6) and facilities (9), and miscellaneous (7). We asked which tasks the staff members consider as AHW, and how frequently they are committed to each task.

We received a total of 91 answers to the survey. This corresponds to 33% of our staff, but according to the background information we collected, the different groups in terms of gender, career stage, language status (Finnish/non-Finnish speaker) and staff group (research/technical/administrative) were represented well.

The general attitude towards AHW was surprisingly positive: 57% of respondents had a positive attitude while 35% had a neutral attitude. Senior research staff members use a considerable amount of time participating in different committee meetings while early-career researchers do not so much; however, they do a great deal of practical duties related to meetings. Furthermore, we found out that a lot of emotional service work is being done. Interestingly, early career researchers do not consider this generally as AHW while senior researchers do. Male staff members contribute more to technical writing and guiding tasks while female staff use more of their time in emotional service work and general collective AHW tasks. Finnish speakers contribute more to writing and guiding tasks while non-Finnish speakers are more frequently committed in “catering” AHW like making coffee. Technical and administrative personnel generally contribute more to AHW than research staff.

We hope that the results of this survey will help us developing a more equitable and inclusive atmosphere in our institute by enabling us to pay more attention in distributing AHW tasks in a more equal and just manner.

How to cite: Lauri, K. A., Li, X., Dukat, P., Atashi, N., Karppinen, L., Lehtipalo, K., Lintunen, A., Moisseev, D., Mukkala, J., Nieminen, T., Rantanen, R., Vesala, T., Ylivinkka, I., and Vehkamäki, H.: Nakkihomma: attitudes towards and distributions of academic household work, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14684, https://doi.org/10.5194/egusphere-egu24-14684, 2024.

The European Research Council (ERC), Europe’s premiere funding agency for frontier research, views equality of opportunities as an essential priority and a vital mission to ensure fairness in the review process. The ERC monitors various demographic data yearly on every call and has taken actions to tackle imbalances and potential implicit and explicit biases.

The presentation focuses on ERC general historical data for the three individual funding schemes: Starting Grant, Consolidator Grant and Advanced Grant. Demographic geosciences data of proposals and grants, disaggregated by gender and country, is presented. After more than 14 years of existence and various specific actions to tackle societal imbalances, ERC data provides an insight of the impact of various actions.

In the first framework programme (FP7, 2007-2013), 25% of applicants were women. In the last years (Horizon 2020, 2014-2020), this percentage increased by 4%, with 29% of women applying for ERC grants. In the same periods of time, the share of women as grantees has also increased from 20% to 29%. In the last years, men and women enjoy equal success rates (data for non-binary applicants is also presented).

The most recent actions taken by the ERC to address gender and diversity (including disabilities and neo-colonialism) in its operations and processes are also presented.

The ERC knows that work to ensure inclusive excellence and equality of opportunities is never-ending. This presentation analyses the institutional efforts critically and discusses possible steps to consolidate the accomplished results.

How to cite: Jesus-Rydin, C., Fariña-Busto, L., and Jansen, E.: Inclusive excellence at the ERC: latest actions and results of sustained measures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16168, https://doi.org/10.5194/egusphere-egu24-16168, 2024.

How to cite: Cano, M., van Zelst, I., and Shivkumar, H.: Science Sisters: Interviews with diverse role models on career paths and academic life, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17197, https://doi.org/10.5194/egusphere-egu24-17197, 2024.

Young Women of Geoscience (YWOG) is a group of young professionals (PhDs, postdocs, assistant professors and supporting staff) at Utrecht University with the aim to inspire, connect and support women and historically underrepresented groups in the field of geosciences, by creating an equal and inclusive working environment. We do this by opening up conversations and creating a safe and positive space for discussion. Now in our seventh year, the committee has established itself as a constant and stable presence within the faculty with regular events and initiatives that can easily be organized from our reputable base.

Our regular events consist of meet-and-greet sessions with senior staff members, that are well-attended by a variety of colleagues, which result in inspiring conversations. Additionally, book give-aways combined with book discussions are a recurring event, where books on diversity, inclusions and climate change are used to open conversations. These events often engage individuals who may not have initially identified with the committee's target audience, but afterwards their interest was sparked. In recent years we also organized successful events due to requests from staff members. Parenting during COVID was a successful online event with a panel discussion consisting of colleagues sharing tips and struggles. Additionally, this year we organized an event on pronouns, reaching a wide audience, from PhDs to supporting staff, professors and the faculty dean. It was also this session, with informative presentations and lively discussion, that led to immediate action from higher level staff on practical matters concerning pronouns in the workplace.

Our experience highlights the importance of a bottom-up approach in instigating meaningful change. The pronouns event is a prime example of this, opening the eyes of many attendees and making people feel the urgency for action. The event stemmed from a need within the faculty. However, to be able to organize such an event there must be a platform to do so. We have the opportunity to organize many events helped by funding through an Equality, Diversity and Inclusion (EDI) scheme and an internal award won by the committee. We aim to continue with the regular events like the meet-and-greets and book shares, and hope to organize more events that are based on the needs in the faculty to open conversations. YWOG's experience demonstrates the efficacy of a bottom-up approach, emphasizing the importance of diverse perspectives in fostering substantial changes toward a more inclusive working environment. The committee looks forward to sharing its experiences, connecting with other faculties and universities, and inspiring collective efforts to promote diversity and inclusion within geosciences.

How to cite: Verberne, M., Cox, J. R., Dunn, F. E., Postma, M., and Venema, T.: Time’s up, bottom-up! A successful bottom-up approach for diversity and inclusions at Utrecht University, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18544, https://doi.org/10.5194/egusphere-egu24-18544, 2024.

Over the last decade, the way we communicate and engage with one another has changed on a global scale. It is now easier than ever to network and collaborate with colleagues worldwide. But, the COVID-19 pandemic led to a rapid and unplanned move to virtual platforms, resulting in several accessibility challenges and the inadvertent exclusion of several people during online events. While virtual/hybrid events have strong potential to facilitate new opportunities and networks for everyone, they are also greatly positioned to increase the inclusion of groups traditionally excluded from purely in-person conferences. However, early and careful planning is needed to achieve this, with inclusion and accessibility considered from the start. Including a virtual element in a conference does not automatically equal inclusion or accessibility. Without effective planning, virtual and hybrid events will replicate many biases and exclusions inherent to in-person events.

This presentation will share lessons learned from previous events’ successes and failures, based on the combined experiences of several groups and individuals who have planned and run such events. This presentation is based on an EGU Sphere article, of the same title, that aims to provide guidance on planning online/hybrid events from an accessibility viewpoint based on the authors experiences. The goal of this presentation is to initiate discussion on event accessibility and inclusion and to help generate new ideas and knowledge from people outside of the authors network. Every event is unique and will require its own accessibility design, but early consideration is crucial to ensure everyone feels welcome and included. Our suggested accessibility considerations have been broken down into three stages of event planning: 1) Pre-event planning, 2) on the day/during the event, and 3) after the event.

Ensuring accessibility and inclusivity in designing and running virtual/hybrid events can help everyone engage more meaningfully, resulting in more impactful discussions including groups with limited access to in-person events. However, while this article is intended to act as a starting place for inclusion and accessibility in online and hybrid event planning, it is not a fully comprehensive guide. As more events are run, it is expected that new insights and experiences will be gained, helping to continually update standards.

How to cite: Doran, A., Dutch, V., Warren, B., Watson, R. A., Murphy, K., Aldis, A., Cooper, I., Cockram, C., Harp, D., Desmau, M., and Keppler, L.: Planning virtual and hybrid events: steps to improve inclusion and accessibility, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20027, https://doi.org/10.5194/egusphere-egu24-20027, 2024.

The percentage of female scientists in Japan is 17.5% in the 2021 survey. This percentage is the lowest among OECD countries. The percentages of female doctoral students in science and engineering graduate programs nationwide are 21.0% and 19.2%, indicating a gap between the percentage of female prospective researchers and the percentage of women actually employed. It is pointed out that this is due to gender bias at the time of recruitment. On the other hand, the percentage of female members of JpGU remains around 20%, which is higher than the average in Japan, but still low compared to the percentage of female geoscientists in EGU and AGU. One of the reasons for the low number of female scientists in Japan is the low percentage of female students entering science and engineering fields in Japan (27% in science and 16% in engineering). The Science Council of Japan's Subcommittee on Gender and Diversity in Science and Engineering analyzed this problem and pointed out that its cause lies in the environment of education system during elementary and junior high schools (Opinion of SCJ, 2023). In Japan, the following factors are considered to have contributed to the decline in the number of female students going on to study science and engineering, even though surveys such as PISA (2018) and TIMSS (2019) show that both male and female 15-year-olds have equal academic achievement and interested in science and mathematics in the early education stage. (1) The percentage of female science teachers in junior high school and above is significantly lower than in the OECD countries → Few role models. (2) Often exposed to obvious “implicit bias” that has no evidence to support it (for example, girls are not good at mathematics. Science and engineering professions are not suitable for girls).

JpGU and Japanese universities actively conduct outreach programs for female junior igh and high school students every year to foster future female scientists. However, only a small percentage of them in whole Japan participate in such events, and these initiatives does not give us a full solution.

How to cite: Hori, R. and Oguchi, C.: The stagnation of low percentage of female scientists in Japan and JpGU's initiatives, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20337, https://doi.org/10.5194/egusphere-egu24-20337, 2024.

The EGU recognises the importance of equality, diversity, and inclusion as a crucial foundation for scientific research to address fundamental scientific questions and societally relevant environmental challenges. The increasing diversity of our membership in all its facets fosters collaborative research and discovery that benefits humanity and our planet.

Since its founding, the EGU has worked to ensure equitable treatment for everyone in the community with the goal of increasing diversity. In autumn 2018, the EGU Council established a working group whose aim is to promote and support equality, diversity, and inclusion (EDI) in the Earth, planetary, and space sciences, with a focus on EGU activities. Less than three years later, the EDI group was upgraded into a committee and has delivered numerous actions.

The most recent achievements of EDI@EGU are the Champion(s) for Equality, Diversity and Inclusion Award that is bestowed to recognize excellent contributions to put into exemplary practice the principles of EDI. Furthermore, the EDI Committee is currently working on a new travel support scheme to promote diversity at the EGU General assemblies.

The above actions resulted in a more diverse attendance at EGU General Assemblies along the years. The total number of presenters has increased over the time period 2015-2023, and this increase was observed throughout all career stages. The proportion of women presenters has increased from 2015 to 2023. A similar trend was observed for the convenors, an increase in total numbers over the years and a higher proportion of women in 2023 than in 2015.

In the hybrid meeting in 2023 both early career scientists and more senior scientists to a higher extent participated physically in the meeting than online. While there were no differences in how women and men participated (online or physically), there are differences connected to the country affiliations. More than half of participants from countries in most of western Europe attended in Vienna, while participants from North America and Asia attended online.

Since EGU General Assembly is the largest geosciences conference in Europe understanding the demographic evolution and their participation to EGU activities, including the GA, of various groups is an important tool for EGU governing body to draw targeted actions to ensure that the current procedures are fair and that all in the community are being and feeling included. We therefore aim to analyse the changes in demographics with regards to gender, career stage as well as to geographical distribution of the presenters and convenors also in coming years to better understand the potential impacts of meetings organized online or physically, or as a combination of both these modes.

How to cite: Stadmark, J., Montanari, A., and Slomp, C.: Signatures of Equality, Diversity and Inclusivity at EGU General Assemblies, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-22185, https://doi.org/10.5194/egusphere-egu24-22185, 2024.

Land degradation is a primary form of global environmental deterioration. Soil erosion and land desertification are common land degradation processes in many regions. In this research, we take the Zhuoshui River basin in central Taiwan as the study area, and investigate the environmental sensitivity of different land use/land cover to land degradation subjected to historical and future climate scenarios. In order to understand the quality of land resources in the study area, we used the evaluating framework of the Mediterranean Desertification and Land Use (MEADALUS) model with revisions according to the localized mountainous characteristics in central Taiwan, and calculated the Environmentally Sensitive Areas Index (ESAI) of the study area. The ESAI is comprised of five indicators, which include climate, soil, vegetation, management, and landslide indicators. For the climate index, observed data from 2001 to 2020 of weather factors were used in the historical scenarios. On the other hand, data of weather factors generated by MIRCO5 GCM considering RCP2.6 and RCP8.5 scenarios in near-term and long-term time scales were used for the climate indicator in the future scenarios. The results depict the spatial variation of environmental sensitivity to land degradation in the Zhuoshui River basin using numerical values ranging from 1 to 2, where higher values correspond to more severe degradation. It is evident that the upper reaches of the Zhuoshui River exhibit lower degrees of land degradation due to dense vegetation, higher elevations, and limited human presence. In contrast, the downstream areas show a higher trend of land degradation, with the wet season exhibiting lower degradation trends compared to the dry season. Furthermore, there is a slight upward trend in land degradation since 2015, primarily attributed to climate indicators, as soil and vegetation indicators, as well as anthropogenic management indicators, show no significant changes. The land degradation index shows relatively subtle differences between future scenarios and historical scenarios, with land degradation index variations ranging from -13% to 22%. Negative values in the degradation index differences indicate an improvement in the degree of degradation, while positive differences denote an exacerbation of land degradation. According to the land use distribution in the Zhuoshui River basin, the land degradation trends for forests and national parks show relatively consistent variations between the dry and wet seasons. However, in the middle and lower reaches of the basin, apart from the RCP85 scenario for the long-term period, the other three scenarios exhibit higher differences in land degradation index changes for agricultural and urban areas compared to historical values. The research provides a reference for preventing continued land degradation and conserving terrestrial ecosystems and biodiversity in the study area.

How to cite: Wang, Y.-C. and Lu, Y.-H.: Evaluating the environmental sensitivity to land degradation: a case study in central Taiwan, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8, https://doi.org/10.5194/egusphere-egu24-8, 2024.

Mapping Ephemeral Gullies (EGs) is essential for enhancing the management and conservation of natural and agricultural resources. This study aimed to devise a novel approach utilizing the Dempster-Shafer (D-S) theory to achieve more accurate EGs mapping. To accomplish this, a high-resolution satellite image and ground data collected during a field visit to the Niagara region in Canada were utilized. Firstly, spectral features that effectively identify EGs were extracted from the satellite imagery. Subsequently, three machine learning classifiers including the artificial neural network (ANN), support vector machine (SVM), and random forest (RF) were employed to generate the EGs map. Finally, the D-S theory was applied to integrate the outcomes from these classifiers, aiming for a more precise EGs map. The results highlighted that the most significant variable importance was attributed to the Normalized Near-Infrared (NIR) (18%) and Soil line (15%). The average producer and user accuracies for the EGs and non-EGs classes across the three classifiers were 0.53 and 0.67, and 0.97 and 0.95, respectively. Incorporating the D-S theory enhanced these accuracy values by 0.15 and 0.19 for EGs and 0.02 and 0.02 for non-EGs. Furthermore, the overall accuracies for the EGs maps generated by the ANN, SVM, RF, and D-S theory models were 94%, 93%, 95%, and 97%, respectively. The results of this study showed that D-S theory is useful for improving the EGs mapping using remote sensing data.

How to cite: Fathololoumi, S., B. Vasava, H., Daggupati, P., and Biswas, A.: Application of Dempster-Schafer theory for predicting ephemeral gullies with remote sensing data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-44, https://doi.org/10.5194/egusphere-egu24-44, 2024.

Rill erosion is one of the most significant water erosion types in the agricultural areas as a complex type of concentrated flow erosion process. And, it is known that hydraulic conditions are closely related to rill development in terms of the initial soil moisture contents. However, the impact of the subsoil hydrology on sediment discharge potentials is somewhat entangled. Thus, many recent studies point out that the change in soil erosion depends on hydrological conditions in the subsoil and suggest that the evaluation of those changes would increase the success of soil erosion estimates to more efficiently manage natural resources. This study was aimed to investigate the effects of different soil moisture settings (referred as dry, saturated and drainage) on rill erodibility (Kr) and critical shear stress (τcr) values of the soils as the significant variables of process-based WEPP model, and the relations between basic soil properties (e.g. particle size distribution, aggregate stability, soil mechanical cohesion, organic matter etc.) and these model variables for the heavy textured 12 soil types (clay contents change between 33 and 52 %). Flume experiments were performed by using a V-shaped mini-flume apparatus, which was 0.046 m wide, 0.5 m long, and 0.12m deep, specifically designed for rill experiments. Two V-shaped channels with a length of 0.2 m were cemented to the flumes, one on each side. The soil samples were packed in boxes to attain natural bulk densities of the soils after passing through a 2 mm screen opening. The slope steepness was set to 3% for the slope bed and the flow rate was controlled with a flow meter from 0.10 L min^-1 to 0.65 L min^-1. Within the scope of the study, the mechanical soil cohesion values of the soils were determined by the fluidized bed approach. Obtained results clearly showed that the initial moisture contents had significant effects on sediment concentrations. The lowest Kr values were observed for the drainage condition in all soils while the highest Kr value was obtained for the soils with higher clay than silt content in the saturated conditions. Under dry conditions, on the contrary, the latter reversed and there was the highest Kr value for the soils having higher silt contents than clay. The inverse relationship between Kr and τcr was very pronounced and the highest τcr value was measured under drainage conditions. In addition, it was observed that there were significant correlations between rill erodibility (Kr) and silt contents and mechanical soil cohesion variables of the soils. Conclusively, rill erodibility potential of the soils observed under concentrated flow conditions had statistically close relationships with initial moisture conditions and primary physical soil properties (p<0.01). The research findings experimentally confirmed that variations in subsoil hydrology would play a crucial role in new generation studies of process-based modelling of the rill erosion.

Key words: Rill erodibility, critical shear stress, WEPP, initial soil moisture content

Acknowledgements: This work was supported by the Scientific and Technological Research Council of Turkey [TUBİTAK-3001, Project no: 118O111].

How to cite: deviren saygin, S., Ari, F., Temiz, C., Arslan, S., Unal, M. A., and Erpul, G.: Effects of the Initial Soil Moisture Contents on Rill Erodibility and Critical Shear Stress of the Clay-rich Soils  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-190, https://doi.org/10.5194/egusphere-egu24-190, 2024.

Soil erosion poses a significant threat to agricultural and natural resources. Soil water repellency (SWR), namely the resistance to wetting due to hydrophobicity, has become widespread due to variety of processes including droughts, wildfires, pollution and greywater irrigation. Recent studies showed that that SWR exerts a strong effect on soil erosion by its hydrological impact: reduction in infiltration implies increase in overland flow, the driving force for erosion. Another, much less explored and more complex effect of SWR on erosion is through its impact on soil cohesion and strength, the resisting force for erosion. Here, we focus on the combined effects of SWR on erosion. We compile the published experimental data of erosion in hydrophobic soils, which provides contradictory evidence of both increase and decrease of erosion with increasing SWR. We find that while drought- and fire-induced SWR predominantly increases erosion, there is no clear trend for pollution-induced SWR, suggesting that pollution can improve the soil’s resistance to erosion, and that this mechanical effect of SWR is stronger than the hydrological effect of increased overland flow. We establish a rational connection between the SWR and its hydrological and mechanical effects on erosion through a simple 1D numerical model. The results of the model indicate that the net erosional impacts of SWR depends on the balance between the soil hydrological and soil mechanical effects of SWR. The key insights obtained from literature and this straightforward model enhanced our understanding of the dual nature of SWR's influence on soil erosion dynamics.

Keywords: Cohesion, Erodibility, Hydrophobicity, Hydrology, Runoff, Soil Erosion

How to cite: Fallah, M., Van De Wiel, M., and Holtzman, R.:  Soil Hydrophobicity Effects on Soil Erosion: Interplay between Hydrological and Mechanical Effects, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-890, https://doi.org/10.5194/egusphere-egu24-890, 2024.

As a result of intensive agricultural practices, cultivated soils of the European loess belt can experience high levels of degradation by erosive runoff. Given the sometimes severe and costly on- and off-site impacts, the agricultural community is urged to adopt alternative cropping techniques to mitigate runoff and erosion. Several cropping practices related to conservation agriculture are known for their ability to mitigate surface flows, but the magnitude of their effectiveness is associated with a wide variability due to environmental or management factors. The influence of these factors on the practices’ effectiveness is still poorly understood in quantitative terms. We therefore quantitatively reviewed the effectiveness of three common conservation farming practices at controlling runoff and soil loss. A systematic search was performed, focused on the plot scale and the Western European context, and meta-analyses were carried out on the 35 collated relevant studies involving 239 individual trials (plot-years). Two different approaches suitable for hierarchically structured datasets were used for the meta-analyses: hierarchical nonparametric bootstrapping and linear random effects models. Both methods yielded very similar outcomes, but the lack of primary data sometimes restricted the ability to account for all hierarchical levels of the dataset in the random effects models. We found that, on average, winter cover crops decrease cumulative seasonal (autumn-winter) runoff by 68% and soil erosion by 72% compared to a bare soil. The level of stubble tillage on the control plot, the number of successive years of cover cropping, and the maximum vegetation cover reached are three key variables explaining the mitigation effect of winter cover crops. In potato crops, tied-ridging (=(micro)basin tillage) cut cumulative seasonal (spring-summer) overland flow by a mean of 70% and soil loss by 92% compared to conventional furrows, but no moderators could be identified to explain the variability across studies or trials. Conservation (non-inversion) tillage techniques alleviate cumulative seasonal runoff by 27% and associated sediments losses by 66% on average, but a publication bias is strongly suspected for this meta-dataset. These mitigation effects are much greater for spring crops than for winter crops, and increase over time since ploughing stopped. The type of conservation tillage schemes also affects the capacity to attenuate surface flows. Intensive non-inversion tillage schemes based on multiple (powered) tillage operations turns out to be the least effective at reducing both water and soil losses. The best performing scheme against runoff appears to be a deep non-inversion tillage (-61%), while against erosion it would be a direct drilling system (-82%). Coarser-textured soils (sandy loam) also respond slightly better to conservation tillage than (clay-)loams. Although several factors could partly explain the effectiveness of two of the three conservation practices considered in this study, there remains a high (unexplained) variability between trial effect sizes, thus not attributable to sampling variability. Meanwhile, this review provides farm advisors or policy makers with guidance on the conditions in which such conservation practices are expected to achieve the greatest benefits.

How to cite: Clement, T., Bielders, C., and Degré, A.: Effectiveness of conservation tillage, tied-ridging, and winter cover crops at controlling runoff and soil loss in the Western European context: a meta-analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2129, https://doi.org/10.5194/egusphere-egu24-2129, 2024.

Past nuclear weapons testing and nuclear power plant accidents resulted in the ubiquitous deposition of radionuclides in the environment. While the risks associated with radionuclide contamination are apparent, these fallout radionuclides (FRNs) provide the privileged markers (“golden spikes”) of the Anthropocene stratigraphic layers. The onset of their emissions in the 1950s coincided with the “Great Acceleration”, which is characterized by large-scale shifts in the biophysical and socio-economic aspects of the Earth System, including an increase in soil degradation, triggered mainly by land-use change. Among the host of FRNs deposited globally, ¹³⁷Cs has been the most commonly used and ^239+240Pu is a new emerging tracer and chronological marker to assess soil erosion and/or chronology of sediment deposition.

In this meta-analysis, we compiled existing ¹³⁷Cs and ^239+240Pu data analyzed from undisturbed soils in the literature to get an overview of the spatial distribution and constraints of fallout ¹³⁷Cs and ^239+240Pu in Equatorial and Southern Hemisphere soils, as well as the possible sources of these FRNs through their isotopic ratios. A database composed of 1087 reference cores was built from the literature published on Equatorial and Southern hemisphere soils.

Aside from the cores collected from the north equatorial regions, high ¹³⁷Cs inventories were also found in reference soils collected at the 40-50° S latitudinal band, which were mostly from South America. On the other hand, high ^239+240Pu inventories were found at the 20-30° S latitudinal band, but this was influenced by the unusually high inventories measured from the French Polynesia, where many nuclear weapons testing occurred. The ^240/239Pu atomic ratios indicated that sources other than the global fallout (^240/239Pu = 0.18) contributed to the reference inventories in the Southern Hemisphere. As some areas lacked measurements, specific points where additional data could be obtained were identified through a GIS-based approach to represent the entire land surface areas of interest adequately. Together with new measurements, the compiled reference soil data will be used to construct a detailed baseline map of ¹³⁷Cs and ^239+240Pu fallout mainly for regional soil erosion assessments.

How to cite: Dicen, G., Guillevic, F., Chaboche, P.-A., Meusburger, K., Sabatier, P., Evrard, O., and Alewell, C.: Spatial distribution of fallout 137Cs and 239+240Pu in Equatorial and Southern Hemisphere soils, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3077, https://doi.org/10.5194/egusphere-egu24-3077, 2024.

Erosion is recognized as a major threat worldwide and can be dramatically observed in Northwestern France as a consequence of water runoff. Recent regional studies in Normandy suggested that off-site erosion and runoff impacts led to significant economic costs over the last 25 years. Even if the regional planning strategy against erosion and runoff impacts could be seen as effective with a cost-benefice balance greater than 1, this strategy will no longer be as effective by 2050 due to climate change effects in the near future. To address this issue and conduct efficient land and water degradation neutrality strategies, local stakeholders now have to identify complementary strategies based on the deployments of nature-based solutions. However, there is a lack of references on the effectiveness of these complementary strategies.

In this study, we conducted a modelling exercise with the WaterSed model at the regional scale (12,318 km²) aiming to: (i) quantify the hydro-sedimentary transfers reaching the karstic systems throughout the 15,000 sinkholes distributed across the territory, (ii) established the first regional cartography of vulnerability of sinkholes to runoff and erosion, and (iii) to evaluate the effectiveness of strategies considering nature-based solutions to prevent land and ground water degradation.

The model was calibrated and validated using data of hydro-sedimentary transfer monitoring station on a local catchment. Multiples scenarios were explored (impacts of different nature-based solutions densities, localization of grasslands, ploughing of grass lands, soil and water conservation techniques, etc.) using semi-automatic positioning algorithm.

The WaterSed model provided specific outputs like volume of runoff (m³) and volume of sediments (t) reaching the karstic system for different designed storms. The mean runoff per sinkhole was estimated between 7,700 and 23,200 m³ and the mean volume of sediment reached between 0.8 and 4.7 t per sinkhole.

Our results suggest that increasing the density of nature-based solutions from 2 to 8 per km² can reduce from 0.5 to 1.3 % the runoff volume and from 5 to 15 % the sediment load reaching the sinkholes. Our results also suggest that a complement of 20 m to 250 m of grassland upstream a sinkhole can reduce the sediment load from 5 to 13 % and the runoff from 0.5 to 1.5 %. Our results suggest that the localization of ploughed-up grasslands can have a significant impact on the generation of hydro-sedimentary transfers (up to 10 % more sediment discharge).

The results of this modeling exercise provided: (i) the first regional cartography of vulnerability of the 15,000 sinkholes to runoff and erosion, and (ii) local thresholds and valuable references to build and conduct efficient land and ground water degradation neutrality strategies with stakeholders.

How to cite: Maurié, A., Patault, E., Ledun, J., Deman, M., and Fournier, M.: Identification of thresholds to conduct efficient soils and water conservation strategies against erosion impacts: new insights from a modelling prospective in Normandy (France), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3799, https://doi.org/10.5194/egusphere-egu24-3799, 2024.

The middle reaches of the Yellow River (MYR) cover a significant portion of the Loess Plateau, rendering it among the most heavily impacted regions by soil erosion globally. Consequently, the MYR are characterized by high-intensity soil and water conservation measures, such as terracing and silt check dams, which exert a profound impact on soil erosion and sediment transport in this region. However, there is currently no accurate and clear assessment of sediment interception and sediment reduction contributions for large-scale and complex cascading silt check dams. This study enhances the Revised Universal Soil Loss Equation (RUSLE) model by coupling the processes of soil erosion, slope sediment production, and channel sediment transport. The study evaluates the slope erosion and sediment production through the combination of RUSLE and the Sediment Connectivity Index (IC). Additionally, it calculates the sediment interception and sediment output in the channel based on silt check dams sediment interception efficiency. Accurate classification of complex cascading silt check dams is crucial for assessing their sediment reduction contributions. The research employs a flow-based method for precise dam classification and incorporates the latest terracing distribution data to accurately assess the sediment reduction contributions of high-intensity engineering measures in the MYR. The research findings indicate: (1) The average annual soil erosion rate in the MYR from 1981 to 2017 is 13.32±31.94 t ha^-1 yr^-1, with moderate to severe soil erosion covering 15.1% of the area. (2) Over the past 40 years, there has been an overall decreasing trend in soil erosion in the MYR, with a significant reduction covering 8.65% of the area. Significant decreases in soil erosion began to appear after 2000, with an average annual soil erosion rate reduction of 0.34 t ha^-1 yr^-1. (3) Based on the cascading situation of silt check dams, the 2187 large silt check dams in the MYR are classified into 6 categories. Taking the initial siltation year as an example, for basins controlled by silt check dams, the sediment output rate without silt check dams is 3.444 t ha^-1 yr^-1, while with silt check dams, the sediment output rate is 0.468 t ha^-1 yr^-1, achieving a sediment reduction contribution of 86.4%. The upcoming tasks include: (1) investigating the interannual fluctuations in sediment reduction attributed to silt dams and validating the model; (2) formulating diverse scenario assumptions to evaluate the sediment reduction contributions from engineering measures and vegetation restoration. This study seeks to precisely evaluate the impact of high-intensity soil and water conservation measures on mitigating soil erosion and sediment transport in the MYR, offering insights for regional soil and water conservation practices and sustainable management.

How to cite: Huang, Y., Gao, G., and Wang, Y.: Effect of high intensity soil and water conservation engineering measures on soil erosion and sediment transport, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4527, https://doi.org/10.5194/egusphere-egu24-4527, 2024.

The Western Ghats are in the final stage of weathering. Hence, the Laterite, clay, and Saprolite layers can vary to depths greater than 50 meters. Thus, the Western Ghats have unique hillslope hydrology, with more than three-quarters of rainfall entering the subsurface flow, thus developing well-networked sub-surface conduits. These sub-surface conduits help maintain slope stability of the Shayadris' (Western Ghats) laterites, which are usually exposed to high-intensity rainfall for longer durations during the monsoon season. The slope failures and floods in 2018, 2019 and 2020 are due to Catchment Fragmentation leading to a disturbed hydrological cycle in both surface and subsurface levels. 

A unique observation showed that most of the landslides (mostly toe failures) were concentrated near the Harangi reservoir and had a valley stream connecting to the reservoir. During field observations in these slope failure sites, soil pipe was observed in the crest of the landslide scarp for most of the accessible locations. The slope failures could be due to backflows in the soil pipes during heavy rainfall and mismanagement of dam gates. Observations from local residents who had witnessed the slope fail gave an idea of backflows in these slopes, which they locally termed as JALASPHOTA – The burst of groundwater up these soil slopes. During field observations post-monsoon, streams were visible at the surface of the scarp through these soil pipes after the landslide. 
GSD of Lateritic soils of Kodagu is Clay, sandy clay, sand-silt clay, clayey sand, sand-silt-clay and clayey sand. A slow-moving landslide was observed on the highway connecting to Mangalore, where more clay content was observed. 
Juvenile and fully developed soil pipes were observed at the landslide scarp, and slopes with fully mature soil pipes were observed to have more runout distance. 
A few case studies of how catchment Fragmentation has disturbed the sub-surface hydrology, leading to slope failure, are discussed in this study. 

How to cite: Manjunath, K.: Field Observations of Soil Piping and associated disasters in the Western Ghats region of Karnataka (Kodagu district) , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4633, https://doi.org/10.5194/egusphere-egu24-4633, 2024.

Soil erosion represents a primary threat to soil systems with adverse implications for ecosystem services, crop production, potable water, and carbon storage. While numerous studies have quantified the spatial distribution of Above-Ground Biomass (AGB), soil erosion, and Soil Organic Carbon (SOC) in the Yangtze River Basin (YRB) in China, limited attention has been given to assessing the contributions of different land use types and especially crop types to AGB, soil erosion, and SOC. In most studies, cropland is taken as a land use class, while detailed crop types and rotation patterns, and their effect on soil erosion and SOC, vary significantly. In this study, we used the Metronamica model to generate a detailed crop rotation and distribution map across the YRB and subsequently employed the PESERA model to simulate the spatial distribution of AGB, soil erosion, and SOC on a monthly basis. PESERA model simulations indicate an average soil erosion rate across the entire YRB of 7.7 t/ha/yr, with erosion hotspots concentrated in the Sichuan Basin and the central-southern regions. The southwestern region and western Sichuan show elevated levels of AGB and SOC, while the eastern plains display lower levels. Erosion rates are lowest in areas designated as artificial land, pasture and grassland, whereas cropland and fruit trees experience the highest erosion rates. In terms of crop types, the highest erosion rates and lowest AGB are observed in fallow and potato cultivation, while the lowest erosion rates and highest AGB are found in rice-wheat rotation fields. To the best of our knowledge, this is the first study including detailed crop types and patterns into account while evaluating their effect on relatively large scale (i.e. YRB). These findings can help to develop sustainable soil management and (cropping) conservation strategies.

How to cite: Zhou, J., Baartman, J., Ning, Y., Carvalho Nunes, J., Ma, L., and Liu, X.: Quantifying above-ground biomass, SOC and erosion using a new detailed crop pattern map including double and triple cropping in the Yangtze River basin using the PESERA model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4784, https://doi.org/10.5194/egusphere-egu24-4784, 2024.

Soil erosion is one of the major processes of land degradation. Climate change, marked by alterations in the precipitation spatial and temporal patterns as well as rainfall amounts projected to increase, is expected to exacerbate soil erosion and loss of soil in the agricultural landscape. Understanding soil loss using physically-based water erosion prediction models and improving knowledge of soil erosion of agricultural lands under future climate change scenarios is critical to developing best management practices for the conservation of soil resources as well as to inform decision and policy makers. This study aims at investigating the impacts of future climate changes on soil erosion in the United States. By integrating up-to-date climate datasets this study characterized differences and current trends in precipitation with respect to climate change and applied a climate model ensemble based on the CMIP6 climate scenarios to predict the future climate. These data are downscaled with machine learning algorithms. It also estimates soil erosion in different soil-climate-agricultural management systems from predicted precipitation under future climate change scenarios using the Revised Universal Soil Loss Equation, Version 2 (RUSLE2). Research findings on the impacts of future climate change scenarios on soil erosion in agricultural landscapes will allow the development of climate-driven best management practices and conservation agriculture techniques as well as inform decision and policy makers to reduce soil loss, therefore protecting the limited soil and water resources, and contributing to a sustainable agricultural production and food security.

How to cite: Ghorbani, M., El Kadiri, R., Momm, H., Yoder, D., Dalmo, V., Bingner, R., Wells, R., Ferruzzi, G., and Darnault, C.: Predicting soil erosion under climate change: Using climate data to forecast future climate change scenarios and RUSLE2 modeling to estimate soil erosion on agricultural lands in the United States, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6779, https://doi.org/10.5194/egusphere-egu24-6779, 2024.

The Revised Universal Soil Loss Equation, Version 2 (RUSLE2) is the water erosion prediction tool for use by the USDA National Resources Conservation Service (NRCS) for all conservation planning in the United States. USDA NRCS utilizes the Integrated Erosion Tool (IET) that combines RUSLE2 with USDA data sets for soil, climate, and agricultural management. The Agricultural Research Service (ARS) is the USDA’s research agency charged with the development of the RUSLE2 model. RUSLE2 is an advanced computer model that estimates rill and interrill erosion by water, combining empirical and process-based science, for use on personal computers. This research aims at improving RUSLE2 science components, including the development of a web-based user interface for RUSLE2, for use by USDA NRCS. Advanced science components will be developed to quantify rainfall and land management effects on spatial and temporal variability of dynamic soil properties in agricultural watersheds in the United States, with emphasis on the assessment of soil erodibility and the risk of soil erosion under climate change. State-of-the-art technologies needed to measure, identify, and link dynamic soil erodibility to soil loss in the agricultural landscape, such as machine learning algorithms, remote sensing, and non-intrusive visualization and imaging technologies will provide advanced science components for RUSLE2. For the development of a web-based RUSLE2 modeling system, a new cloud based infrastructure is being deployed using the Amazon Web Services (AWS) platform, which will support online databases for climate, soil, and agricultural management data. A new database structure is being designed for RUSLE2, to support server based erosion calculations. AWS services will also provide web servers, spatial databases, geoprocessing capabilities, cooperative source code development and all compute and storage resources. These research findings and products will help understand how climate change and modern management practices impact soil erodibility dynamics. Improvements to RUSLE2 technology will lead to advances in determining soil loss across agricultural landscapes through improved physically based water erosion models. New web-based tools will provide best management practices for soil and water resources conservation under changing environments, contributing to sustainable agriculture and food security, while ensuring environmental health.

How to cite: Darnault, C., Ghorbani, M., Genc Kildirgici, G., Kethineedi, A., Ghimire, B., Calhoun, J., Momm, H., Yoder, D., Dalmo, V., Bingner, R., Wells, R., and Ferruzzi, G.: Revised Universal Soil Loss Equation, Version 2 (RUSLE2) Development: Advanced science components and web-based user interface for use in conservation planning, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6852, https://doi.org/10.5194/egusphere-egu24-6852, 2024.

Soil erosion causes severe on- and off-site effects, such as reductions in soil depth, eutrophication of water bodies, loss of organic matter, and clogging and smothering of riverine habitats. Attempts to assess water-induced soil erosion by water include modelling, measuring/monitoring, the use of tracers, and dating. All of these approaches have shown to have shortcomings (Parsons, 2019). The main objective of this research is to assess soil erosion in a small agricultural catchment (HOAL, Lower Austria) using modelling, OSL-dating, 137Cs and field measurements and to compare the gained results in the light of the shortcomings of each method. The study has been conducted in a small catchment (ca. 66 ha), located in the Northern foothills of the Eastern Alps in Austria (i.e. an area intensively agriculturally used since the Middle Ages). The catchment elevation ranges from 268 to 323 m a.s.l. and has a mean slope angle of 8 %. The lithology mainly consists of Tertiary marly to sandy deposits which are superimposed by Quaternary sediments (e.g. loess). The climate in this region is characterized as humid. The results of this study reveal significant – partly even dramatic - differences in soil erosion rates as derived from the different assessment methods. Details as well as a critical method comparison will be provided at the EGU General Assembly 2024.

References:
Parsons, A. J. (2019). How reliable are our methods for estimating soil erosion by water? Science of the Total Environment, 676, 215-221.

How to cite: Pöppl, R., Renschler, C., Abatti, B., Asimus, N., Kraushaar, S., Strauss, P., and Fuchs, M.: Assessing soil erosion in a small agricultural catchment in Austria using OSL-dating, modelling, 137Cs and field measurements: a critical comparison, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9422, https://doi.org/10.5194/egusphere-egu24-9422, 2024.

A healthy soil supports life on Earth through maintaining ecosystems that provide food, feed and fibre whilst supporting Earth system functions such as waste recycling, climate, flood, and water regulation. The intensification of anthropogenic activities and climate challenges pose serious threats to soil health (Hassani et al., 2021), exacerbating the processes of soil degradation that are putting at risk soil management, biodiversity, and food security.

This study thus aims at enhancing our understanding of the state and changes of soils by combining machine learning methods with a comprehensive series of climate and environmental variables. We employ machine learning methods to analyze the relationships between soil health indicators and a wide range of climatic parameters, and chemical, physical, and biological soil attributes in Europe. Capitalizing on the LUCAS (Land Use/Cover Area frame statistical Survey) topsoil database (2009-2018) and digital soil mapping techniques, our preliminary results highlight the regions across Europe showing consistent decline in soil nutrients and carbon content, signaling potential risks of soil degradation. The proposed framework enables us to understand, document and respond to soil changes in ecosystems under different land management and climate scenarios. This contributes to devising necessary action plans for sustainable soil management and preservation.

This research is part of the project AI4SoilHealth (Accelerating collection and use of soil health information using AI technology to support the Soil Deal for Europe and EU Soil Observatory) funded Horizon Europe (Grant No. 101086179).

Reference

Hassani, A., Azapagic, A., Shokri, N. (2021). Global Predictions of Primary Soil Salinization Under Changing Climate in the 21st Century, Nat. Commun., 12, 6663. https://doi.org/10.1038/s41467-021-26907-3.

How to cite: H. Afshar, M., Hassani, A., Aminzadeh, M., Borrelli, P., Panagos, P., Robinson, D. A., and Shokri, N.: AI-driven insights into soil health and soil degradation in Europe in the face of climate and anthropogenic challenges, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9512, https://doi.org/10.5194/egusphere-egu24-9512, 2024.

Erosion is one of the most important threats for soil. Over the long term, soil erosion can have serious on-site (e.g. decrease in agricultural yield) and off-site impacts in morphogenic zones but also important off-site (e.g. mudflow) impacts in plains. Much more efforts have been devoted to study erosion processes in morphogenic zones that have naturally higher erosion rates than plains. However, the intensification of agriculture during the latter part of the 20^th century significantly altered landscapes and increased hydrosedimentary connectivity in agricultural plains. The off-site consequences are numerous: mudflows, increasement a river turbidity, siltation in rivers, transfers of pollutants associated with sediments, etc. Generally, in temperate climate, the main source of sediments is the surface runoff that occurs on fields during winter or spring but in lowland areas the subsurface drainage network is a supplementary pathway for runoff and sediments. The few studies that have quantified erosion over a complete hydrological year show subsurface drainage contribution to erosion is very variable. It is still difficult to propose a hierarchy and to quantify factors affecting soil erosion by subsurface drainage. In this study, suspended solids (SS) concentration and water flow of a lowland field have been measured during two consecutive years both at the outlets of surface and subsurface drainage networks. SS yield was 0.49 t ha^-1 and 1.08 t ha^-1 in 2019–2020 and 2020–2021, respectively. During 2019–2020 and 2020–2021, subsurface drainage contribution to the total runoff was 46% and 21%, respectively and its contribution to SS yield was 9% and 11%, respectively. High temporal resolution measurements of SS concentrations showed the suspended sediment concentration increased at the outlet of both surface and subsurface drains from the first to the second year. These variations and the increase of surface runoff rate suggest a shift in water and sediment connectivity at the field scale. Based on water tracing, water balance and analysis of rainfall characteristics, the main driver is likely cropping practices. This study confirms the majority of sediment exports occurs during a short period, cause by only few runoff event of winter and adds a new quantification of hydrosedimentary fluxes in a surface and subsurface drained field separating surface and subsurface drainage contribution. It also shows that in hydromorphic drained areas, despite the very slight slope, surface runoff can represent the major pathway for soil erosion. Adapted soil tillage practices must be developed to preserve the agricultural production capacity of the fields, maintaining water exports, while simultaneously reducing sediment exports.

How to cite: Gaillot, A., Cerdan, O., Salvador-Blanes, S., Vanhooydonck, P., Grangeon, T., Desmet, M., and Delbart, C.: Hydrosedimentary functioning of a lowland field with both surface and subsurface drainage., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10802, https://doi.org/10.5194/egusphere-egu24-10802, 2024.

The study of the sustainable strategies at regional level complies with the current European Green deal to monitor soil compaction. However, recent studies showed that the implementation of sustainable practices by farmers that are useful for an ecological transition can be slow down by development and technology transfer capacity and or an attitude of resistance of farmers themselves to innovations.

In the context of soil compaction in grasslands, we studied the influence of different management strategies (use of cattle and machinery) and the farmers’ perception of soil compaction. The studied bio-physical indicators in the top soil were organic carbon, plant indicators, bulk density, soil texture, plant indicators, infiltration capacity, water repellence, water content and electrical conductivity at the surface level of permanent grasslands in a total of 16 grasslands in the time period 2022-24 within Görtschitztal and Magdalensberg in south Austria (Carinthia).

First results showed correlation between the use of cattle and number of entries in the field with heavy machinery and the increase of the bulk density, though always within low levels of compaction and at the surface. We also found cases of mismatch perception of soil compaction, which may hinder sustainable practices in the future. The results of this study may serve to increase understanding about the theoretical factors influencing the farmer’s perception of soil compaction problems, providing a valuable addition to the available literature. In terms of policy implications, a clear picture of the factors underlying the dynamics of farmer’s perception can be useful in the future to better targeting policy measures tailored to encourage sustainable practices and innovations in the agricultural sector. We show possible directions affecting perceptions at farmer-based level.

How to cite: Puff, M., Garcia-Santos, G., and Bohner, A.: Study about perception of soil compaction in grasslands: what can be learnt to foster sustainability and policy intervention?, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10943, https://doi.org/10.5194/egusphere-egu24-10943, 2024.

Soil erosion is a significant process in the loss of soil/land resources, degradation and desertification. Traditionally, wind and water erosions have been studied and modelled separately. A quantitative sediment flux measure from a specific soil due to both water and wind erosion is lacking. The study aimed to drive such erosion rates in a semi-arid loess soil that is subjected to both forces of erosion. Soil samples from top-and sub-layers of the soil were analyzed for physical and chemical properties, including characteristics of soil aggregation. We performed targeted laboratory experiments using a boundary layer wind-tunnel for wind erosion and rainfall simulator for water erosion. Rates of sediment flux that were calculated for the topsoil and the subsoil revealed an opposite trend between water and wind erosion. This indicates that soil erodibility strongly depends on the erosional force applied rather than a certain soil property. The study conducted in a semi-arid region and may serve as a case study under climate change scenarios, in which more (non-arid) regions will be subjected to increase soil erosion.    

How to cite: Katra, I., Ben-Hur, M., and Tanner, S.: Comparison of soil erosion rates by wind and water in a semi-arid loess soil , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12285, https://doi.org/10.5194/egusphere-egu24-12285, 2024.

The impact of land degradation on the environment is multidimensional and is fundamentally influenced by various land degradation processes, which usually interact spatially in a convergent manner. However, the spatial pattern of multiple converging (co-occurring) land degradation pathways remains largely unexplored in Europe. To address the synergistic (convergent) nature of land degradation, in this work we modelled and mapped the spatial pattern of twelve interacting processes in agricultural/arable environments of Europe. Therefore, using state-of-the-art and large-scale datasets that were modelled via appropriate GIS (Geographic Information System) techniques, we performed an unprecedented investigation on land multi-degradation in 40 European countries. Essentially, we found that up to 27%, 35% and 22% of pan-European agricultural/arable landscapes are synergistically affected by one, two and three land degradation processes, while 10–11% of continental agricultural/arable environments are cumulatively threatened by four and at least five co-occurring processes. Our multi-process framework can be a valuable scientific tool for complex modelling of land degradation, but also for applying various agricultural, climate or sustainable development policies at European level.

How to cite: Pravalie, R., Borrelli, P., Panagos, P., Niculiță, M., Bandoc, G., Patriche, C., and Roșca, B.: Towards a unifying approach of land degradation in Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12401, https://doi.org/10.5194/egusphere-egu24-12401, 2024.

Soil erosion represents a crucial environmental issue worldwide that threatens land, freshwater, and oceans. Subsurface erosion by soil piping occurs in almost all climatic zones of the world and in various soil types. Its occurrence changes the conditions for controlling measures to reduce soil degradation. However, it remains one of the most overlooked soil erosion processes, and its global and regional recognition is poorly documented. This project aims to construct a piping erosion susceptibility map of Europe in order to identify locations affected by this process, and where specific erosion control measures should be taken. Firstly, we compiled a database of soil piping-related features, i.e. pipe roof collapses (PCs) and pipe outlets in the European Union and the UK that consists of 6841 locations having piping-related features (6171 PCs and 670 outlets), among which the location of 88% features is known at a resolution of 25 m. Then, this database is used to model the susceptibility of soils to piping erosion at the European scale. We applied the logistic regression model using the scikit-learn library in Python. The following environmental factors are tested: topography (such as slope and height difference), pedology (content of silt, clay, sand, and coarse fragments), land use and land cover, and climate (such as effective precipitation). Our preliminary result clearly shows that it is feasible to accurately identify the European hotspots susceptible to piping erosion, based on a combination of land use, topographic and soil variables (AUC >0.75). The presented map is an important step towards incorporating subsurface soil erosion into regional and global soil erosion models.

This research is part of a project “Building excellence in research of human-environmental systems with geospatial and Earth observation technologies” funded by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 952327. The research has also been supported by a grant from the Faculty of Geography and Geology under the Strategic Programme Excellence Initiative at Jagiellonian University.

How to cite: Bernatek-Jakiel, A., Vanmaercke, M., Poesen, J., Biernacka, A., Borrelli, P., Derii, A., Hałys, J., Holden, J., Jakab, G., Jakiel, M., Panagos, P., Piątek, D., Regensburg, T. H., Rodzik, J., Nadal-Romero, E., Stolarczyk, M., Verachtert, E., Wacławczyk, P., and Zgłobicki, W.: A piping erosion susceptibility map of Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12976, https://doi.org/10.5194/egusphere-egu24-12976, 2024.

Soil resources in East African agro-pastoral lands are being rapidly depleted by erosion, threatening food, water and livelihood security. Here we explore the utility of innovation in portable gamma sensors to rapidly assess soil health via proxy measurement of soil organic matter (SOM) providing visual information that enables local communities to take action to mitigate land degradation before it reaches a critical tipping point.

This study is grounded in the outcomes of an integrated, interdisciplinary approach to support co-design of land management policy tailored to the needs of specific communities and places. The work has shown that limitations to delivering socially acceptable and environmentally desirable solutions can be addressed by (1) closing fundamental gaps between the evidence bases of different disciplines and indigenous knowledge and (2) addressing, through participatory action, the implementation gap between science-based recommendations, policy makers and practitioners. Key adaptations implemented in the study region include new bylaws to enforce altered grazing regimes, grassland recovery and tree planting.

Against this context, we report a first trial of a portable gamma spectrometer to rapidly assess spatial variability in soil health using total and radionuclide-specific gamma emissions from naturally occurring radioisotopes as a proxy for soil organic matter. A Medusa MS-700 portable gamma spectrometer was deployed on foot across a landscape of known variability in soil health status encompassing a spectrum of impact from severely gullied soil/subsoil, heavily grazed surface soil, recovered grazed soil (ca 3 years exclusion of livestock) and conservation agriculture plots. In-situ field results showed a clear gradient in raw total gamma count rate with sample areas in each zone at 1200 ± 100, 980 ± 70, 814 ± 60 and 720 ± 60 counts per second across the above four areas respectively.  Correlations between radioisotope-specific gamma spectrometer data and organic matter (range 15 ± 2 to 30 ± 3 g kg^-1 from degraded land to conservation agriculture) were evaluated to explore the dominant control on sensor response. Further comparisons are made to major and minor element geochemistry. Feedback from local Maasai community members who participated in the research further underpins the value of the sensor as a qualitative assessment tool e.g. using visual colour coding in the live data feed in the field. Quantitative comparison of sensor and laboratory data will permit development of protocols for airborne (drone) gamma spectrometry that offers community scale evaluation of grazing pressure on soil health to inform livestock future exclusion policy in common land prone to soil erosion.

How to cite: Blake, W., Amasi, A., Kelly, C., Lewin, S., Mkilema, F., Msale, F., Mtei, K., Munishi, L., Nasseri, M., Ndakidemi, P., and Taylor, A.: Novel use of portable gamma sensors to rapidly assess soil status and recovery in degraded East African agro-pastoral land, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13351, https://doi.org/10.5194/egusphere-egu24-13351, 2024.

To appropriately place soil conservation measures, locating the most vulnerable areas prone to soil erosion is required. Available tools to locate vulnerable areas are tedious to use and time-consuming, and most water erosion estimations are based on empirical models with limited applicability. The present study takes advantage of two large-scale soil and water conservation tools available for the Midwest U.S.: the Daily Erosion Project (DEP) and the Agricultural Conservation Planning Framework (ACPF).

In this study, we will showcase a recently developed large scale modeling approach implemented in the Midwest U.S. that currently downscales DEP from Hydrologic Unit Code (HUC) 12 (~90 km²) average estimation of hillslope runoff and soil loss into a much finer resolution, a field and pixel scale. The DEP uses the Water Erosion Prediction Project (WEPP) and simulates hundreds of thousands of hillslopes across the Midwest, covering the wide range of factors including topography, climate, soils and land use and management.

This presentation will introduce the newly developed quantitative soil erosion assessment tool (named OFEtool - Overland Flow Element tool) that uses geographic information systems (GIS) and a physical-based model with real climate data (DEP). The OFEtool analyzes a watershed and groups areas with similar attributes, such as slope, soil type, land use, and management practices (information provided by the ACPF). Following watershed analysis, the tool uses DEP simulations to obtain average hillslope soil erosion or deposition rates for these grouped characteristics. Finally, it associates and assigns these rates to the respective areas within the watershed.

The current version of the tool is used by the ACPF to locate the most vulnerable fields across the watershed for conservation planning scenarios to prioritize interventions in fields and specific areas with the highest erosion rates. The applicability of the tool will be shown for the state of Iowa (approximately 145,746 square kilometers). Preliminary results corroborate spatial variability of soil erosion within watersheds and Major Land Resource Areas (MLRA). The presentation will also provide new insights into the main factors governing soil erosion in Iowa (climate, soils, topography, land use and management).

References

Gelder, B., Sklenar, T., James, D., Herzmann, D., Cruse, R., Gesch, K., & Laflen, J. (2018). The Daily Erosion Project – daily estimates of water runoff, soil detachment, and erosion. Earth Surface Processes and Landforms, 43(5), 1105–1117. https://doi.org/10.1002/esp.4286

Daily Erosion Project. (n.d.). Retrieved January 9, 2024, from https://www.dailyerosion.org/

Tomer, M. D., Porter, S. A., James, D. E., Boomer, K. M. B., Kostel, J. A., & McLellan, E. (2013). Combining precision conservation technologies into a flexible framework to facilitate agricultural watershed planning. Journal of Soil and Water Conservation, 68(5). https://doi.org/10.2489/jswc.68.5.113

Agricultural Conservation Planning Framework. (n.d.). Retrieved January 9, 2024, from https://acpf4watersheds.org/

How to cite: Luquin, E., Gelder, B., Herzmann, D., Zimmerman, E., James, D., Karnish, K., and Cruse, R.: A GIS-modeling strategy to locate vulnerable agricultural fields and prioritize conservation efforts across the Midwest United states., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13949, https://doi.org/10.5194/egusphere-egu24-13949, 2024.

The mechanism of the interrill erosion process is still unclear under complex conditions. Spatio-temporal variations of the near-surface hydraulic gradient are a common occurrence; however, few attempts have been made to characterize the near-surface hydraulic gradient for erosion prediction. Therefore, the objective of this study is to determine the influence of exogenic erosional forces (rainfall, overland flow, and seepage) on interrill erosion processes by considering the impact of the near-surface hydraulic gradient. Five near-surface hydraulic gradients (70% of field capacity, field capacity, saturated, artesian seepage at 20 cm and 40 cm of the hydrostatic pressure head) were applied in clay loam soil at two representative slope gradients of 8.75% and 17.63% under three rainfall intensities of 30, 60, and 90 mm h^-1. The results showed that the near-surface hydraulic gradient was the dominant factor in the interrill erosion process in addition to rainfall intensity (I), runoff (Q), and slope gradient (S). There was a significant improvement in the prediction accuracy of the interrill erosion rate when the factor of near-surface hydraulic gradient was introduced into the interrill erosion prediction equation based on the Water Erosion Prediction Project (WEPP) concept. The R² and NSE values were 22.36% to 210.00% higher than those of existing empirical equations (main parameters: I, I&S, I&Q, I&S&Q). The correlation matrix results indicated that the flow velocity was a key hydraulic parameter for predicting the interrill erosion rate. The interrill erosion rate was predicted well by a simple power function of the flow velocity, although this relationship lacks clear physical meaning. We also found that the interrill erosion rate increased as a power function with the runoff depth, rainfall intensity, hydrostatic pressure head and slope gradient. Considering the integrated effect of the exogenic erosional dynamics on the interrill erosion, a power function that included the physical description of the hydrodynamic parameters, rainfall intensity and hydrostatic pressure head was used to predict the interrill erosion rate. The results of this research provide new insights into developing process-based and mechanistic models for interrill erosion processes.

How to cite: Wang, B., Wang, Y., and Wang, C.: Improved interrill erosion prediction by considering the impact of the near-surface , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14123, https://doi.org/10.5194/egusphere-egu24-14123, 2024.

The impact of near-surface hydraulic gradients on interrill erosion is still obscure. The objective of this study is to distinguish the dominant interrill erosion process in areas impacted by near-surface hydraulic gradients. A series of rainfall simulations were conducted on a clay loam soil subjected to near-surface hydraulic gradients that shifted from drainage/saturation conditions to seepage conditions under three rainfall intensities (30, 60 and 90 mm hr⁻¹) and two slope gradients (5 and 10). The results showed significant differences in soil loss between all the treatments. The sediment concentrations for seepage conditions were 0.57 to 7.02 times greater than those for drainage conditions. The correlation analysis indicated that the near-surface hydraulic gradient was a governing factor affecting interrill erosion. The critical flow rate was larger than 90 mm hr⁻¹, suggesting that thin sheet flow does not have sufficient power to detach soil particles without raindrop impact. Furthermore, the detachment rates by raindrop impact were 1.12 to 4.60 times greater for seepage conditions than for drainage conditions. As the near-surface hydraulic gradient shifted from drainage conditions to seepage conditions, it transitioned from transport-limited to detachment-limited, and the contribution of interrill erosion to overall erosion increased from 20.19 to 75.30%. The critical point of dominant interrill erosion process transition existed between saturation (SA) and artesian seepage in 20 cm of hydrostatic pressure head (SP20). The results emphasize the importance of the near-surface hydraulic gradients’ impact on the interrill erosion process. Further investigations need to be verified in different soil types, steeper slopes and natural storms.

How to cite: Wang, Y., Wang, B., Wang, C., and Wang, Y.: Impact of near-surface hydraulic gradient on the interrillerosion process, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14241, https://doi.org/10.5194/egusphere-egu24-14241, 2024.

Deforestation for cropland expansion in the sloping landscapes along the East African Rift system causes severe soil erosion and thus the loss of fertile, organic rich topsoil. However, the varying effect of land degradation in the region on soils developed from different parent material - which may influence soil fertility and carbon stabilization - are still largely unknown. To examine these factors, we compared soil organic carbon (SOC) and soil fertility indicators in undisturbed forest topsoils with cropland hillslope topsoils along a chronosequence after deforestation (2–7, 10–20, 20–40, > 60 years of cropping, land abandonment) on mafic (South Kivu, Democratic Republic of Congo) and felsic parent material (western Uganda). From previous studies, we expected higher soil fertility and SOC contents and therefore slower degradation on mafic soils due to the higher amounts of clay and pedogenic metal phases which stabilize SOM and thus further maintain soil fertility.
However, we found similar SOC contents on both parent materials and a consistent decrease with time after deforestation. SOC values were significantly lower in soils that were cleared more than 60 years ago, compared to cropland which was cleared 2–7 years ago and nearby undisturbed forest topsoils (0–10 cm soil depth). While the effective cation exchange capacity (ECEC) positively correlated with SOC in soils on felsic parent material, this was not observed in soils with mafic parent material, where it correlated with mineralogical proxies (total reserves in bases). In both regions, SOC did not correlate with clay content. Mid-Holocene carbonate volcanism appears to have offset soil degradation in the felsic region, contributing to higher pH and ECEC and impeding land abandonment due to the maintenance of acceptable soil fertility levels. Surprisingly, abandoned cropland sites in the mafic region still had an average SOC content of 14–29 g kg^-1 in topsoils, likely due to strong fixation of SOC with reactive metal phases; however, they were characterized by extremely low pH values and high Al³⁺ mobility, combined with low available nutrient status.
Our results emphasize that soil fertility and carbon stabilization are reliant on the mineral composition of the underlying parent material, even in deeply weathered soils of the humid tropics. Soil organic matter in degraded tropical cropland soils does not appear to be a reliable indicator of soil fertility.

How to cite: Summerauer, L., Bamba, F., Akoraebirungi, B., Wobusobozi, A., Drake, T. W., Kabaseke, C., Muhindo, D., Cizungu Ntaboba, L., Ramirez-Lopez, L., Six, J., Wasner, D., and Doetterl, S.: Parent material modulated effects of soil degradation on fertility and organic carbon of tropical cropland soils in Eastern Africa, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15313, https://doi.org/10.5194/egusphere-egu24-15313, 2024.

Olive tree plantations, an ancient and traditional crop in the Mediterranean region, have become erosion-prone due to their soil management and location. Many olive groves are often planted on slopes, where soil management often keeps the soil bare by conventional tillage and/or herbicide use. Further, the natural conditions of the region as long drought periods followed by intensive rainfall episodes, intensify the susceptibility to erosion. As a result of these factors, soil erosion has become a major threat to the sustainability of olive cultivation in southern Spain.

On-site soil erosion measurements through conventional methods usually do not exceed one decade and present several discrepancies among them and with modelling outcomes. Here, we aim to use fallout radionuclide (FRN) inventories (¹³⁷Cs, ^239+240Pu) together with 3D reconstruction of surface levels to estimate soil erosion rates at appropriate temporal and spatial scales for the last 55-60 years and/or from the beginning of tree plantation. Twelve soil cores up to 40 cm depth were taken across olive groves and in identified reference sites, and the model MODERN (Modelling Deposition and Erosion rates with RadioNuclides) (Arata et al., 2016) was used to estimate soil erosion rates from 1960. For the geomorphological reconstruction, manual measurements were taken to recreate the historical soil surface using the germination point in the olive trees as a reference point to the current soil surface. Both methods allowed us to estimate and understand past erosion processes and possible long-term trends.

The radiochemical analysis content of ¹³⁷Cs, ^239+240Pu inventories and its correlation with a geomorphological reconstruction on selected olive tree fields under different soil management in southern Spain will be presented.

Arata, L., Meusburger, K., Frenkel, E., A’Campo-Neuen, A., Iurian, A.-R., Ketterer, M. E., Mabit, L., & Alewell, C. (2016). Modelling Deposition and Erosion rates with RadioNuclides (MODERN) – Part 1: A new conversion model to derive soil redistribution rates from inventories of fallout radionuclides. Journal of Environmental Radioactivity, 162–163, 45–55. https://doi.org/10.1016/j.jenvrad.2016.05.008

How to cite: Moreno Romero, G., Alewell, C., and Borrelli, P.: Land degradation due to soil erosion in the Mediterranean olive groves: A comparison of 137Cs, 239+240Pu radionuclides and 3D reconstruction of surface levels, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16310, https://doi.org/10.5194/egusphere-egu24-16310, 2024.

Adequately assessing the export of sediments and dissolved solids at the outlet of representative watersheds provides extremely interesting information on the behavior of these watersheds, with important environmental and management implications. To this end, the Government of Navarre (Spain) began to implement in 1995 a network of five watersheds representative of different agricultural and forestry conditions in Navarre. La Tejería and Latxaga watersheds, occupy about 200 ha each in a humid sub-Mediterranean climate and are almost completely cultivated with winter grain. Oskotz Principal watershed comprises 1,688 ha under sub-Atlantic climate, most of it covered with forest (61%) whereas the remaining area is covered by pastures and arable land. Within the Oskotz watershed, a 434 ha sub-watershed almost fully covered with forest namely Oskotz Forested, is also monitored. Landazuria watershed covers an area of 480 ha being its climate dry Mediterranean. Over 88% of the watershed area is cultivated, with about 60% of the total cultivated area under pressurized irrigation systems. The rest of the cultivated surface is rainfed agriculture. Average anual suspended sediment concentration are 182 mg/L for La Tejería, and 38, 12, 12, and 30 (median) for Latxaga, Oskotz Principal, Oskotz Forested and Landazuria, respectively. Average anual exported sediment are 4.3 ± 3.7, 1.4 ± 1.7, 1.2 ± 0.9, 0.7 ± 0.6 and 0.3 ± 0.5 Mg/ha for the same watersheds. The average annual export of dissolved solids for the same watersheds is 1.1, 1.1, 2.2, 1.9 and 2.2 Mg/ha.

As for 2010, the 5,500 ha Cemborain river basin (583 mm of precipitation at its outlet) has been incorporated into the monitoring, with the intention of understanding the behavior of a much larger and more complex basin. The dominant land uses are forestry and scrubland (70% of the basin), while cultivated soils cover about 25% of the surface area. The data corresponding to this basin, still very preliminary, are presented for the first time and contextualized in this work. The mean suspended sediment concentrations in Cemboráin are 120 mg/l, with a great temporal variability, increased by suspiciously high values in summer, possibly due to the presence in the samples of various residues instead of sediments. The average sediment export at the outlet of the basin is 3 kg/ha/day in the winter months (January to March), which is 5.0 and 2.8 times lower than those found in La Tejería and Latxaga watersheds (the most similar in terms of climate and soils) for the same period. The average export of dissolved solids was 2.2 kg/ha/day, a figure 3.7 and 4.6 times lower than those found in La Tejería and Latxaga watersheds, respectively. Practically all exports in Cemborain have occurred between December and March. The low sediment export figures are consistent with what is to be expected given that the soil is much more protected than in the cereal basins.

How to cite: Percaz, M., Barberena, I., Campo-Bescós, M. A., Giménez, R., and Casalí, J.: Improving our understanding of sediment and dissolved solids export in Mediterranean croplands: comparative analysis of the response of watersheds with contrasting characteristics, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16461, https://doi.org/10.5194/egusphere-egu24-16461, 2024.

Badlands landscapes are usually subjected to high erosion rates and soil degradation, representing the main source of fine sediments in some catchments, especially in Mediterranean regions. High erosion rates imply high sediment transfer downstream, with associated environmental and management implications. Coupling between hillslope and channel processes has been proved as a critical factor in the evolution of badlands landscapes. This work examines the hillslope-channel coupling and geomorphic processes in a sub-humid badlands landscape using a 10-year dataset of high-resolution topography in relation with hydro-meteorological drivers. Study catchment (0.45 km2) is located in the Central Southern Pyrenees. Topographic datasets were obtained through multi-temporal surveys (i.e., seasonally and annually) carried out by means of Terrestrial Laser Scanner (TLS) and Structure from Motion (SfM) photogrammetry. Hydrologic records were obtained from a gauging station located at the catchment outlet while rainfall was recorded in three tipping-bucket distributed along the study area. The study analyses the relationships between the hillslope erosion and the main-channel incision processes, and how they interact to shape the badlands landscape over time in relation with the hydro-meteorological registers. The study also highlights the importance of high-resolution topography in understanding erosion and the complex interactions between hillslope and channel processes, and the need for continued monitoring to better understand the long-term geomorphic and hydrological processes in these areas.

This work is supported by the MOUNTWATER (TED2021-131982B-I00) research project funded by the MICINN-Plan de Recuperación, Transformación y Resiliencia and the EU-NextGenerationEU.

How to cite: Llena, M., Revuelto, J., Gómez-Gutiérrez, Á., López-Moreno, J. I., Errea, M. P., Alonso-González, E., and Nadal-Romero, E.: Hillslope-channel coupling and geomorphic processes in a sub-humid badlands landscape: Evidence from 10 years of high-spatial resolution topography and hydrologic record, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17090, https://doi.org/10.5194/egusphere-egu24-17090, 2024.

Soil erosion, in its various forms, has been identified as one of the major soil threats worldwide because it is one of the most significant forms of land degradation (soil truncation, loss of fertility, slope instability, etc.) and loss of soil- based ecosystem services; causing irreversible effects on the poorly renewable soil resource. The Revised Universal Soil Loss Equation (RUSLE) is one of the most widespread adopted empirical model approaches for assessing long-term average soil loss rate by water erosion. The assessed soil loss rate is an indicator that describes (or measures) the state of the soil erosion in a specific area (field, catchment, region, country) which we are interested in. The quality of this indicator relies on the scale which it represents and its required data. Many European countries, such as Italy, do not have harmonised national soil erosion databases at the different scales required by decision makers (regional, provincial, local) and national scale assessments have been carried out using EU data (JRC 2015, LUCAS 2018). However, national scale assessments are not often coherent with the more detailed information available at regional scale for some Italian regions in which RUSLE based potential soil erosion maps have been produced. Although it would be predictable, it is of particular interest to assess how reliable a national scale assessment can be in providing information on the state of soil erosion at a regional scale. A regional soil database is available for the Tuscany region (IT) and it is suitable for soil erosion assessment at regional scale. In this context, within the framework of the EJP SOIL project SERENA, the study was aimed at comparing three RUSLE applications carried out i) at regional scale by means of the available regional soil/climate/digital terrain model data; ii) at national scale by means of the same datasets upscaled at country level; iii) at national scale based on datasets actually available for all the Italian territory.

This scale effect is likely due to 2 components. First, the spatial density and quality of the observations needed to estimate the RUSLE factors. To this regard, soil and climate data quality and availability are usually higher for small territories than for the whole national territory. Secondly, the reference scale adopted for the aggregation and spatialization of the data, which is particularly important for the LS factor. These two reasons lead to a lower reliability of the RUSLE applications at national scale as compared to a regional one. The assessment at the regional scale of the soil loss rate using the Tuscany Region dataset was used as reference to evaluate the results obtained with the other two datasets at the same regional scale. Such comparisons were made using both the differences among the erosion maps, and through statistical indices that measure the deviations between the reference map and the other spatial products.

How to cite: Medina-Roldán, E., Buttafuoco, G., Gardin, L., Lorenzetti, R., and Ungaro, F.: Comparison of national and regional assessments of soil loss rate by water erosion: an application to the Tuscany region (Italy)., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17115, https://doi.org/10.5194/egusphere-egu24-17115, 2024.

To address the challenge of soil degradation among different land uses, development of precise indicators that accurately reflect the current state of soil health is crucial. Soil structural attributes, such as the volume of percolating pores and the connectivity of the pore network are inextricably linked to processes such as nutrient dynamics, carbon cycling, root penetration, biological activity, and rainfall partitioning. Hence, they play a significant role in determining the soil susceptibility to erosion and offer great potential as soil health indicators. These attributes are directly reflected in the hydraulic properties of the soil, particularly in its capacity for water infiltration and retention. Notably, high rates of infiltration and drainage are associated with the presence of well-connected macropores. However, these structural attributes typically have to be quantified using costly and time-consuming imaging methods, while obtaining accurate estimates in lab and field experiments has proven challenging. Our multilevel approach is designed to link directly measured structural attributes (macropore volume and connectivity) to standard field or lab measurements.

More specifically, macropore volume and connectivity were quantified using X-ray imaging across diverse land use types, including arable land, grassland, and forest. Structural characteristics were then correlated with key hydraulic properties, such as water retention and both saturated and unsaturated hydraulic conductivity, measured using the Hyprop system. We further compared the imaged and measured hydraulic properties with predictions from the European soil texture-based pedotransfer function EUPTF, to contrast texture- and structure-related soil hydraulic properties. As an additional exploratory angle, we related mid-infrared (MIR) spectral reflectance to our previously obtained hydraulic property data, to evaluate if MIR could serve as a less laborious alternative to traditional lab-based analyses. Finally, to develop applicable user-friendly and sensitive indicators, we correlated our findings with the classifications from in-situ Visual Evaluation of Soil Structure (VESS) and infiltration experiments.

Preliminary results of X-ray CT data and Hyprop measurements revealed significant differences in the volumetric fraction and drainage capacity of macropores as well as in the saturated hydraulic conductivity between arable land, grassland, and forest. Forest soil showed the largest drainage capacity of macropores, but also the largest variability between samples. Despite exhibiting similar pore size distributions, arable land samples showed, as a result of tillage, larger pore connectivity than grassland. Larger connectivity did, interestingly, not result in larger hydraulic conductivity of macropores. 

Our novel multilevel approach reveals clear distinction of land use regarding the complex interplay between soil structural continuity, soil texture, and hydraulic behavior. Such knowledge is crucial in formulating sensitive, quantifiable, and scalable indicators for soil health evaluation and management. These indicators are instrumental for creating more accurate models, for designing sensitive monitoring networks and ultimately advancing sustainable practices in agriculture, forestry, and environmental conservation.

How to cite: Schmücker, N., Lehmann, P., Duddek, P., Kirchgessner, N., Carminati, A., and Nussbaum, M.: Bridging the Gap: A Multilevel Approach to Soil Health Assessment across Various Land Uses, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18768, https://doi.org/10.5194/egusphere-egu24-18768, 2024.

The Government of Navarre (Spain) began to implement in 1995 a network of five watersheds representative of different agricultural and forestry conditions in Navarre. In this paper we focus on 4 of them. La Tejería and Latxaga watersheds occupy about 200 ha in a humid sub-Mediterranean climate and are almost completely cultivated with winter grain. Oskotz Principal watershed comprises 1,688 ha under sub-Atlantic climate, most of it covered with forest (61%) whereas the remaining area is covered by pastures and arable land. Within the Oskotz watershed, a 434 ha sub-watershed almost fully covered with forest namely Oskotz Forested, is also monitored.

Ten-minute data on flow (Q), water turbidity (T) and the most important meteorological variables are recorded in all the watersheds. Samples are collected daily to determine the concentration of suspended sediments (SSC) and various dissolved substances.  In addition, and since 2006, during particularly heavy rainfall-runoff events, another parallel sampling is activated to determine the sedimentogram in much greater detail. The number of samples taken depends on the Q and T variations detected.

For this study, events have been selected that meet the following requirements: i) there is a clear raising flow phase and a clear decreasing flow phase; ii) at least six samples have been collected and processed throughout the event for SSC determination; iii) the linear regression between Q and T yields a value of r2> 0.75. From this regression equation it is possible to obtain a very detailed sedimentogram (tenminute basis).

A total of 30 events meet the requirements, 7 in La Tejería, 9 in Latxaga, 5 in Oskotz Forestal and 9 in Oskotz Principal.  Hysteresis is observed in all of them. In the cereal watersheds, 75% of the hysteresis curves are of hourly character, that is, with the peak of the sedimentogram located in the rising part of the hydrograph. In these watersheds, the remaining 25% correspond to curves with a complex structure linked to the occurrence of several flow peaks in the same event, which will require further study. In the Oskotz Forestal watershed 3 of the curves are clockwise and two are "eight" shaped, while in Oskotz Forestal 8 of the nine curves are clockwise and one is "eight" shaped.

These preliminary results suggest that in the cereal watersheds the main sediment sources are in the proximity to the watershed outlet, probably in the same channels. In the Oskotz watersheds, the main sources are also mostly located in the vicinity of the outlet, although occasionally other sources far from the outlet are also activated, mainly in the forest watershed.

How to cite: Casali, J., Otazu, M., Barberena, I., Campo-Bescós, M. A., and Giménez, R.: Analysis of high-resolution flow vs. suspended sediment concentration curves to determine sediment sources in agricultural and forestry watersheds with contrasting characteristics , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18835, https://doi.org/10.5194/egusphere-egu24-18835, 2024.

Soil loss due to crop harvesting (SLCH) is a globally occurring, but underestimated process that contributes to soil degradation, adversely affecting soil functionality and fertility. In northern Europe, sugar beets play a crucial role for SLCH due to their high production rates, yet there is a lack of research in commercial mechanized farming of sugar beets. The aim of this study is to measure SLCH for sugar beets using typical commercial harvesters and identify relationships to crop and soil variables. Therefore, sugar beets and soil samples were collected for 14 sampling sites between 2018 and 2020 in Northern Germany.

The results show that SLCH is in average 0.064 kg per kg sugar beet (SLCHspec), which corresponds to a loss of 5.7 Mg ha^-1 harvest^-1 (SLCHcrop). These numbers are higher than former comparable studies and 83.9 % higher than SLCH estimates by sugar beet factories. In addition, we found that i) SLCH considerably varies among years, fields, but also within fields, ii) the most influential drivers for SLCH are soil water content and clay content, iii) soil properties impact SLCH differently in dependence to soil water content, iv) SLCH of sugar beets can lead to significant nutrient and soil organic carbon losses. Thus, the results underline that SLCH is an important and underestimated determinant of soil erosion processes, which urgently needs to be considered in models and estimates additionally to concurrent processes like water, wind and tillage erosion. This is important for the adaptation of soil conservation measures in order to reduce ongoing soil degradation, especially in highly mechanized agriculture.

How to cite: Saggau, P., Busch, F., Brunotte, J., Duttmann, R., and Kuhwald, M.: Soil loss due to sugar beet harvesting is an underestimated but significant soil erosion process in mechanized agricultural systems., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19354, https://doi.org/10.5194/egusphere-egu24-19354, 2024.

Soil erosion is a natural geomorphological process, consisting of soil particle transport in the presence of water runoff. Despite its inherency, intensive human activity as well as acute climate change has led to an acceleration of soil erosion, and this becomes a major threat to environment and sustainability. In recent years, a rapid increase of rainfall frequency at the global scale enhances the production of surface runoff, thus yielding an active surface flow with higher velocity. Wetting-dry cycle induced by climate shifts also contributes to a vast distribution of fissure-containing surfaces, especially on soil-structure interfaces. Erosion triggered in this position can be detrimental, as the structure may lose its resilience against flood and earthquake, or even fails to maintain its gravitational stability. We herein introduce a novel laboratory-scale apparatus designed to investigate the surface erosion under high flow velocity, as well as the erosion of soil-structure interfaces featuring fissures. Our apparatus comprises three modules: a water circulation system, a testing chamber, and a set of data acquisition module. The testing chamber accommodates specimens measuring up to 24×80×80 mm with adjustable fissure widths. Monitoring module of particle removal and transport is emphasized in our study. With the reliable performance regarding repeatability tests using clayey soil, we found that the size of fissure significantly impacts the soil loss process, while its effect on the overall degree of erosion is minor. At different flow velocity intervals, similar successive steps, which involve alteration of single particle detachment and particle aggregate removal were witnessed at the soil surface. This was further validated by images captured by high speed camera and particle removal collection results. We believe that despite the simple framework of test apparatus, it is of great potential to further explore the surface erosion mechanism and the fissure development between soil-structure interfaces.

How to cite: Chen, C., Huang, W., and Chen, S.: A novel soil erosion apparatus for high-velocity surface erosion and fissure-containing soil-structure interfaces, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20092, https://doi.org/10.5194/egusphere-egu24-20092, 2024.

In natural environments, the occurrence of gravity erosion on slopes with vegetation is influenced by various external driving factors. Some are primarily controlled by the water field, such as rainfall infiltration, water level fluctuations, and freeze-thaw cycles, affecting the effective stress of the soil. Others are influenced by external loads transmitted to the soil through plants, affecting the original stress balance conditions, such as self-weight or wind force control. Additionally, extreme physical processes, such as wildfires and subsurface erosion, can degrade the soil strength and reduce the anti-sliding force. The investigations and experiments were conducted in the Chongqing section of the Three Gorges Reservoir Area in China. The triggering mechanisms and development patterns of gravity erosion on vegetated slopes under the influence of multiple factors were summarized from both field surveys and numerical models. Using remote sensing interpretation and numerical simulation, we estimated the potential volume of gravity erosion in the Chongqing section of the Three Gorges Reservoir Area in China. The research results indicate that the triggering factors for gravity erosion induced by rainfall and water level fluctuations are related to the soil entering the saturation process through the structural interface of the upper soil layer. This process leads to a reduction in matrix suction or the occurrence of positive pore water pressure. The essence of this phenomenon is the decrease in effective stress. The long-term instability of the surface soil layer in fire-affected areas is primarily due to the combined effects of root strength degradation and recovery, resulting in the deterioration of the overall shear strength of the soil. Wind disasters causing gravity erosion are attributed to local stress concentration and significant deformation induced by external loads, leading to traction and compression. Building upon the study of gravity erosion triggering mechanisms, the developmental process of gravity erosion was authentically reconstructed using aerial DEM and three-dimensional numerical models. The gravity erosion volume was estimated with a simulation accuracy of up to 92%. Additionally, the estimation of gravity erosion volume was extended to a regional scale, obtaining the potential gravity erosion volume in the Chongqing section of the Three Gorges Reservoir Area, with an estimated accuracy ranging from 35% to 60%. A protective solution utilizing vegetation measures is proposed to address gravity erosion induced by various external factors. For layered forested shallow slopes, consider permeable drainage through structural interfaces to address prolonged rainfall. For steep slopes with high wind exposure, consider the canopy-root plate type of afforestation species. In areas affected by fire disturbance, replanting and maintenance should be considered before the prone period of landslides. For riverbank slopes experiencing fluctuations in water levels, consider planting regenerative live stakes in the upper-middle part between the alert water level and the normal water level. Activate landslide disaster warnings when water levels drop rapidly.

How to cite: Wang, Y., Wang, B., and Wang, Y.: Study on the Regulatory Role of Vegetative Measures in the Development of Gravity Erosion, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20133, https://doi.org/10.5194/egusphere-egu24-20133, 2024.

Soil erosion by water and muddy flooding significantly threaten agricultural productivity and broader environmental health. This issue is widespread in the European Loess Belt, especially in Flanders, Belgium. The off-site impacts of muddy flooding – notably on water quality, ecosystems, and infrastructure – are catastrophic. Encouragingly, existing mitigation strategies that combine curative measures and farming practices have effectively managed soil loss and sediment transport. However, climate change is expected to greatly exacerbate these impacts, likely rendering existing mitigation measures insufficient. Despite a well-recognised need for adaptation, there is a continued lack of research dedicated to designing effective mitigation strategies for arable catchments facing an increased frequency and magnitude of muddy flood events in future. Our study explores adapting these measures for improved resilience to climate change, with a focus on a heavily impacted catchment in Limburg, Belgium. A modelling approach was used to predict future muddy flooding scenarios from 2021 to 2100, employing a novel methodology to select and downscale appropriate climate models for site-specific, daily resolution future climate scenarios. Soil erosion projections were generated using the WEPP model for four hillslopes under each climate scenario, while Erosion3D illustrated spatial erosion patterns across the catchment. Various likely land use choices and potential mitigation strategies under future climatic conditions were evaluated, with strategies shortlisted based on efficacy and farmer practicability. Our findings indicate a considerable increase in erosion magnitude and muddy flooding duration between 2041-2100 under current land management practices, with a marked increase in high-magnitude events. Conservation tillage emerged as the most effective strategy for 2021-2040, followed by no tillage for 2061-2080. Mixing summer crops with winter wheat is highly effective until 2080, but banning summer crops in vulnerable fields is necessary for 2081-2100. These findings underscore the need for better data – especially long-term muddy flood measurements – and enhanced public education on these issues, thereby offering insights applicable to other affected regions.

How to cite: Brannigan, N., Mullan, D., Vandaele, K., and Graham, C.: Mitigating muddy flooding in a changing climate., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21528, https://doi.org/10.5194/egusphere-egu24-21528, 2024.

Soil erosion, a global challenge with profound consequences, impacts soil nutrient depletion, land degradation, agricultural productivity, runoff, and geological hazards. Our study assesses soil erosion and land use changes in the Beas Valley, Kullu, Himachal Pradesh, situated in the Western Himalayas. Employing diverse datasets and a comprehensive methodology, we scrutinize the intricate interactions of climate, soil, topography, and land use to comprehend and mitigate soil erosion risks. Data sources include rainfall data from the Climate Research Unit at the University of East Anglia, soil data from the Food and Agriculture Organization, Digital Elevation Model (DEM) data from the Shuttle Radar Topography Mission, and Landsat satellite imagery. We utilize the Revised Universal Soil Loss Equation (RUSLE) for soil erosion assessment, which includes factors like erosivity (R-factor), erodibility (K-factor), slope and flow accumulation (LS-factor), vegetation cover (C-factor), and conservation practices (P-factor).To bolster the credibility of our findings, we complement our methodology with field observations and interviews. These on-ground assessments and stakeholder insights provide practical context and verification for our research. This interdisciplinary approach yields crucial insights into soil erosion and land use changes in the Beas Valley, enriching our understanding of soil erosion in this fragile Himalayan ecosystem. Our findings offer vital support for informed land management decisions and conservation efforts.

Keywords: Soil erosion assessment, Himalayan, RUSLE, GIS and Remote Sensing

How to cite: Maurya, S., Singh, V., Chand, K., and Mishra, P.: Assessment of the spatial distribution of soil erosion using the RUSLE model and field survey study - A case study of Beas Valley, Kullu, India, Western Himalaya , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-135, https://doi.org/10.5194/egusphere-egu24-135, 2024.

Soil erosion causes worldwide land degradation. Long term monitoring of soil erosion is costly and labor intensive. Multiple models using Cs-137 fallout from atomic bomb tests are developed to retrospectively estimate average soil erosion since 1954. However, those models have not been rigorously validated due to the lack of compatible long-term measured soil loss data and thus their usefulness has been seriously challenged. Using 70 years of rare soil loss data measured in two small watersheds of <0.78 ha during 1954 and 2015, the author found that all theoretical models overestimate mean net soil erosion rates by at least 400%, and further confirmed that a key assumption of the homogeneous Cs-137 transfer from rainwater to soil during fallout is invalid and a critical process of the enhanced Cs-137 loss and redistribution during transfer is overlooked. The enhanced Cs-137 uptake by suspended sediment during transfer was responsible for about 8 times more enriched Cs-137 loss in sediment, to which Cs-137 inventory and erosion estimation are extremely sensitive. A new mass balance model is developed to include the dynamic uptake of Cs-137 by suspended sediment in surface runoff and losses of Cs-137 in both runoff solution and uptake by plants. The new model reduced overestimation of soil erosion to about 30%.  The finding of the enhanced radionuclide loss with suspended sediment during transfer is also valid to other fallout radionuclides such as Pb-210 and Be-7, which have been widely used in soil erosion estimation. Taking into account the enhanced radionuclides loss by suspended sediment during fallout will substantially lower soil loss estimation by all fallout radionuclides. 

How to cite: Zhang, X. C. J.: Evaluating and improving cesium-137 technology for estimating soil redistribution using soil loss data measured during 1954-2015, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4180, https://doi.org/10.5194/egusphere-egu24-4180, 2024.

Soil erosion modelling has a large sensitivity to soil water content as it greatly affects soil erodibility. Knowing soil moisture and water content along a soil profile can help to understand the soil ability to absorb water before runoff occurs, then, to predict runoff and potential erosion.

This study presents a combined approach of direct and indirect methods to monitor soil moisture content on a slope, with the goal of using this data in the future for modelling water erosion processes in soils.

Generally, soil moisture data used for erosion models can be acquired through direct methods (e.g., gravimetric method, time or frequency domain reflectometry, moisture sensors) and/or indirect methods (meteorological data, remote sensing, electrical conductivity).

In this research project, an experiment was carried out with the aim of combining direct and indirect methods to maximize the information on the rate of change of soil moisture in a 9*9 m plot by exploring depths from 0 to 50 cm. We used the water content sensor, SoilVUE10 by Campbell, recently released on the market, and based on Time Domain Reflectometry (TDR) technology conjointly with the Electrical Resistivity Tomography (ERT). Moisture sensors are known to create a disturbance in the ground, while geophysical techniques such as ERT are indirect, non-destructive measurements. Furthermore, they have the great advantage of being able to investigate a significantly larger area than classic humidity sensors.

The conductivity varied in average between 0.02 and 0.08 S/m with a little more evident relationship between the values measured with the two methods in deeper layers than at soil surface (i.e., r=0.31 at -30cm).

Overall, further investigations will be conducted, the ERT system needs data acquisition integration, i.e., remote data acquisition so that much more data can be acquired (at least one data set per day). The moisture values acquired by the SoilVUE10 probe require further analysis and comparison, possibly with other TDR probes. Furthermore, it may be necessary to install a surface moisture sensor capable to improve data acquisition even for the first 10cm soil layer.

How to cite: Innocenti, A., Pazzi, V., and Fanti, R.: Correlating different evaluation methods for SWC as support for soil processes modelling , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10794, https://doi.org/10.5194/egusphere-egu24-10794, 2024.

This study focuses on the evolution of soil erosion rates on artificial covers for low level radioactive waste in the context of climate change. The objective is to test the impacts on erosion of (i) increasing rainfall intensities during storms and (ii) decreasing soil moisture content before storms. The “Centre de stockage de la Manche” (CSM) in Normandy, France, where Low-Level Nuclear waste are stored and monitored for the next centuries, is used as a reference case. There, climatic models anticipate an increase of temperature and seasonality (i.e., dryer Summers and wetter conditions from Fall to Spring) in the next centuries.

First, the soils of the CSM are sampled to be characterized. The densities, moisture, grainsize distribution and organic content of the soil are measured. We find that these values are rather homogeneous at the scale of the CSM. Second, a series of experimental rainfall simulations is performed on the CSM soils, focusing of rates and distribution of erosion processes. We simulate rainfall events of decennial, centennial, millennial and decamillennial intensities on 18° slopes, corresponding to the steeper banks of the CSM. Using the capacities of the climatic chambers at the Ecotron Lab in Nemours, France, we further test several soil moistures, i.e., very wet, moderately wet and dry, before simulating rainfall events. Finally, each experiment is repeated several times to assess the “memory” effect of topography on erosion. We quantify erosion by measuring sediment concentrations in run-off water collected at the outlet of the model and using topographic acquisitions performed using photogrammetry.

The experimental results are compared with estimations based on the Revised Universal Soil Loss Equation. Some propositions for upscaling, which could be used for assessing hypothetical future increase in soil loss in the CSM, are discussed.

How to cite: Portzer, G., Grimaud, J.-L., Marchiol, A., Stab, O., Fleurisson, J.-A., Abiven, S., Chollet, S., Maalouf, Y., Khoueiry, N., and Yadari, N.: Experimental simulation of soil erosion in the context of climate change in NW France., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11138, https://doi.org/10.5194/egusphere-egu24-11138, 2024.

Research and action agencies in the US work collaboratively to develop and use soil erosion technology to support the development of field-specific conservation plans. These tools and accompanying databases are applied in all counties throughout the country covering a wide range of natural and anthropogenic physical conditions. Climate, particularly precipitation, constitutes one of the key drivers directly related to soil detachment and transport. Observations spanning over 30 years have demonstrated that estimated long-term average annual soil loss in agricultural fields is the result of the cumulative effect of many small and moderate-sized storms along with the impact of occasional severe ones. In the Revised Universal Soil Loss Equation version 2 (RUSLE2) technology, the effect of rainfall is represented by the rainfall runoff erosivity index R. This index is designed to serve as an estimation of the potential storm energy specific to each location. In this study, we propose and evaluate a methodology to generate continuous surfaces of monthly R for the continental US from discrete 15-min precipitation data. Over 2000 stations covering more than 50 years of 15-min precipitation data were used. Storm identification algorithms were implemented and evaluated through comparison with existing tools. Outlier events were identified and removed using a 50-year recurrent interval calculated for each station. Using 30-years of recorded data, a custom universal kriging algorithm was employed to generate a smooth continuous surface as a raster grid. This step included a boxcox transformation of the station data, directional variogram fitting, and the removing of external trends using elevation, long-term annual precipitation totals, and distance to the coast. Predicted surfaces were compared with existing RUSLE2 surfaces for the same time period with great level of agreement. The proposed methodology is intended to be comprehensive and reproductible such that it can serve as a template for future updates of erosivity maps for the entire continent at a county-scale. This methodology provides the means for future systematic updates to the RUSLE2 climate database to account for climatic changes and to support continued national efforts in reducing soil erosion and conserving natural resources. 

How to cite: Momm, H., Wells, R., Seever, T., ElKadiri, R., and Bingner, R.: Methodology for Spatially Distributed Rainfall Erosivity Calculations at the Conterminous United States to Support Soil Erosion Studies, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11387, https://doi.org/10.5194/egusphere-egu24-11387, 2024.

AnnAGNPS (ANNualized AGricultural NonPoint Source model) is a watershed-scale hydrologic model designed to analyze the impact of non-point pollutants in predominantly agricultural watersheds. It has capabilities that make it unique and indispensable on the world scene, such as an integrated simulation of all types of erosion and all major sources of non-point agricultural pollution. However, AnnAGNPS does not currently have a graphical user interface that allows the user to perform the simulation in a simple way. It is in this context that QAnnAGNPS has been created. QAnnAGNPS is a model developed in QGIS and written in Python 3 that fulfills two general functions. The first is to provide a simple to use graphical user interface to run AnnAGNPS. The second is to incorporate extra functionalities to the model, which are already included in similar hydrological models. The plugin has been used in the simulation of the Latxaga basin, a 207-hectare cereal basin located in Navarra (northern Spain). Its use has allowed to verify that QAnnAGNPS is able to perform the AnnAGNPS simulation and to visualize the results in a simpler way than the original one.

How to cite: Barberena, I., Campo-Bescós, M. A., and Casalí, J.: QAnnAGNPS: a new plugin in QGIS to facilitate the use of AnnAGNPS, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17727, https://doi.org/10.5194/egusphere-egu24-17727, 2024.

Water erosion is a current issue, especially in hilly and areas, where driving force such as surface runoff and subsurface flow can mobilize large amounts of sediment to rivers. In fact, how and at which timescale, seasonality precipitation is turned into runoff or streamflow (Q) it is difficult to be predicted without calibrating site-specific models. The potential soil erosion can be assessed through the study of the relationships between sediment sources and sinks in a watershed (i.e., sediment connectivity assessment) and associated suspended sediment (SS) transport in rivers. On the other hand, sediment connectivity, defined as structural (from a geomorphological point of view) and functional connectivity (considering forcing processes), can be evaluated by the using of specific indexes (e.g., Index of connectivity – IC).  SS transport processes are intermittent processes fluctuating over a large range of temporal and spatial scales, making it challenging to develop predictive models applicable across timescales and rivers. While temporal variability in sediment transport is explained by the concept of “effective timescale of connectivity”; the mechanism behind this variability remains unknown. Here we used a data-driven approach considering two years of monitoring Q and SS to develop and demonstrate a proof of concept for automating the classification of event-based sediment dynamics by using a machine learning approach.  For each storm event we i) calculate the sediment connectivity (extreme rainfall events also are considered) and ii) define the link between sediment transport and deposition by considering SS transport as a fractal system (i.e. fractal storage time distributions in streams). Fractals are here used to describe and predict patterns over different temporal scales of dynamics in SS   The statistic and dynamics of Q, SSCs and associated grain size distribution, at event based, were considered by assessing their probability distribution function, Fourier power spectra, and the machine-learning classification of hysteresis index. Indeed, by approaching SS transport dynamics as a fractal system, it is assumed that patterns of variation in SS transport exist over different timescales, while linkages across those temporal scales are expressed as fractal power-laws. The study site, located near Florence in the Chianti area, is a 1 Km² agricultural watershed with different types of land cover and characterize by a first-order mixed bedrock and alluvial stream channels. The area was mapped at high resolution with a Drone LIDAR scanner and equipped with a submersible laser diffraction particle size analyser (LISST) for long-term measuring suspended particle size and its volume concentration. Preliminary results showed a robust correlation between sediment connectivity, land cover, and sediment connectivity. Q-SS information flows exhibit seasonally varying behaviour consistent with dominant runoff generation mechanisms (catchment connectivity in wet to dry season). However, the timing and the magnitude of runoff also reflect considerable catchment heterogeneity, likely attributable to differences in baseflow contributions from different lithologies, and variation in of preferential flow paths (land use/land cover).  In conclusion, this study allowed to analyse a small catchment area in term of sediment connectivity and related sediment transport to identify potential areas of (dis)connectivity in the basin.

How to cite: Barbadori, F., Pelacani, S., and Raspini, F.: Investigating water erosion dynamics through connectivity based on fractal approaches: A case study in the Chianti area (Florence, Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18276, https://doi.org/10.5194/egusphere-egu24-18276, 2024.

Soil processes are known to stretch over many scales – some processes, like erosion, are of particular interest due to their quick and complex characteristics with high impact. The analysis of soil erosion processes is challenging through heterogeneous field situations, involved spatio-temporal scales and by a reconfiguration of the system itself. Various experimental procedures and analytical methods were developed, which can analyze erosion processes. But because the procedures are driven by specific model assumptions which in effect also relate to a plethora of central state variables and parameters, the data of different groups are rarely compatible. Interoperability is hindered further through inhomogeneous data structures and a lack of metadata.

Within the NFDI4Earth pilot SoilPulse (soilpulse.github.io) we are developing an interactive metadata generator which shall assist researchers to make their soil process related data sets reusable by humans and machines. Instead of forcing the user to adhere to a defined metadata standard, the tool semi-automatically and interactively builds a translation procedure i) to map various existing data structures to a common scheme and ii) to feedback valuable but missing information to be provided by the researcher. While treating a dataset the researcher is aided by visualizations of the data in relation to other datasets which are already made machine readable through SoilPulse, allowing to easily discover non-plausible data and errors within the dataset. Once treated the dataset can be queried along with other datasets through a common interface and can be linked to erosion models through an API.

The PICO presentation demonstrates the functionality of the SoilPulse metadata generator prototype and invites attendees to apply it themselves on their data sets. As SoilPulse is in active development we highly appreciate comments, hints and impulses to further improve the tool!

How to cite: Lenz, J., Devátý, J., and Jackisch, C.: SoilPulse – Towards FAIR soil process data!, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19497, https://doi.org/10.5194/egusphere-egu24-19497, 2024.

Gully erosion seriously affects the landscape and human life in different ways by destroying agricultural land and infrastructures, altering the hydraulic potential of soils, or affecting the water quality and quantity. Due to climate change, the negative effects of gully erosion are likely to increase in future, threatening especially low-income agricultural regions. In the past decades, quantitative methods have been proposed to simulate and predict gully erosion at different scales. However, gully erosion is still underrepresented in modern GIS-based modelling and simulation approaches. Therefore, we developed a tool to assess gully erosion dynamics. This tool comprises the data preparation, modelling and output analysis of the modelling phase as well as the visualization of the results. The modelling procedure is based on Sidorchuk’s gully simulation model. The tool was developed using phyton and the QGIS environment.

How to cite: Maerker, M., Pelacani, S., Omran, A., and Sidorchuk, A.: An integrated GIS tool for gully erosion modelling , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20845, https://doi.org/10.5194/egusphere-egu24-20845, 2024.

Radar-based rainfalls are currently used for process monitoring from remote in a large panel of domaines including hydrology and soil erosion modelling. Nevertheless, such data may include systemic and natural perturbations that need to be corrected before using these data. To encompass this problem, adjustments based on raingauge observations are frequently adopted. Here, we analysed the performance of different radar-raingauge merging procedures using a regional raingauge-radar network (Tuscany, Italy) focusing on a selected number of rainfalls events.

The computational methods adopted were: 1) Kriging with External Drift (KED) interpolation (Wackernagel 1998), 2) Probability-Matching-Method (PMM, Rosenfeld et al., 1994), and 3) an Adjusted kriging mixed method exploiting the conditional merging (ADj) process (Sinclair-Pegram, 2005). The latter made available by DPCN (Italian National Civil Protection Department), while methods 1) and 2) were applied on recorded raingauge rainfalls over the regional territory at 15’ time-step, and CAPPI (Constant Altitude Plan Position Indicator) reflectivity data from the Italian radar network at 2000/3000/5000 m at 5’ and 10’.

The comparisons between the three rainfall fields were based on the analyses of variance, Cumulative Distribution Function (CDF), and explicative coefficients such as BIAS, RMSE (Root Mean Square Error), MAD (Median Absolute Deviation). In average, rainfalls showed a moderate variability between the methods. Comparing CDFs, slight differences were detected between KED and ADj with bias mostly pronounced in lower quantiles, while more marked differences are observed in higher quantiles for the ADj-PMM methods. The analyses presented different spatial patterns depending on the applied procedure, closer to the radar data when using ADj, and more reflecting the gauge’s data structure when adopting KED. The probabilistic method (PMM) had the advantage to account for gauge data while preserving the spatial radar patterns, thus confirming interesting perspectives. Globally, the KED method provided more accurate coverage in the calculation by better compensating for local topographical shadows in the data, while ADJ confirmed the more detailed product in terms of time resolution (e.g. 5minute res.).

How to cite: Moretti, S., Ciampalini, R., Antonini, A., Mazza, A., Melani, S., Ortolani, A., Rosi, A., and Segoni, S.: Comparing radar-raingauge precipitation-merging-methods for soil erosion modelling support, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21549, https://doi.org/10.5194/egusphere-egu24-21549, 2024.

Accurate estimation of infiltration rates is crucial for hydrological modeling, impacting predictions of runoff, sediment transport, and related phenomena. Various infiltration models, categorized as empirical, semi-empirical, and physically based, have been developed to compute cumulative infiltration and infiltration rates for these purposes. Because of its simplicity and accuracy, the Green–Ampt (GA) infiltration equation has been widely used for simulating 1-D (vertical) infiltration into the soil. The modification of GA equation by Mein and Larson for steady rainfall conditions (GAML,1973., etc.,) is widely employed in different hydrological modeling software such as ANSWERS (Areal Nonpoint Source Watershed Environment Response Simulation), CREAMS (Chemicals, Runoff, and Erosion from Agricultural Management Systems), and WEPP (Water Erosion Prediction Project), suggests the versatility of the model approach. However, its assumption of a sharp wetting front and uniform soil moisture content tends to overestimate low-flow runoff events. The present study proposes a simple, standalone methodology to refine the GAML equation employed for infiltration calculations in the WEPP model. The advantage of the WEPP model is that it can simulate runoff and soil loss events on an hourly, daily, monthly, annual, and event scale; Spatial and temporal distribution of soil loss and deposition can be estimated, and hillslope to watershed scale studies can be performed. Refinement entails estimating hydraulic conductivity (K) and soil moisture (ϴ) distribution in vertical and horizontal (2D) soil matrices before and after ponding scenarios as a linear equation of infiltration. A new algorithm was developed based on the refined GAML (R-GAML) parameters to estimate revised ponding time and infiltration rates based on experimental results, enhancing the accuracy of runoff predictions. Laboratory experiments on sand, clay, and sandy clay soils are utilized to estimate the soil infiltration parameters. The WEPP model was then employed to simulate runoff for a small agricultural watershed with the outlet at T. Narasipura station (of Cauvery River, India). The R-GAML and conventional GAML equations were used for runoff simulation and validated with the observed runoff data. The overestimation of low-flow runoff events using the conventional GAML was substantially reduced by the newly developed method, and the performance of R-GAML versus GAML was evaluated using correlation coefficient (0.937, 0.905), RMSE (16.471, 35.905), and NSE (0.968, 0.915) performance matrices for the Indian context.  Furthermore, this research aims to extend i) runoff and sediment yield (SY) simulation using the R-GAML equation from the field scale to the river basin scale (upscaling), ii) study the impact of Land Use and Land Cover (LULC) change on runoff and SY production by multi-site and multi-temporal calibration approach using the WEPP model. The findings offer valuable insights for urban planners in designing drainage networks, for agricultural water management in scheduling reservoir water release, and for deriving Best Management Practices (BMPs) in the Cauvery basin, which faces transboundary challenges due to rising water demand.

How to cite: Suliammal Ponnambalam, V. and Dasika, N. K.: Innovations in Hydrological Modeling: A Standalone Approach to GAML Equation Enhancement for Runoff and Sediment Yield Estimation Using WEPP model, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3323, https://doi.org/10.5194/egusphere-egu24-3323, 2024.

I am a doctoral candidate in University of Trento (first year) in Earth Observation at the Department of Civil, Environmental and Mechanical Engineering. My administrative University is Sapienza University of Rome and I am writing to express my interest in presenting my research in developing the strategies to predict Rill and Gully erosion in EGU general assembly 2024.

Soil moisture plays a major role in assisting crop productivity and weather forecasting to satisfy the ever-growing demands for land resources.

Soil erosion mechanics involve fluid (water/wind) detachment or entrainment followed by transport of soil particles and subsequent deposition as soil sediment. Soil movement by water often starts when a raindrop impacts the soil surface and initiates splash erosion, i.e., raindrops break aggregates into finer soil particles, displacing those particles and aggregates to create depressions in the soil surface. It depends on rainfall intensity, soil erodibility, and field slope among other factors. 

Various factors affecting soil erosion, including soil slope and length or supporting control practices like contour rows, strip cropping, and terrace systems, were recognized as independent factors influencing soil erosion by their inclusion in regional soil-loss equations. Water Erosion Prediction Project has been used to predict soil loss in a range of environments such as rangeland and forest for simulating runoff and sediment yield from the untreated watershed with good accuracy using continuity equation :

(dG/dx)  =  D_r + D_i 

G = sediment load (kg·s^-1· m^-1)

x = distance down slope (m)

D_r = rill erosion rate (+for detachment, - for deposition)

D_i = interrill sediment delivery (kg·s⁻¹·m⁻²).

Water Erosion Prediction Project relates sediment load in the runoff to the distance downslope as a function of the interrill and rill erosion rates calculated on a daily time step. Interrill erosion is the process of sediment delivery to more concentrated flow in rills, but rill erosion depends on the potential detachment capacity as limited by the sediment transport capacity of runoff in the rill. Soil loss through interrill and rill erosion is associated with the factor known as Revised Universal Soil Loss Equation (RUSLE), formulated as :

A  = R∗K∗L_s∗C∗P

A is the annual soil loss due to erosion [t/ha year];

R the rainfall erosivity factor;

K the soil erodibility factor;

L_S the topographic factor derived from slope length and slope gradient;

C the cover and management factor; and

P the erosion control practice factor.

The limitations of RUSLE are that it only accounts for soil loss through sheet and rill erosion and ignores the effects of gully erosion. 

The objective is to generate gully erosion susceptibility maps (GESMs) by applying three machine learning algorithms to identify the area of the basin with respect to total area, which prones to have higher or lower susceptiblity to gully erosion.

These erosions require Persistent Monitoring with the combination of three main elements. High resolution, Revisit rate and global coverage. The models can be developed using GIS or R software and from SAR technologies.

Considering my academic performance so far, I hope to have this opportunity to present in EGU assembly, as I am confident that I will be able to meet your expectations.

Thanking you.

How to cite: Kaparthi, H. V. and Vitti, A.: Development of observation model for predicting the phenomena of Rill and Gully erosion using Machine learning, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6562, https://doi.org/10.5194/egusphere-egu24-6562, 2024.

Concentrated runoff increases erosion and moves fine sediment and associated agrichemicals from upland areas to stream channels. Ephemeral gully erosion on croplands in the U.S. may contribute more of the sediment delivered to the edge of the field then from sheet and rill erosion. Typically, conservation practices developed for sheet and rill erosion are also expected to treat ephemeral gully erosion, but science and technology are needed to account for the separate benefits and effects of practices on each of the various sediment sources.

Watershed modeling technology has been widely developed to aid in evaluating conservation practices implemented as part of a management plan, but typically lacks the capability to identify how a source, such as sheet and rill erosion, ephemeral gully erosion, or channel erosion, is specifically controlled by a practice or integrated practices. The U.S. Department of Agriculture’s Annualized Agricultural Non-Point Source pollutant loading model, AnnAGNPS, has been developed to determine the effects of conservation management plans on erosion and provide sediment tracking from all sources within the watershed, including sheet and rill, ephemeral gully, and channel erosion. 

This study describes the ephemeral gully erosion capabilities within the AnnAGNPS model and discusses research needs to further improve these components for integrated conservation management planning.  Conservation management planning by agencies within the U.S. and by international organizations requires a systematic approach when determining the extent of ephemeral gully erosion impacts on a field, watershed, or national basis, and/or to predict recurring or new locations of ephemeral gullies prior to their development.  This technology provides the capability to separate the impact of ephemeral gullies on erosion from other sources and then evaluate the impact of targeted practices to control erosion at the source and subsequent downstream resources.

How to cite: Bingner, R., Wells, R., Momm, H., and Locke, M.: Enhanced Ephemeral Gully Erosion Science within AnnAGNPS , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6677, https://doi.org/10.5194/egusphere-egu24-6677, 2024.

Concentrated-flow erosion and sheet erosion are main drivers of soil loss in Mediterranean agroecosystems with soft lithologies. Morphologies of concentrated-flow erosion were assessed in a terraced rainfed almond crop (Prunus dulcis Mill.) located on Tertiary marls in SE Spain, using two methodologies: i) field inventory and ii) photogrammetry through images taken with RPAS (Remotely Piloted Aircraft System). Both methods were applied to compare their results within one year after three major rainfall events. For the application of the field inventory, each morphology was divided longitudinally, measuring their dimensions (width, length and depth) to estimate the volume of mobilized material following the shape of each division. RPAS images were processed to obtain digital elevation models (DEMs) and orthophotos, which were subsequently used to identify erosional morphologies and calculate the volume of mobilized material through variation in height and resolution of the DEMs. Sampling for soil’s bulk density was carried out to convert volume into mass. Differences between second and first inventory or flight (period 1), and between third and second ones (period 2) were calculated to estimate sediment yield rates.

Erosional morphologies, identified with both methodologies, were: i) rills, mainly along terraces; ii) gullies, mainly on the edges of terraces; and iii) mass movements, only on the edges of the terraces. Moreover, a fourth form not described in previous studies was identified, called mixed erosion: a joint action of laminar and concentrated flow under extreme rainfall conditions. This form appeared at the base of gullies and, occasionally, connecting gullies.

In period 1, gullies showed higher median sediment yield than rills, both with field inventory (1,3 ± 1,7 y 0,22 ± 0,11 t ha^-1 y^-1, respectively), and photogrammetry (1,37 ± 1,01 y 0,24 ± 0,2 t ha^-1 y^-1, respectively). While, in period 2, mixed forms and gullies were more erosive than rills and mass movements, both with field inventory (8,8 ± 0,9, 2,4 ± 1,9, 0,54 ± 0,48 and 1,1 ± 0,8 t ha^-1 y^-1, respectively), and photogrammetry (1,7 ± 1,1, 1,2 ± 0,9, 0,23 ± 0,18 and 0,15 ± 0,11 t ha^-1 y^-1, respectively).

69, 16 and 50 % of the rills, gullies and mass movements, respectively, identified through inventory method were also identified with RPAS images. In contrast, all of the mixed erosional morphologies identified in the field survey were vissible in the RPAS images. The proportion of rills and gullies identified simultaneously with both methods increased in successive samplings, likely due to the increased intensity of the successive rainfall events, resulting in more easily identifiable features. Finally, for those morphologies identified with both methods, the RPAS sediment yield estimations were 40 – 50 % higher than those made by inventory method, probably due to the difference in resolution between methods.

The mixed form of erosion and the gullies showed a high erosive potential, involving a great environmental threat on this kind of agroecosystems. At a relatively low cost, RPAS, through its greater resolution, can help to get more reliable values of concentrated erosion rates in rainfed agroecosystems than field inventories.

How to cite: Carrillo-López, E., Calvo Cases, A., Pérez Cutillas, P., and Boix-Fayos, C.: Comparing different approaches to measure erosion by concentrated flow in a rainfed agroecosystem in SE Spain: Field inventory vs RPAS, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7471, https://doi.org/10.5194/egusphere-egu24-7471, 2024.

The current evolution of climate in Southern Europe, apparently enhances the frequency and persistence of rainless spells, with interspersed short and intense rainfall events. Both circumstances exacerbate the soil erosion episodes, particularly in the olive cropped landscapes, with the consequent risk of soil productivity loss and the dispersion of pollutants. The most common erosion form, gully erosion, act as preferential ways for the removal and dispersal of runoff and sediments.

Although the near-future climate scenarios are uncertain, new and more effective integrated management systems need to adopted to preserve both the food generation potential, and the environment.

The purpose of this work is to analyze some techniques for the assessment of the gully erosion, from the photo-interpretation of the sequence of historical photograms, including Machine Learning methods to avoid the subjectivity of the observer, to the acquisition of new multi-spectral images with UAV. The nest step is the selection of the optimal location of the prevention, such as cover crops and vegetative barriers, and control, like check-dams for the interception of runoff and sediments.

The final outcome of the proposed techniques is the use of the fill-and spill concept to enhance an intermittent connectivity in the gully networks with the additional advantage of the increased biodiversity in the landscapes.

How to cite: González Garrido, P., Peña, A., Vanwalleghem, T., and Giráldez, J. V.: Analysis of some gully control techniques for the conservation of olive cropped landscapes in Southern Spain, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7648, https://doi.org/10.5194/egusphere-egu24-7648, 2024.

Ephemeral gullies (EGs) are channels that form in low parts of the field where runoff concentrates, and are often responsible for considerable soil loss from agriculture fields. Unfortunately, predicting the gradual development of gullies in response to storm events remains challenging. The United States Department of Agriculture has developed several modeling tools to predict the location and dimensions of ephemeral gullies and the resulting soil loss. The tool described herein combines precise geospatial determination of EG pathways with soil erosion and delivery calculations for both those pathways and the contributing hillslopes.

Considering the vital importance of determining runoff concentration for EG development, high-resolution (0.5 ~ 3 m) terrain elevation data are processed with specialized geospatial tools to determine topography-driven surface runoff patterns and define swales where concentrated flows occur.  This creates integrated surface drainage descriptions defining hillslope areas where sheet-and-rill erosion predominates, and swales where EG gullies may develop. This results in detailed flow maps covering entire fields, optionally considering oriented roughness created by crop rows on flow distribution.  These data, along with topography-derived parameters and spatial distributions of soil types and vegetation cover, form the digital landscape description for erosion modeling.

The magnitude, frequency, and seasonal distribution of storms are represented by a synthetic series of events derived from long-term climate databases created for the RUSLE2 (Revised Universal Soil Loss Equation, version 2) model.  Runoff for each storm event is estimated with RUSLER (RUSLE2-Raster), a two-dimensional (2D) raster implementation of RUSLE2 technology that calculates runoff and sheet-and-rill soil loss for all flow paths covering a field.  The RUSLER calculation provides the spatial and temporal distribution of incoming runoff and sediment loads necessary for the calculation of erosion and deposition in the EG channels.

The channel flow and sediment transport model EphGEE (Ephemeral Gully Erosion Estimator) employs an excess shear stress approach to determine where flow erosive forces cause soil detachment and transport, and where deposition occurs.  EphGEE also calculates the rates at which channels locally deepen and widen, thus predicting how channel geometry evolves during each storm, which depends strongly on knowledge of soil erodibility parameters. EphGEE attempts to estimate how erodibility parameters vary in time and with depth using management operations data available from RUSLE2 databases. In most cases, however, field data and parameter calibration are still necessary.

This modeling approach has been applied to monitored fields in the United States.  It was successful in determining runoff and concentrated flow paths, resulting in good predictions of locations where gullies form and how they connect to runoff-generating areas.  For tilled fields where a less erodible soil layer exists, the model provides good approximations of gully depths and widths. For no-till and pasture-to-crop transitions, where EG cross-sectional shapes may be dependent on how erodibility varies with soil depth, better data or prediction methods are needed to improve model performance.

How to cite: Vieira, D., Wells, R., Yoder, D., and Bingner, R.: Event Based Modeling of Ephemeral Gully Development in Agricultural Fields, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12354, https://doi.org/10.5194/egusphere-egu24-12354, 2024.

The severe erosion problems affecting large areas of olive groves on slopes in Andalusia (Spain), whose soil losses exceed 40 kg m-2an  in extreme rainfall events, require an integrated watershed management run by landowners and state or regional agencies.

The most common, and most severe erosion form is gully erosion. Gullies act as preferential ways through which soli particles with adsorbed nutrients and agrochemical substances spread downslope moved by surface runoff, what implies a great water loss.

During the last four years a cooperative innovation project between the University of Cordoba and two joint venture groups to (i) evaluate the extent of the soil loss in selected slopes, (ii) estimate the density and location of check-dams to intercept the water and sediment flows; (iii) design a novel type of modular dams; and (iv) complement th conservation works with new cover crops mixtures.

A by-product of this project is the development of an automatic model for the spatiotemporal evolution of gully networks based on the D8 flow direction algorithm, and a network branches detection scheme to accumulate flow identifying the final outlet.

This model has been successfully applied to two olive cropped slopes of Southern Spain.

The innovative proposal has allowed for: (a) Generation of the DEM (Digital Elevation Model) for hydrological modeling of watersheds and determination of gullies and areas vulnerable to erosion; (b) Development of algorithms for a topologically connected network of gullies to establish the areas of origin of soil loss and sediment deposition (c) Protection and correction of ephemeral and deep gullies in pilot plots by means of dikes of modular pieces, vegetation covers in crop roads, protection of roads and vulnerable areas through native plantations, and burying of pruning remains; (d) Monitoring and follow-up of measures from LiDAR sensors on board UAVs and soil analysis before and after extreme events.

These initiatives have already been successfully tested in several projects in which the University of Cordoba participates, such as the CPI INNOLIVAR project and the HIDROLIVAR Operational Group and will be implemented in new study basins where excellent results are expected due to the fragility of steep slope olive groves in very degraded soils.

How to cite: Peña, A., González-Garrido, P., Laguna, A. M., and Gámiz, A. M.: Automatic generation of topologically connected gully networks for integrated erosion control in sloping olive orchards, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12394, https://doi.org/10.5194/egusphere-egu24-12394, 2024.

Ephemeral gullies (EGs) are major contributors to sediment loss and land degradation on cultivated lands. EG is an important linear erosion feature, often occurring at mid-slope position, that can be greatly influenced by upslope and lateral inflow. This study quantified the ephemeral gully erosion influenced by the upslope and lateral inflow, and the results showed that upslope and lateral inflow both contributed to the runoff connectivity of the EG channel and lateral rills in the EG system. For these simulated conditions, upslope inflow contributions to total runoff and soil loss were 62–78% and 65–81%, respectively, while lateral inflow only contributed around 10%. The contribution differences could be attributed to flow hydrodynamic characteristics in that shear stress and stream power in the EG channel were 4.9–8.6 times greater than those on the lateral slopes. From sheet flow to rill flow and EG channel flow, the flow regime gradually shifted from laminar and subcritical flow to turbulent and supercritical flow. The flow force, power, and energy correspondingly increased as the flow regime changed toward turbulent and supercritical. Both field monitoring and indoor simulation displayed the additional sediment delivery caused by upslope sediment-laden flow, verifying the transport-dominated sediment regime in EG systems. In field observations, the sediment increment coefficient (SIC, ratio of net sediment delivery caused by upslope sediment-laden flow to the total sediment delivery) on an event scale varied from 4.6% to 88.6%. In indoor simulations, the SIC changed from 24.9% to 87.5%. The SIC linearly decreased as the sediment concentration of upslope inflow increased. Field monitoring showed complicated phenomena because of natural random variations. SIC also generally decreased as the sediment concentration of upslope inflow increased. Laboratory simulations verified the field monitoring results of extreme rainfall events with large rainfall amounts and intensities. In future studies, multiple morphological criteria defining EG under various environments are urgently needed. Similar to the continuous sediment transport equations for rill erosion, continuous sediment transport equations for EG erosion need to be developed.

How to cite: Xu, X.: Quantification Studies on Ephemeral Gully Erosion, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14301, https://doi.org/10.5194/egusphere-egu24-14301, 2024.

Purpose: The characterization of soil properties is an important part of many different types of agri-environmental research including inventory, comparison, and manipulation studies. Sediment source fingerprinting (i.e., tracing) is a method that is increasingly being used to link sediment sources to downstream sediment. There is currently not a standard approach to characterizing sources and the different approaches to sampling have not been well assessed.

Methods: Grid, transect, and likely to erode sampling designs were used to characterize the geochemical, colour, grain size distribution, and soil organic matter content at two sites under contrasting land uses (agricultural and forested). The impact of the three sampling designs on fingerprint selection, source discrimination, and mixing apportionment results was evaluated using a virtual mixture.

Results: The sampling design had a significant impact on the characterization of the two sites investigated. While the number and composition of the fingerprints selected varied between sampling designs there was strong discrimination between sources regardless of the sampling approach. There were deviations in the expected apportionment results, but the overall patterns were similar across the three sampling designs.

Conclusions: Despite having an impact on the characterization of sources, the sampling design used ultimately had little impact on the conclusions drawn from the final apportionment results. Continued work at the watershed scale is needed to fully evaluate the importance of source sampling on the sediment source fingerprinting approach.

How to cite: Luna, M., Koiter, A., and Lobb, D.: Effect of Sampling Design on Characterizing Surface Soil Fingerprinting Properties., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20, https://doi.org/10.5194/egusphere-egu24-20, 2024.

Temporary Storage Areas (TSAs), such as bunds, offline ponds and leaky barriers represent a nature-based solution that can offer additional storage during storm events. They are designed to intercept and attenuate surface runoff, thereby addressing various catchment challenges, including flooding, water scarcity, and soil erosion. Soil infiltration is a key TSA outflow, particularly for more common small to medium storm events, meaning TSA functioning may vary between sites with different soil properties and be time-variable due to the dynamic nature of soil structure. The lack of understanding of TSA functioning in space and time represents a major knowledge gap and acts as a limiting factor for the widespread implementation of TSAs. To address these challenges, there is a need for a TSA analysis approach that allows for the systematic evaluation of TSA functioning.  The overall aim of this study was to enhance understanding of TSA functioning and explore variability in functioning with space and time. Specifically, the objectives were to: (i) develop a systematic data-based method for characterising the functioning of various TSA types; and (ii) assess the effect of spatial and temporal soil variability on TSA functioning and flood mitigation effectiveness.

Here we present the TSA Drainage Rate Analysis tool (TSA-DRA tool), a new data-based mechanistic approach that utilises only rainfall and water level to characterise drainage of individual TSAs. Results from a multi-site TSA assessment in the UK revealed time-variable functioning, especially at lower levels when soil infiltration is the dominant outflow. We explored this further by assessing changes in soil physical properties (bulk density, macroporosity and saturated hydraulic conductivity) at two TSA sites. These sites shared the same TSA type (bund) and had similar volumes (~250 m³) and soils (Cambisols). However, they differed in land use (winter wheat vs spring barley and blackcurrants) and TSA surface area (800 m² vs 2800 m²). Soil cores were taken across three spatial zones: (1) TSA active zone (<10% full) – inundated for the longest time; (2) full zone (>50% full) – active during large storms; and (3) Field zone – field control points outside the wetted footprint. This assessment was then repeated for significant temporal events e.g., post-harvest, growing season and post-flood. Results show significant soil structure variations over time and space, with degradation more pronounced in soils within the TSA wetted footprint due to inundation. While tillage effectively reset topsoil structure at one site, its impact was negligible at the other site due to variations in land management, coupled with high sedimentation post-flooding, altering near-surface soil texture. Results from a modelling exercise suggest that well-structured soils with higher infiltration rates can improve TSA effectiveness during a large storm event by reducing the volume and frequency of overflow compared to a degraded soil. Gaining insights into spatial and temporal variations in TSA functioning is crucial for optimising both current and future TSA designs and maintenance regimes.

How to cite: Roberts, M. T., Geris, J., Hallett, P. D., and Wilkinson, M. E.: Understanding spatial and temporal functioning of temporary storage areas to improve their flood mitigation effectiveness, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1585, https://doi.org/10.5194/egusphere-egu24-1585, 2024.

This study examined the sediment characteristics of areas where landslides occurred due to heavy rains between 2014 and 2019. A total of 5 types of geology in two geographic regions in Japan were examined using LiDAR LP topography data before and after the disasters occurred to estimate the changes in elevation. In addition, the volume of sediment runoff for each case was estimated for watershed areas ranging from 0.01 up to 0.1 km². The influence of geological differences on the sediment runoff volume within the basin using indicators such as the density of landslide occurrence, landslide volume, and watershed erosion intensity was also assessed. The results showed that, for all geology types, as the watershed area increases, the relief ratio decreases and the sediment runoff volume increases; however, the magnitude of this increase in sediment runoff volume differs depending on the underlying geology. In addition, the density of landslide occurrence was high in plutonic and metamorphic rocks. The landslide volume and the total eroded sediment volume within a watershed can be regressed using the linear equation y=ax. Since the average total eroded sediment volume within a watershed is approximately twice that of the landslide volume, there is a proportional relationship of 1:2. The relationship between the relief ratio and watershed erosion intensity shows that the watershed erosion intensity increases gradually as the relief ratio increases, and the rate of increase is larger in plutonic rocks (granite and granodiorite) than in the other groups. Metamorphic rocks had a relatively low watershed erosion intensity; these geological differences are reflected in differences in the degree of erosion of stream beds and banks by flood flows.

How to cite: Akita, H.: Comparison and analysis of the influence of geological differences on sediment runoff volumes from watersheds -case study of plutonic and metamorphic rocks in two sediment disasters in Japan-, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1808, https://doi.org/10.5194/egusphere-egu24-1808, 2024.

Several innovative techniques have been developed recently opening up new avenues to establish the assessment of sediment flux in the critical zone. These innovative techniques include the tracing or “fingerprinting” methods to identify the sources and quantify the dynamics of sediment and particle-bound contaminants. However, the use of these techniques is often associated with several methodological and statistical limitations, that are often reported although rarely addressed in the framework of concerted actions taken at the level of the international scientific community.

This presentation will present the main outcomes of the Thematic School organised in 2024 and the Scientific Meeting Days organised in 2022 and 2023 as a follow-up of a first training week organised in 2021 to bring together international experts working on these topics together. Based on the publication of an opinion paper (https://link.springer.com/article/10.1007/s11368-022-03203-1), new strategies to publish and disseminate sediment tracing databases will be presented. An example of formatted dataset will be given, with the objective to test research hypotheses based on multiple datasets adopting the same format of data/meta-data. Other perspectives regarding improvements of the sediment fingerprinting method in terms of modelling, tracer options and selection will also be presented.

How to cite: Evrard, O. and the TRACING Event organisers and participants: TRACING 2021-2024 – Feedback on international events to develop novel strategies of sediment tracing in catchments and river systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1817, https://doi.org/10.5194/egusphere-egu24-1817, 2024.

Soil erosion has on– and off-site detrimental effects, including decreased soil quality and sediment buildup in reservoirs. Predicting and monitoring soil erosion is challenging due to the spatio-temporal variation of its triggering factors. Therefore, developing and successfully implementing appropriate intervention measures requires a thorough understanding of its redistribution at the catchment scale. However, many previous soil erosion prediction models have been calibrated/validated based on sediment yield at catchment outlets. This approach does not provide any insight into the sources and sinks of erosion and deposition within the catchments. Furthermore, this approach has limited applicability in regions with no (limited) measured data. Therefore, exploring spatial patterns of erosion and deposition using the recent advances in remote sensing and GIS technologies is advisable. This research integrates the semi-distributed Unit Stream Erosion Deposition (USPED) model, and gully erosion threshold indices, described by stream power index (SPI) and topographic wetness index (TWI), to evaluate the sediment redistribution dynamics of a sub-humid catchment located in Omo-basin in southwestern Ethiopia. The catchment (~77 km²) has a rugged topography with an average slope of 35.8 %. It consists of four primary types of land use and cover (LUC): rangelands (20%), forest areas (19%), built-up areas (7%) and cultivated lands (54%). The (preliminary) results revealed that the gentle and mild slopes contribute more (53%) to the overall annual catchment soil loss (42.5 t.ha^-1) from the hillslope. This is because the sediment deposited in the downstream sinks remobilizes, shifting an erosion-limited to a transport-limited system. Moreover, the total contribution of rangelands and forest areas is comparable to that of cultivated lands. Therefore, by focusing our management efforts on these areas, instead of the steeper slopes, we can make a greater impact on the overall sustainability of the catchment.

How to cite: Yemane, H., Vermeulen, B., Grum, B., Baartman, J., Hoitink, T., and van der Ploeg, M.: Exploring the sediment redistribution dynamics of a data-scarce catchment in southwestern Ethiopia using the USPED model and gully erosion threshold indices, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3919, https://doi.org/10.5194/egusphere-egu24-3919, 2024.

Usual works for the reduction of the sediment volume transported by debris flows are the retention basins. Retention basins are usually built on the intermediate and low-sloping reaches of the debris-flow channels or at their end, where the terrain slope is usually not high. When the space required for trapping all the sediment volume is not available or the upper part of the basin must be protected deposition areas can be used. The deposition area is a retention basin without the downstream berm, to be placed in the high-sloping reach of a debris-flow channel. Therefore, it is proposed an approach for the progressive reduction of the sediment volume transported by debris flow: an in-series combination of deposition areas in the high-sloping reaches of the channel, and retention basins in the intermediate low-sloping reaches of the flow path.

An application of such approach is shown for the design of the control works on Ru Secco Creek at the purpose of defending the resort area and the village of San Vito di Cadore (Northeast Italian Alps).

How to cite: Gregoretti, C., Barbini, M., Bernard, M., Boreggio, M., Lopez, S., and Schiavo, M.: An approach for the reduction of the sediment volume transported by debris flow from the high-sloping reach of a debris-flow channel, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4719, https://doi.org/10.5194/egusphere-egu24-4719, 2024.

In this study, the variations of rainfall, river discharges and suspended sediment discharges were analyzed in the Chenyulan watershed in Nantou County, central Taiwan. The hydrological data, such as rainfall, daily discharges and daily suspended sediment discharges, was collected based on Neimaopu hydrology station during the period from 1972 to 2020. The yearly costs of structure conservation to prevent sediment disasters and slope hazard events were implemented in the watershed between 1999 and 2020 as well. The Rating Curve Method with the formula Q_s=aQ^b is adopted to estimate sediment discharges with the corresponding discharge events. The impact factors that caused the variation of discharges and suspended sediment discharges were also analyzed to provide the references for the influence of geological and hydrological changes on sediment yielded on slope and following suspended sediment discharges in the rivers in the watershed. The analyzed results show that the suspended sediment discharges in 1972-1989 are less than the average value in 1990-2009 at the same discharges. The suspended sediment discharges in 2010-2020 are gradually reverted to that in 1972-1989. The causes of decreasing the suspended sediment discharges in last decade are analyzed, including: 1. The variations of rainfall were gradually calmed in last decade; 2. the loose soil on slopes in the watershed caused by Chi-Chi earthquake became concreted with time; 3. the landslide and debris flow disasters obviously decreased in last decade and the soil yield from slopes has slowed down; 4. the local government involved a lot of money to build the conservation structures in upstream creeks to trap the loose soil and control the volume of sediments from flowing into rivers.

How to cite: Huang, W.-S., Chen, J.-C., Chien, K.-H., Lia, Y.-T., and Wu, F.: Impacts of rainfall variability on river discharges and suspended discharges : A Case Study in Chenyulan Watershed, Taiwan, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5507, https://doi.org/10.5194/egusphere-egu24-5507, 2024.

Impact of dam construction on suspended sediment load alteration

Zahra Karimidastenaei ^a*, Hamid Darabi ^b, Ali Torabi Haghighi ^a

^a Water, Energy and Environmental Engineering Research Unit, University of Oulu, P.O. Box 4300, FIN-90014 Oulu, Finland.

^bDepartment of Geosciences and Geography, University of Helsinki, Helsinki, Finland

*Corresponding author: Email: zahra.karimidastenaei@gmail.com

Abstract

Climate change and human activities have always impacted the fluvial processes, encompassing floods, soil erosion, sedimentation, and sediment transport in rivers, resulting in huge environmental concerns. Dynamics analysis of suspended sediment concentration (SSC) is a determining factor in the sediment budgets, and it has an important role in water resources management. In the current research, the relationship of the suspended sediment (SS) with precipitation (R) and flow discharge (Q) has been analyzed to assess the impact of Saveh Dam on the SSC during 1971-1982 and 1983-1994 as pre and 1995-2006 and 2007-2018 as post-impact periods in the Ghareh-chay basin, Iran. To quantify the spatio-temporal variation of SSC (due to climate change and anthropogenic activities such as dam construction and land use changes), a new measure Δα-based approach was introduced. The newly developed approach, referred to as the Δα-based method, was formulated by calculating the angle between (or the change in the slope of) the optimal Precipitation-Sediment (P-S) and Flow-Sediment (F-S) fit lines. This calculation is conducted spatially, encompassing both upstream and downstream locations, and temporally, by comparing data from different periods. The findings showed that Δα for the Precipitation-Sediment (P-S) relationship between upstream and downstream increased significantly after the Saveh dam commissioning. Initially, Δα was measured at 2.69 degrees and 1.35 degrees for the two pre-impact periods upstream and downstream, respectively. However, these values rose to 5.65 degrees and 9.39 degrees in the corresponding post-impact periods. Based on these results, it is evident that the notable changes in Δα for the Precipitation-Sediment relationship between upstream and downstream indicate the dam's impact on the Suspended Sediment Concentration (SSC) patterns in the Ghareh-chay river. The relatively short distance between the upstream and downstream gauge stations further supports the conclusion that these observed changes in Δα are directly attributable to the dam's influence, significantly altering sediment dynamics in the river system.

Keywords: Saveh dam; dynamics analysis; pre- and post-impacted; quantitative approach, sediment rating curve

Fig. 1. Location of the study area

How to cite: Karimidastenaei, Z., Darabi, H., and Torabi Haghighi, A.: Impact of dam construction on suspended sediment load alteration, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5559, https://doi.org/10.5194/egusphere-egu24-5559, 2024.

The measurement of river bed grain size has become an integral aspect of fieldwork in river geomorphology and regional ecology. Over the past years, various authors have proposed remote sensing methodologies to assess grain size based on ground and aerial images. With the burgeoning applications of small unmanned aerial systems (SUAS) in geomorphology, there is a burgeoning interest in leveraging these remote sensing granulometry methods for SUAS imagery. However, a dearth of studies exists that systematically investigate spatially consecutive images yielding grading curves or specifications over extensive areas within mountainous watersheds.

This study focuses on the granulometry of the mountainous watershed in Val Camonica, located in northern Italy, employing a drone for initial photographic documentation. The study incorporates the BaseGrain software for importing drone spatially consecutive images and extracting granulation curves from the photographed areas. Additionally, the study encompasses the utilization of Structure-from-Motion (SfM) photogrammetry within a Ground Control Points (GCP) workflow to scale the drone-acquired photos. The precision of this scaling is systematically validated by comparing photos with scaling images including meter using BaseGrain software. The precision of AGISOFT software, employed in the SfM-photogrammetry process, is also critically evaluated by itself with different numbers of benchmarks.

Results indicate that, despite the non-professional nature of the instrumentation, the acquisition of high-resolution images is feasible. These images enable the generation of Digital Elevation Models (DEMs) with accuracies ranging between 2 and 3 cm, contingent upon the number of ground control points. The granulation curve, extracted through BaseGrain, exhibits acceptable accuracy within meter-scale resolution. This research contributes valuable insights into the potential of SUAS-based remote sensing granulometry for mountainous watersheds and underscores the importance of methodological precision for reliable results in river geomorphology studies.

How to cite: Benetti, M., Heidarian, P., Bonomelli, R., and Pilotti, M.: Exploring Remote Sensing Methodologies for River Bed Grain Size: Insights from a Mountainous Watershed Study in Val Camonica, Italy, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5752, https://doi.org/10.5194/egusphere-egu24-5752, 2024.

To mitigate riverbed erosion both longitudinally and transversely, control water flow, and stabilize riverbanks, the use of groundsills has become a widely adopted engineering method. For large conservation areas, using a series of groundsills is standard practice. However, the sediment transport in rivers is a dynamic process, and the implementation of series groundsills can cause discontinuities in the longitudinal corridor of the river, leading to damage to the ecological environment and landscape. Although there is considerable consensus on various aspects of series of groundsills, current research primarily focuses on the influence of the configuration of groundsills (such as height and width) on sediment downstream. Therefore, this project aims to estimate the trends in sediment transport through scaled experiments and numerical simulations. Results shown that according to the analysis results, neither the Q5 nor Q95 criteria are met in the proposed plan for the complete removal of the groundsills. This project believes that the complete removal of the groundsills may have a drastic impact on the environment, potentially leading to unstable conditions, and thus requires careful evaluation. The design of openings in the groundsills is an effective ecological adjustment project. Regarding the design of the opening height, this project suggests considering two factors: one is to reduce the similar damming effect caused by lowering the elevation, and the other is the gathering of water flow. It is a trade-off between these two factors. Increasing the depth of the opening may benefit the ecology but could lead to unintended erosion due to concentrated water flow, and vice versa.According to the analysis results, neither the Q5 nor Q95 criteria are met in the proposed plan for the complete removal of the fixed-bed structure. This project believes that the complete removal of the fixed-bed structure may have a drastic impact on the environment, potentially leading to unstable conditions, and thus requires careful evaluation. The design of openings in the fixed-bed structure is an effective ecological adjustment project. Regarding the design of the opening height, this project suggests considering two factors: one is to reduce the similar damming effect caused by lowering the elevation, and the other is the gathering of water flow. It is a trade-off between these two factors. Increasing the depth of the opening may benefit the ecology but could lead to unintended erosion due to concentrated water flow, and vice versa. he proposed plans can optimize benefits for both upstream and downstream water conservation, and protect downstream objectives by managing sediment transport.

Keywords: series groundsill, ecology, sustainable management, sediment transport

How to cite: Lin, P., Hsieh, T., Liao, K., Wei, K., and Lin, G.: Impact Analysis of Series of Groundsills on the Fluvial Stability and Geomorpholog, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7560, https://doi.org/10.5194/egusphere-egu24-7560, 2024.

Torrential dynamic is a complex combination of natural processes along a mountain watercourse, including sediment deposition and erosion that cause cross-section occlusions and streambank failure, respectively. Thus, monitoring and managing sediments are fundamental activities for the maintenance in mountain watersheds. To regulate the sediment transport, a common countermeasure is the check dam, designed to control the sediment movement along the watercourse (Piton et al., 2017). Building check dams is complex and expensive, especially in mountain watercourse. These structures largely modify the surrounding environment and landscape; however, if well designed, check dams are very effective solutions to mitigate the potential losses due to flood, debris flood, and debris flow.

This study presents the monitoring of a stretch of a mountain watercourse over several years in an Alpine environment. The observed dominant process was the sediment deposition that has been countered by the construction of a slot check dam. The torrential dynamic has been strongly influenced by this in-channel structure, exacerbating the change of cross-sectional and longitudinal profiles (width and depth of the cross-sections, longitudinal profile, and bed granulometry) not only in proximity of the structure, but also along the observed overall stretch (downstream and upstream). The monitoring consists in measuring the hydrological response during rainfall events and assessing the geomorphic change using digital elevation models differencing (2010, 2014, 2021, 2023). The last topographic surveys were conducted immediately after the construction of the slot check dam and immediately after the first severe debris flood occurred several months later.

The results of monitoring show a clear geomorphic evolution along the observed stretch, contrary to the previously detected tendency of sediment dynamics and, moreover, a different hydrological response at downstream of the structure. As expected, sediments were trapped upstream of the structure, whereas a severe erosion removed the armoring layer bringing to light several bed sills at downstream.

This study underlines how artificial works have a spatially distributed effects on geomorphological change, on hydraulic behaviour, and in some cases on the flood hazards (also far from the structure). Thus, the prediction of geomorphological change, even if qualitative, is extremely important to improve the effectiveness of the check dam in managing sediment dynamics. In addition, sharing this information is essential to support designers (showing practical examples) in planning works not only focusing on the structural and hydraulic perspectives, but also from a geomorphological point of view, which is often neglected.

How to cite: Cislaghi, A., Bellingeri, D., Sacchetti, V., Morlotti, E., and Bischetti, G. B.: Impacts of check dams: a monitoring experience along a mountain watercourse, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7827, https://doi.org/10.5194/egusphere-egu24-7827, 2024.

Austria has a wide variety of protection structures at different condition levels due to the long tradition of torrent control works in the Austrian Alps. This has resulted in a large stock of protection structures and load models. In order to standardise the design of technical structures based on the Eurocode, including torrential processes, snow avalanches and rock fall, an interdisciplinary working group (ON-K-256) was established. The standardisation for torrential processes covers the definition and classification, the impact on structures, the design of structures, and the operation, monitoring and maintenance. These parts are based on and interact with EN 1990 (the basis of structural design), EN 1992-1-1 (the design of concrete structures), EN 1997-7 (geotechnical design) and the related documents for the Austrian national specifications. For torrential mass wasting processes with high variability in the concentration of solids, modern protection concepts are scenario-oriented. To optimize the mitigation measures for a multi-stage system, a functional chain must be implemented. This chain should have different structures to perform various functions such as dosing, filtering, and energy dissipation. When designing these torrential mitigation structures, it is necessary to simplify the model parameters, stress model, and load distribution. For debris flows, a standardized stress model combines the static and dynamic loads of debris flow impact on structures. This model was calibrated using available impact measurements of real debris flows and is in good agreement with common engineering design methods in Austria for debris flow impact on torrential barriers. The proposed method enables practitioners to design debris flow countermeasures with limited data availability.

How to cite: Nagl, G., Hübl, J., and Suda, J.: The new Austrian standard ÖNORM B4800 for torrent control work, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8068, https://doi.org/10.5194/egusphere-egu24-8068, 2024.

Monsoon-induced floods have played a pivotal role in shaping the fortunes of Asian civilizations and communities over the millennia, and their far-reaching consequences persist to this day. This study delves into the floodplain east of Nan ancient city, a city during Lan Na period in northern Thailand dating back to the 13^th century AD. Our primary objective was to unravel the source direction of a catastrophic flood event in 1818 AD, which ultimately led to the city's relocation. Our sedimentological analyses revealed a diverse range of deposition. An innovative provenance study using mid-infrared spectroscopy (MIRS), conducted for the first time in this region, indicated a significant contribution from eastern tributaries not from the Nan River. Only two of the nine sediment cores (WTR and HH2) presented evidence of Nan River sediment. Optically stimulated luminescence (OSL) dating revealed a striking pattern: modern floods dominated the shallow depths (ca. 0-1.10 m) of all cores, while deeper layers exhibited unexpectedly older ages, exceeding 11,000 years. This finding aligns with climate data from multiple proxies, suggesting that Nan ancient city, akin to neighboring e.g. Kingdom of Angkor, endured a dry period. Based on these comprehensive findings, we postulate that the 1818 AD flood catastrophe originated from the east. The deluge may have been triggered by rainfall during an extended dry spell, when the parched and compacted soil's permeability was severely diminished. This sudden surge of water swiftly transported the sediment, ultimately inundating and devastating the city. The insights gained from this study are a reminder of the profound impact of monsoon-related floods on human settlements in Asia. By understanding the conceptions between sedimentology, provenance, and climate, we can better comprehend the historical and ongoing challenges posed by these natural disasters and advance strategies for sustainable development in vulnerable regions.

Keywords: flood sediment, monsoon, Southeast Asia,  provenance analysis, OSL dating, Lan Na, Nan, Thailand

How to cite: Srisunthon, P., Berger, A., Fuelling, A., Abdulkarim, M., Ertlen, D., Mueller, D., Wilk, J., Reubold, M., and Preusser, F.: Reconstructing the Flood History of Nan Ancient City: Insights from Sedimentary Analysis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8164, https://doi.org/10.5194/egusphere-egu24-8164, 2024.

In mountain basins, the predominant approach to control the supply and transport of large volumes of sediment involves the installation of hydraulic structures within the channel network. While torrent control works are fundamental in reducing flash flood impacts, their effectiveness during time need regular monitoring and maintenance. However, few studies have proposed a workflow based on simple factors and criteria collected in the field to prioritize management interventions of torrent control works in a mountain basin. In this work, the aims are to assess the effectiveness of the hydraulic structures and to quantify their impact on sediment continuity in the Vegliato mountain basin (Italy), affected by a flash flood event occurred on the 30^th July 2021. First, rainfall data from 2019 to 2022 are analyzed to detect and characterize the event that caused the flash flood. The assessment of post-event status and functionality of the control works is done using a novel Maintenance Priority index (MPi), distinguishing the structures that no longer fulfil their role and providing an overview on the maintenance and re-planning of the management system. These results integrate the analysis of multi-temporal High Resolution Topography (HRT) data deriving from LiDAR surveys. DEMs of Difference (DoDs) are generated to map the geomorphic changes occurred during the event, quantifying the sediment fluxes impacting on the control works and viceversa. The role of torrent control works is also analyzed in terms of continuity of the sediment cascade applying a novel parameter, the Sediment (dis)Continuity Ratio (SCR), which assesses the capability of the torrent control works system in intercepting and storing a sediment mass fraction constituting the cascade (obtained by DoD) and identifies the hydraulic structures that contribute or limit the sediment (dis)continuity along the channel network.

The application of the MPi indicates that the 16% of the control works should be given the highest maintenance priority (MPi = 1). The 45% of the hydraulic structures exhibit 0.63 ≤ MPi ≤ 0.88 and are in need of intervention to ensure the durability of the structures themselves. On the other hand, 12% of the control works require re-planning operations (0.25 ≤ MPi ≤ 0.50) due to their good structural condition but low functionality. Eventually, the 25% of the structures show MPi = 0 and are in the lowest range of priority for the interventions. These results were also corroborated by the DoD results, which supported the MPi. The analysis of the SCR shows how several torrent control works, especially the ones located in the upper part of the catchment, promote continuity (SCR from -100 to -0.1). On the other hand, several structures in the middle part of the main channel show positive SCR values, therefore promoting discontinuity. The highest values of SCR are found in the downstream and wider part of the main channel.

Finally, the workflow composed of different methodologies adopted in this work provides a detailed overview of the interaction between sediment dynamics and torrent control works and represent a useful tool to develop effective management decisions and plans.

How to cite: Piccinin, F., Martini, L., Cucchiaro, S., Pellegrini, G., Maset, E., Beinat, A., Baggio, T., Cazorzi, F., and Picco, L.: Assessment of flash flood impacts in a mountain basin: an integrated approach for the management of channel control works, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8675, https://doi.org/10.5194/egusphere-egu24-8675, 2024.

Beyond land-use alterations at the catchment scale, numerous mountain catchments across Europe have experienced significant morphological changes and shifts in sediment transport dynamics over the past two centuries, largely attributable to the implementation of torrent control structures. A notable example is the mountainous part of the Czech Carpathians, where a comprehensive sediment management regime was introduced at the turn of the 19th and 20th centuries. This approach, based on methodologies established in the Austrian Alps, encompassed the installation of check dams and artificial bank stabilizations. Such practices have remained predominant in these areas, with certain catchments smaller than 25 km² exhibiting substantial portions of their stream lengths stabilized through sequences of consolidation check dams, bed sills, and riprap bank stabilizations.

However, it is crucial to consider the distinct nature of external factors influencing rainfall-runoff processes and sediment supply in the 19th century. This period was marked by the end of the Little Ice Age and a higher prevalence of deforested areas, linked with active gully development. Given the contemporary context of extensive reforestation and subtly altered hydroclimatic conditions, the appropriateness of continuing such 'hard and intensive' management strategies for local streams warrants reassessment.

Consequently, a sediment deficit in both mountain channels and foothill gravel-bed rivers has been observed. It resulted in channel transformation with sediment coarsening, the loss of gravel bars (as vital habitats), and, in some instances, channel incision into the bedrock. This situation necessitates a reconsideration of sediment-control strategies within the frameworks of fluvial continuum and sediment (dis)connectivity, particularly since these headwaters function as primary sediment sources. Without modifying these management approaches, enhancing the hydromorphological state of streams and rivers in the Czech Carpathians remains a formidable challenge.

How to cite: Galia, T., Škarpich, V., and Macurová, T.: (Dis)connected mountain headwaters: advocating for a paradigm shift in sediment management strategies, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9330, https://doi.org/10.5194/egusphere-egu24-9330, 2024.

In this study, we quantify the spatial variation in sediment generation for the c. 12 km² large Gürbe catchment situated at the northern margin of the Swiss Alps. We particularly trace the sediment transfer from the hillslope to the channel network in the headwaters, and finally to the depositional fan at the downstream end of the catchment. Mapping shows that sediment production in the Gürbe catchment occurs through three primary mechanisms: (1) overland flow erosion generating sand and silt, contributing to the generation of suspension loads; (2) shallow and deep-seated landslides linked to the main channel, both supplying a mixture of gravel, boulders, and silt/sand during floods, thus generating sediment for both the bedload and suspension load of the Gürbe River; and (3) incision of the river into glacial till in the upper headwaters and into landslides farther downstream. The bedrock of the Gürbe catchment comprises Molasse, Flysch, and Quaternary deposits, posing challenges in tracing the origin of the material and estimating the relative importance of the various processes for sediment generation.  However, previous research has shown that the cosmogenic ¹⁰Be concentration can differ for various sediment sources (Cruz Nunes et al. 2015; e.g.). Therefore, we measured ¹⁰Be concentrations in the sand fraction (0.25 – 2 mm) in the main channel and in the tributaries, aiming to capture suspension load signals generated through overland flow erosion and landslides. As a novel approach, we also determined the bulk ¹⁰Be concentration of gravels (2 – 10 cm) collected from the same sampling locations in the Gürbe channel, in the three tributaries as well as from the landslide tongues reaching into the Gürbe. The results point to three different conclusions: First, there exists a clear difference between the signals measured in the sand fraction and the gravel samples. In particular, the ¹⁰Be concentrations in the sand fraction are two to four times higher than those measured in the gravel at the same sites. This grain size dependence aligns with previous findings by Puchol et al. (2014). Second, the sand samples in the main channel show a downstream decrease in ¹⁰Be concentration, thereby reflecting the supply of material from the tributaries and particularly from the landslides with low ¹⁰Be concentrations. Third, bulk gravel samples reveal a larger variability in ¹⁰Be concentrations than the sand samples at the same locations. This suggests that the supply and downstream transport of the coarse-grained bedload material occurs more episodic than the generation and transfer of the suspension load. 

REFERENCES 

Cruz Nunes, F., Delunel, R., Schlunegger, F., Akçar, N., & Kubik, P. (2015): Bedrock bedding, landsliding and erosional budgets in the Central European Alps. Terra Nova, 27(5), 370-378.

Puchol, Nicolas; Lavé, Jérôme; Lupker, Maarten; Blard, Pierre-Henri; Gallo, Florian; France-Lanord, Christian (2014): Grain-size dependent concentration of cosmogenic 10Be and erosion dynamics in a landslide-dominated Himalayan watershed. In: Geomorphology 224, S. 55–68.

How to cite: Schmidt, C., Mair, D., Schlunegger, F., McArdell, B., Christl, M., and Akçar, N.: Quantifying Sediment Dynamics in an Alpine River Catchment using a 10Be Tracing Method , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9807, https://doi.org/10.5194/egusphere-egu24-9807, 2024.

Land-use specific sediment source apportionment using compound specific isotopic tracers occurs with challenges from both contributions from aquatic  and particulate organic matter sources. Additionally, compound specific tracers have often occurred with co-linearity. Challenging our current understanding of erosion processes, previous studies using compound-specific isotopic tracers regularly indicate forests as the dominant source of sediment. We hypothesized that this estimation may be attributed to misclassifying particulate organic matter as a sediment contribution from forests.

This study is based in Lake Baldegg (Lucerne, Switzerland) and utilizes the δ¹³C values of lignin-derived methoxy groups and alkane average chain length as an additional land-use-specific tracer to δ13C fatty acids. Three Suess corrections using different tracer residence times are applied to constrain the changing δ¹³C values of CO2 in the atmosphere over the last 130 years. To identify changes in sediment sources over the last 130 years, contributions of particulate organic matter are determined, and subsequently removed to apportion only the mineral associated soil fraction. To determine the confidence which can be applied to the model’s output, the model's performance is evaluated with 300 mathematical mixtures. The potential misclassification of forest contributions is investigated by merging particulate organic matter and forest sources to simulate tracers which are unable to discriminate between these two sources.

The incorporation of δ¹³C values of lignin methoxy groups and alkane average chain length as additional tracers successfully expands the problematic one-dimensional mixing line.  Mathematical mixtures demonstrate the improvement of the model’s performance when using both the average chain length and δ13C values of lignin-derived methoxy groups as an additional tracer. Furthermore, they also demonstrate an underestimation of arable contribution. Changes in dominant sediment sources (Forest: pre-1990, Pasture: 1910-1940, Arable: post-1940) highlight the influence of policy-induced land-use changes. Additionally, the study reveals a 37% overestimation of forest contributions to the sediment core due to the inability to discriminate between particulate organic matter and forest sources.

The use of δ¹³C values of lignin methoxy groups as an additional tracer enables the identification of critical points in the 130-year sediment history of Lake Baldegg. We emphasize the importance of incorporating multiple Suess corrections to constrain the effect of multiple turnover times of tracers. While merging forest and particulate organic matter sources did not alter the dominant source over the last 130 years, it highlighted the need of separating these sources for more accurate apportionment. The study contributes valuable insights to sediment dynamics and land-use impacts, offering guidance for environmental management strategies.

How to cite: Cox, T., Laceby, P., Greule, M., Keppler, F., and Alewell, C.: Using stable carbon isotopes of lignin derived methoxy groups to investigate the impact of historical land use change on sediment/particulate matter dynamics , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10471, https://doi.org/10.5194/egusphere-egu24-10471, 2024.

Hydrological and sediment transport regime are important in water resource management. Aim of this study is to identify the flow regime and the suspended sediment transport in a Mediterranean River Basin. Precipitation, temperature, soil, land use, discharges and suspended sediment concentration are used to quantify runoff and sediment yields at daily scales. WASA-SED (Water Availability in Semi-Arid environments – SEDiments) a spatially semi distributed model it is developed to simulate the flow and sediment transport in Seman Basin. Sediment deposits in Seman Basin contribute to a significant annual loss in the water storage capacity of the dams. Runoff and suspended sediments in Mediterranean hill slopes are closely related to rainfall intensities and land surface cover. This study gives a valuable approach in improving the prediction of flow and sediment transport in Mediterranean River Basin.

Keywords:
Flow, Sediment transport, WASA-SED, Mediterranean River Basin

How to cite: Doko, A., Bronstert, A., and Francke, T.: Hydrological and Sediment Transport Regime on Rivers in the Balkans: The Case of the Seman River in Albania, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16053, https://doi.org/10.5194/egusphere-egu24-16053, 2024.

One of the main impacts of water erosion within a watershed is the downstream deposition of sediments in watercourses and decrease in water quality, esigning and implementing effective soil and water conservation practices to address these impacts requires a soil conservation practices. Increasingly, researchers are using sediment source fingerprinting methods which use physical, biological, and geochemical attributes of the soil and sediments as tracers (Tiecher et al., 2015). Identifying sediment sources enables targeted corrective measures, but tracer selection and fingerprinting feasibility are ongoing debates among experts (Lizaga et al., 2020; Owens et al., 2022).

This study focuses on identifying sediment sources to develop erosion mitigation plans in a 33.3 km² rural river basin, in southern Brazil, crucial for supplying the municipality of Pelotas. Three primary sediment sources were identified: annual crops, perennial forage (pastures), and gutters (river channels). Samples were collected from the surface horizon (0-20 cm) of agricultural land and perennial pastures. Gutter samples were collected from the underground horizon, where active erosion processes were taking place. In total, 116 source samples were obtained. Nine sediment samples were collected from six sites across the study area every two months during 2021-2022, forming three collections for each sub-area of the river basin (A1, A2, and A3). Traditional fingerprinting methods, utilizing geochemical tracers, total organic carbon, and color coefficient tracers in the visible spectrum, were employed to analyze the soil of the contributing area and the sediments. The FingerPro (v1.1; Lizaga, 2018) mixture model was applied to evaluate the contributions of sediment sources to the collected sediment.

This communication presents preliminary results of 37 tracers: 22 geochemical elements, 14 color coefficients, and total organic carbon. Data processing, using FingerPro, was conducted separately by sub-area and sediment collection. Tracer selection involved a-two sequential statistical tests: 1) Kruskal-Wallis (KW) selects tracers with significant differences between at least two sources and 2) Discriminant Function Analysis (DFA) selects optimal tracers that effectively discriminate between the three sediment sources.

The results obtained demonstrated that the selected tracers for each sub-area varied considerably. For example, the tracer selection procedure for sub-area A1 resulted only in total organic carbon as a viable tracer while the number tracers selected for the other two sub-areas were seven and five, for A2 and A3, respectively. Notably, the varying sets of tracers being selected for each sub-area indicate that the heterogeneity in soil properties is an important consideration in sediment source fingerprinting studies. Combining samples from the whole river basin may distort sediment dynamics. Tailored approaches are crucial for accurate understanding and management.

Acknowledgements

This study was made possible by the generous support of Brazil-CAPES through a doctoral scholarship (Finance Code 001).

References

Lizaga et al. 2020. Consensus ranking as a method to identify non-conservative and dissenting tracers in fingerprinting studies

Lizaga. 2018. fingerPro 1.1.

Owens, P. N. 2022. Sediment source fingerprinting: are we going in the right direction?.

Tiecher et al. 2015. Combining visible-based-color parameters and geochemical tracers to improve sediment source discrimination and apportionment 

How to cite: Araujo, M., Guzmán, G., Gómez, J. A., Koiter, A., Nachtigall, S., and Miguel, P.: Sediment Source Identification in a Southern Brazilian Watershed: Utilizing Geochemical Properties and Spectral Signatures with Mixing Models, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16690, https://doi.org/10.5194/egusphere-egu24-16690, 2024.

Most of the total sediment load transported in river systems is carried in suspension. Therefore, if we are to reduce soil erosion and sediment export, it is essential to determine suspended sediment sources and the drivers of its mobilisation into the river network. In this study, we combined the monitoring of suspended sediment fluxes and the sediment fingerprinting approach to test if pre-event conditions and rainfall-runoff characteristics drive suspended sediment source variability in catchments under a semi-oceanic climate. The sedimentological response to storm runoff events was studied in seven nested sub-catchments of the Attert River basin (0.4 - 245 km²), which have contrasting geological bedrock (sandstone, marls and shale) and land uses (forest, cropland and grassland). We collected stream water samples during storm runoff events (~30 events per catchment) using automatic water samplers to measure suspended sediment fluxes. In parallel, time-integrated suspended sediment and sediment sources samples (i.e., from different land use types) were collected and analysed in the laboratory (geochemistry, colour and organic properties) to determine the sediment origin using the sediment fingerprinting approach. Each sampled event was parameterized to describe rainfall, runoff, sediment transport and the relative contribution of each land use type to the sampled suspended sediment. Next, we assessed the relationships between variables. We found higher significant correlations between suspended sediment loads and runoff parameters (i.e., peak discharge and event runoff) than between suspended sediment loads and rainfall parameters (i.e., event precipitation, antecedent rainfall, and maximum rainfall intensity). Peak discharge for single events was found to be the best predictor of sediment loads in the studied catchments. We show that most events exhibit clockwise hysteretic loops between discharge and suspended sediment concentration in all studied catchments. We attribute this finding to the erosion or remobilization of sediment previously deposited on the channel bed or an adjacent area. During most of these events with clockwise hysteretic loops, sediment source apportionment presented a consistent pattern.

How to cite: Martínez-Carreras, N., Iffly, J. F., and Pfister, L.: Pre-event conditions and rainfall–runoff characteristics drive suspended sediment source variability, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16692, https://doi.org/10.5194/egusphere-egu24-16692, 2024.

In the context of soil erosion modeling, coarse-grained sediments present considerable challenges, particularly concerning sediment production and quantification. This study proposes a module-based quantification approach that integrates different coarse-grained production processes, where one of the main outputs is the source area delimitation and the quantification of mobilizable sediment.

The present study focuses on analyzing shallow landslides and various scenarios of sediment transport to the nearest fluvial system, by implementing the newly developed “Random Connect” code. This code calculates the accumulated volume that travels from the source areas into the fluvial system based on the connectivity index. The chosen case study is the Saldes River basin in the Pyrenees (Spain) The outlet point of this basin is La Baells water reservoir, presently facing siltation challenges arising from sediment transport across the entire drainage area. Reported by CEDEX (2002), the sediment yield delivered to a La Baells Reservoir from the entire drainage area was 4.54 Mg ha⁻¹yr⁻¹ in 2002. In this sense, this water reservoir is utilized for calibrating and validating our model. The quantification of sediment in water reservoirs does not allow to separate the contributions of the different erosive processes at the basin, thus highlighting the importance of the study of the river section to better understand the sediment production.

For model calibration, field surveys were conducted to ascertain the connectivity index to the main river, identify (dis)connectivity factors, and measure fluvial and sediment grain characteristics. Comparing model output with field data enables determination of sediment transport potential and the maximum sediment quantity that can reach the main river. Depending on the connectivity threshold, the results of sediment reaching the main river for a critical rainfall event can vary between 250000 to 10000 m³.

Assessing sediment at the river cross-section helps in defining the principal coarse-grained production phenomena, such as shallow landslides, rock falls and debris flows. Grain characterization of sediment is necessary to study sediment mobilization through a hydrological-driven module. The main objective is to track coarse-grained sediment until it reaches the water reservoir and identify the meteorological and physical factors that trigger the process.

A historical baseline of sediment production has been determined for the Saldes River basin, based on historical landslide inventories, previous triggering events, and meteorological scenarios for the current climate. The assessment considers the impact of climate change in Spain at different timelines based on return periods. The rate of sediment production is determined by analyzing critical climate change scenarios, resulting in values below and above the baseline. This analysis places special emphasis on extreme climate events and the projection of mean annual precipitation.

How to cite: Rodriguez, S., Hürlimann, M., Medina, V., Torra, O., Oorthuis, R., and Puig Polo, C.: Sediment contribution of shallow landslides and flux connectivity of transfer paths in mountainous areas under climate change projections. A case study for the Saldes River basin (Pyrenees, Spain), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17307, https://doi.org/10.5194/egusphere-egu24-17307, 2024.

Debris flows are fast-moving masses of rock, soil, and water, which occur in mountain areas all over the world. Debris flows achieve maximum discharges that are many times greater than those associated with floods and are therefore often hazardous to people and infrastructure. Contrary to the general expectations that climate change will increase the magnitude and frequency of the debris flows, recent assessments have shown that under certain conditions future climate may increase the sediment transport capacity, but could also favor a reduction of the sediment supply and, therefore, reduce debris-flow activity.  The impact of glacier retreat together with future climate conditions on debris-flow catchments is not yet fully understood, but it is expected to increase due to uncovered glacial till, increased hillslope instabilities and an increase in peak rainfall intensities. We aim to quantify the effect of the changes in water availability (changes in precipitation regime, but also glacier meltwater) together with the subsequent landscape changes in climatically contrasting catchments in High Mountain Asia (HMA) on the frequency and magnitude of debris flows. We address it by further extending the sediment cascade model (SedCas), expanding the available hydrological response units to bedrock, vegetated and glaciated parts of the catchment. We further investigate (1) how sediment yield and debris flow magnitude-frequency change over time, and (2) how deglaciation and catchment greening (changes of land cover) affect debris flow activity for different climate regions across High Mountain Asia. We find that in the case study of sediment-unlimited catchments, from 1950 to 2022, glacier retreat increases the water supply. That, in combination with the warming temperatures (and therefore the change in the partitioning of the solid and liquid precipitation) and the decrease in number of extreme precipitation events, results in a decrease in the debris-flow activity. These preliminary results show that changes are not consistent across HMA and highly depend on the climatic regime and elevation. Our findings shed light on the debris flow and flood hazard in the data-scarce areas of HMA and highlight the importance of considering regional climate conditions for hazard assessment in addition to region-wide estimation of glacier retreat. The future development will investigate the sediment-limited conditions. 

How to cite: Bazilova, V., Duurkoop, L., Hirschberg, J., de Haas, T., and Immerzeel, W.: Deglaciation and debris flow dynamics: how does the glacier retreat affect debris flow activity in High Mountain Asia? , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20102, https://doi.org/10.5194/egusphere-egu24-20102, 2024.

Faced with a decline in water resources due to precipitation reduction and variability, it is fundamental to identify potential natural "reservoirs" and quantify their water retention capacity. This study examined approaches to estimate the water content rapidly and systematically in the sediment upstream of check dams at different scales, even with limited input data.

The study was conducted in the northern part of Tuscany, with a specific focus on the Casentino Valley. After gathering the necessary databases and information, an estimation model was developed using QGIS Model Designer, and geophysical surveys were performed using Electrical Resistivity Tomography (ERT).

The QGIS-based model relies on limited input data, including the geographical positioning of weirs, the hydrographic network, and a Digital Terrain Model (DTM) of the study area. This method provides useful initial approximate estimates of the water resources in the study area. The ERT surveys revealed varying patterns depending on the lithology of different areas, but a clear discontinuity between the sediment wedge and the original riverbed was observed, confirming the effectiveness of this tool in analyzing each individual structure. With the data obtained through the databases, it was also possible to conduct an analysis on the relationship between the original slope and the compensation slope of sediment wedges, and the distance between check dams located on the same river reach.

In the perspective of utilizing these natural reservoirs, possible maintenance interventions are proposed, especially on the existing spillways, to make a portion of the available water usable, accompanied by an assessment of potential implications. In the future, implementing the outlined procedures and integrating them with other tools could provide support for evaluating and utilizing these "hidden water resources."

How to cite: Preti, F., Pini, S., Cassiani, G., Dani, A., Giambastiani, Y., Peruzzo, L., and Piemontese, L.: Accumulation of water and sediments upstream of Tuscan check dams, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20399, https://doi.org/10.5194/egusphere-egu24-20399, 2024.

Sediment fingerprinting has become a key tool to identify and quantify sediment sources within a catchment. The technique involves statistical testing of a range of properties of source materials to identify a set of tracers that can effectively discriminate between different potential sources before estimating the source contributions with unmixing models. However, despite its increasing popularity among researchers, there is a lack of standardized procedures for tracer selection, which is crucial to estimating a reliable contribution of sediment sources. The most widespread methodology consisted of an initial mass conservation test, usually termed range test (RT), followed by the use of Kruskal-Wallis (KW) and discriminant function analysis (DFA) tests. However, KW and DFA even though identifies the best combination of tracers that provide the maximum discrimination between sources, do not incorporate the information of the sediment mixtures in the analysis. Novel methods highlight the importance of selecting the right tracers for each individual mixture and avoid the inclusion of tracers out of consensus or with non-conservative behavior by using consensus ranking (CR) and consistent tracer selection (CTS) methods. This contribution addresses the role of selecting appropriate tracers, demonstrating their impact on the results of the unmixing model. The main objectives are to emphasize the importance of considering the information provided by the sediment mixture in the selection of tracers and to pay attention to the impact of having sediment mixtures with values below the detection limit of the tracer being selected for source discrimination. A set of experimental and real sediment mixtures were selected to explore the different tracer selection methods, comparing the tracers selected and the contribution of sources obtained using the FingerPro unmixing model. We present the results of rigorously testing methodologies with the aim of understanding and assessing the suitability of each tracer selection method to select a combination of statistical and process-based criteria to select appropriate sediment properties for the unmixing models. Our findings highlight the importance of considering the information on the sediment mixture information for the selection of potential tracers, an aspect often neglected by conventional methods. This oversight can result in biased findings due to the use of tracers that are either not coherent or not conservative.

How to cite: Gaspar, L., Latorre, B., Lizaga, I., and Navas, A.: Advancing sediment fingerprinting techniques: The importance of considering sediment mixtures data in tracer selection, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20482, https://doi.org/10.5194/egusphere-egu24-20482, 2024.

Various sediment-related disasters such as flash floods, debris flows and landslides can occur in an alpine torrential catchment area. To protect infrastructure and human life, various structural and non-structural (grey, green and hybrid infrastructure) protection measures can be used to mitigate torrential risks. An overview is given of the protective measures constructed near the Krvavec ski resort in north-western Slovenia (Central Europe). In May 2018, an extreme debris flood occurred in this area, causing considerable economic damage. After the event in May 2018, various field investigations (e.g. geological and topographical surveys) and modeling applications (e.g. hydrological modeling, debris flow) were carried out to prepare the necessary input data for the design of protective measures against such disasters in the future — due to climate change, further disasters are expected in this torrential catchment area. Compensatory measures include the engineering works of local streams, the construction of a large silt check dam for sediment retention, the construction of several smaller retention dams and the construction of 16 flexible net barriers with an estimated retention volume of ~8000 m3 to control erosion. A comprehensive monitoring system was also set up in the study area to observe and monitor potential future extreme events. This monitoring system includes measurements of corrosion of flexible nets, estimation of concrete abrasion on retention dams, regular geodetic surveys with small drones (UAV) and hydro-meteorological measurements with rain gauges and water level sensors. The recent extreme floods of August 2023 also hit this part of Slovenia, and this combination of technical countermeasures withstood the event and prevented large amounts of coarse debris from being transported to the downstream section and destroying infrastructure, as was the case in a less extreme event in May 2018. Therefore, such mitigation measures can also be used in other torrential catchment areas in the alpine environment.

How to cite: Sodnik, J., Mikoš, M., and Bezak, N.: Measures to mitigate torrential hazards in a typical alpine catchment area in Slovenia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21734, https://doi.org/10.5194/egusphere-egu24-21734, 2024.

Dunes react quickly to climatic changes, with the main drivers being the dominating wind regime (e.g. magnitude and direction), precipitation, and temperature. Further, human impact can alter dune movement by fixation of active dunes through greening projects, or reactivation of stationary ones through overgrazing by animals. The north-eastern Tibetan Plateau shows a high variability of climatic parameters like wind, temperature, and precipitation within a high elevation environment, situated between the mid-latitude westerlies and the East Asian Summer monsoon. The presented studies asses active barchan dunes in different climatic settings, from the arid southern margins of the Badain Jaran Desert, to the humid Zoige Basin.

Since climate stations on the Tibetan Plateau are rare and their measurements often cover only a short time span, climatic changes were studied from ERA-5 reanalysis data, dating back to the 1950s. These metrics were processed via cloud computing, using Google Earth Engine, and were then compared to dune migration rates, which were deduced from optical satellite imagery. Here, the CORONA KH-4B images from the late 1960s, the Landsat archives, and up-to-date high resolution data (GeoEye and WorldView) were used. The Normalized Difference Vegetation Index (NDVI) was implemented to observe changes in vegetation. As a newly tested metric, dune field density changes were calculated, in order to investigate dynamics of dense dune field setting.

Over 500 dunes were mapped and analyzed in total within four focus-areas for comparative purposes. The results highlight a wide range of different behavioral patterns of dunes within the environment of the north-eastern Tibetan Plateau. This showcases how dunes can be influenced by and linked to climatic changes.

How to cite: Dörwald, L., Lehmkuhl, F., Walk, J., Yang, X., Zhang, D., Baas, A., Delobel, L., Boemke, B., and Stauch, G.: Dunes on the north-eastern Tibetan Plateau as influenced by climate change: a remote sensing study of the past 5 decades , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1649, https://doi.org/10.5194/egusphere-egu24-1649, 2024.

The development of alluvial fans is sensitive to environmental change and, thus, alluvial fans provide essential archives for reconstructing Quaternary paleoenvironmental conditions, particular climate, hydrology, and tectonics. Although alluvial fans have been studied across the globe for over a century, there is no unifying scheme/framework or model to consider their complete variety and mode of formation. By reviewing the global spatial and temporal range of alluvial fan types and data from selected key dryland regions, we are able to develop a conceptual scheme/framework for their geomorphology and formation, and thus aid in their application for Quaternary climate and environmental change studies. This approach suggests that there are three main regimes for alluvial fan geomorphology and formation: Type I) microscale mountain alluvial fans, small in size and extent (radius < a few 100 m); Type II) mesoscale (radius

How to cite: Lehmkuhl, F. and Owen, L. A.: A conceptual model for alluvial fan formation and development , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1752, https://doi.org/10.5194/egusphere-egu24-1752, 2024.

Dryland soil salinization strongly affects soil properties, with severe consequences for regional ecology, agriculture and the aeolian dust dynamics. Given its climate-sensitivity it forms a serious environmental hazard, and to cope with this challenge during current global warming it needs to be better understood.

The Bajestan Playa, located in the heavily salinization-affected drylands of Iran, is home to several protected areas and serves as a crucial source of regional dust emissions. Consequently, soil salinization in this region affects both local ecosystems and societies but was not systematically studied yet.

Using an unprecedented comprehensive approach, we systematically monitored regional soil salinity from 1992 to 2021 through a combination of remote sensing, on-site field measurements, and laboratory analyses. We linked these data with regional and global climatic information to achieve three main objectives: (i) understanding the spatio-temporal dynamics of soil salinity, (ii) assessing the impact of regional and global climate changes on salinization processes, and (iii) exploring the potential applications of our approach for future soil salinity studies.

Our high-resolution annual data over three decades have provided significantly deeper insights into soil salinization dynamics. Furthermore, this pioneering, multidisciplinary research showcases substantial potential for future applications in other salinity-affected drylands forming a foundational knowledge base to address the consequences of ongoing global climate change.

How to cite: Khosravichenar, A., Aalijahan, M., Moazeni-Noghondar, S., R. Lupo, A., Karimi, A., Ulrich, M., Parvian, N., Sadeghi, A., and von Suchodoletz, H.: Monitoring and simulating dryland soil salinization and assessing the impact of climate change and global warming on soil salinity processes over the past three decades in the Bajestan playa (NE Iran), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2355, https://doi.org/10.5194/egusphere-egu24-2355, 2024.

The lower fourth member of the Paleogene Shahejie Formation (Es4^L) in Bonan sag, Bohai Bay Basin, East China was taken as an important target for oil and gas exploration in Shengli oilfield. Bonan sag is one of several sag in the Bohai Bay Basin, located in north-east China. Paleogene deposits are characterized by red rock layers, formed under a hot-warm and arid climate. Four depositional systems were developed in the Bonan sag. Among them, the fan delta developed in the central part of the study area, consisting of gray-white fine glutenite with poor sorting and rounding. The braided river delta is developed in the southern part with large lithofacies. The lithology shows some light gray conglomerate, pebbly sandstone, sandstone and small amount of mudstone. Floodplain facies is mainly developed in the inundated plain that in some weather conditions have the characteristics of shallow lake facies. However, a number of questions remain unanswered about the disparate presence of evaporites, the diverse colors of the mudstones and the varying levels of total organic carbon (TOC) in the area. These disparities can be seen in the many oscillations in TOC content, from the source of the sediments in the upper relief to the flood lacustrine plain. Consequently, given to this conditions, the depositional system which occurs in the area remains unclear from previous works. However, looking at the distribution of the sediments in an apparently short distance of less than 50km from the south to the North of sag, suggests that they are more likely to be terminal fan deposits. Terminal fans are an architectural system for draining and depositional process from high relief to flood plain, with gradual discharge of water through infiltration and evaporation. Although some researchers have conducted studies on terminal fans around the world, the concept remains unfamiliar and deserves to be more elucidated. This approach postulates to be useful to better understanding the sedimentary deposits in the Bonan sag and must be reviewed for similar hydrocarbon explorations elsewhere.

How to cite: Mioumnde, A. P., Zhang, L., and Yan, Y.: Paleoenvironment and Depositional Analysis of a Paleogene Formation: Terminal Fan Sedimentation Approach for Reservoir Quality Study in the Lower Shahejie Fourth Member, Bonan sag, China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2604, https://doi.org/10.5194/egusphere-egu24-2604, 2024.

 In view of the problem that the Cretaceous favorable sedimentary facies belt in Kedong structural belt in the southwest depression of the Tarim Basin is not clear, in order to reduce the uncertainty of the research on the spatial and temporal distribution of source sink sedimentary systems in low drilling density areas, the applicability of sedimentary forward modeling in the Tarim Basin is explored. Based on existing geochemical data, statistical analysis of trace elements and rare earth elements is conducted to explore the ancient sedimentary environment during the sedimentation process of the Cretaceous Kizilsu Group, which is a prerequisite for conducting sedimentary forward modeling. By comprehensively utilizing drilling, seismic and other data, combined with previous research results, DionisosFlow sedimentary forward simulation software is applied to clarify the development characteristics of sedimentary systems. The results show that based on different element abundances, ratios, and sedimentary markers, the study of ancient sedimentary environments shows that the ancient climate is mainly characterized by semi humid, semi dry, and dry hot climate conditions; During the sedimentation period of the Kizilsu Group, the overall water depth was relatively shallow, and the ancient redox environment was a shallow underwater oxidation environment. The favorable paleoenvironmental conditions and abundant material sources provide favorable conditions for the development of shallow water delta sedimentary systems. The Kizilsu Group mainly develops braided river delta sediments in the northern gentle slope zone, with front edge sediments as the main type. The southern steep slope zone develops alluvial fans and fan delta sedimentary systems, and the central part develops shoreline shallow lake facies sediments. The western Kunlun Mountains in the south are the main source of material supply, while the Maigaiti ancient uplift in the north is the secondary source of material supply. The ancient uplift during the sedimentation period of the Kizilsu Group has a blocking effect on the delta that flows into the lake, dividing the southern fan delta and lake sedimentary system from the northern braided river delta and lake sedimentary system.

How to cite: Zhang, Y. and Zhang, L.: Application of Sedimentary Forward Simulation in the Kezilesu Group of the Kedong Structural Belt, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2738, https://doi.org/10.5194/egusphere-egu24-2738, 2024.

Understanding and quantifying the natural variability and evolution of past climate systems require the use of datasets that are considerably long, continuous, and of broad spatial coverage. However, common terrestrial proxies, specifically in low- and mid-latitude could be puzzling due to the diversity of climate systems that records a mixed and regionally wide signal that fails to detect the short-term and transitional climate variability. In Holocene records, which are often used to study human-environment interactions, these resolutions are critical.

Here we explore the potency of deposits that are filling endorheic (internally drained) basins of not more than several km² in size to serve as paleoenvironmental archives. We focus on three sites spread along a steep, ~150 km long climatic gradient in Israel that are influenced by several atmospheric circulation patterns. Core-drilled sediments acquired from such basins have undergone sequential analyses to characterize their textural, geochemical, and luminescence properties. Optically stimulated luminescence (OSL) dating, applied to construct a chronological framework, is coupled with port/pulsed OSL (POSL) analyses, mainly to analyze sedimentation trends and target samples for OSL dating.

The geomorphic and sedimentological responses to environmental perturbations of the late Quaternary are reflected distinctly in each site. Changes in depositional environments that occur throughout all sites often point to similar regional climatic trends, and are partly synchronous with established climatic events.  The compiled interpretation from several sites along a given climatic transect is anticipated to form a robust regional paleoenvironmental framework that can serve a wide range of Quaternary studies.

How to cite: Raish, I., Roskin, J., Vainer, S., and Bookman, R.: Small endorheic basin sediments along a climatic gradient as paleoenvironmental archives, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3400, https://doi.org/10.5194/egusphere-egu24-3400, 2024.

The Ordos Plateau lies on the northwest margin of the East Asian monsoon region as well as the farming-pastoral ecotone in northern China, with a wide distribution of nebkhas. The formation and development of nebkhas in this region are closely related to natural envi ronmental conditions and human activities. However, the processes of nebkhas formation and development under natural and anthropogenic influence still remain unclear. In this study, four typical nebkhas in the Ordos Plateau were selected after detailed field investigations. Chronology and sedimentary features of the formation and development of nebkhas were studied based on optically stimulated luminescence (OSL) dating, lithology, grain size, etc. The results demonstrated that modern nebkhas had formed since at least ~0.59 ka in the southwest of the Ordos Plateau, followed by the middle region, at least ~0.34 ka, and later in the south and north regions, at least ~0.10 ka. There were thin layers of weakly-developed paleosols at ~0.32-0.25 ka, peaks in the silt and fine sand content and lower deposition rates, about 0.37-0.46 cm/a, indicating a relatively humid climate and weak aeolian activities. After ~0.10 ka, aeolian activities intensified and the nebkhas widely developed with a higher deposition rate, ~0.45-5.21 cm/a. Nebkhas in the study region developed primarily over paleo-channels or paleosol layers. Very fine sand and fine sand were dominant composition on grain size of nebkha sediments; saltation was a main means for the particle movements, indicating near-source accumulation for nebkha sediments. In recent decades, local farmers are used to adding nebkhas deposits to the soil of irrigation areas to improve the soil quality and alleviate soil salinization. Such agricultural activities, together with land reclamation, have accelerated the demise of the nebkhas in the Ordos Plateau.

How to cite: Du, Y., Lu, R., Ma, L., Chen, D., and Liu, Y.: The formation and development of nebkhas based on chronology and sedimentology in the Ordos Plateau, northern China, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5535, https://doi.org/10.5194/egusphere-egu24-5535, 2024.

Sand control is one of the most important components of environmental protection. In the middle reaches of the Yarlung Zangbo River, the phenomenon of desertification is becoming serious, which has a great impact on the local ecological environment protection and economic development. The accurate estimation of the volume of aeolian sediment is of great significance to the formulation of the treatment plan. However, most of the existing studies are based on remote sensing interpretation to estimate the area of aeolian sediment, and the research on the volume of aeolian sediment is relatively weak. To make up for this research gap and provide reliable basic information for sand control in the middle reaches of the Yarlung Zangbo River, we carried out research on estimation of aeolian sediment volume based on GPR and LiDAR. The experimental area of this study is located in Zhanang County in the middle reaches of the Yarlung Zangbo River, with an area of approximately 1.8 km². We set up six GPR survey lines in the experimental area and obtained the bottom interface and corresponding average elevation of aeolian sediment. Subsequently, high-precision surface elevation of the study area was obtained by LiDAR, and the average surface elevation was calculated. Then we obtained the average thickness of the aeolian sediment is 3.25 m by subtraction of the average surface elevation and the elevation of the aeolian sediment bottom interface. Finally, we determined that the volume of aeolian sediment in the experimental area was about 5,850,000 m³. Our study has realized the volume estimation of typical aeolian sediment area in the middle reaches of Yarlung Zangbo River, which has important guiding significance for sand control.

How to cite: Ling, J., Qian, R., Liu, X., Huang, Z., Wang, D., Hu, K., and Zhang, J.: Estimation of aeolian sediment volume in the middle reaches of the Yarlung Zangbo River based on GPR and LiDAR, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5537, https://doi.org/10.5194/egusphere-egu24-5537, 2024.

Climate change continues to impact diverse ecosystems. Drylands stand out as particularly vulnerable environments, as they are highly responsive to key indicators of change. The sensitivity and response time of these regions remain largely unknown, underscoring the need for a deeper understanding of their systems.

Arid regions are considered optimal for Earth Observation based research, primarily due to factors such as minimal anthropogenic disturbance, sparse vegetation cover, and low cloud coverage. These attributes make drylands advantageous for studying and monitoring the impact of climate change, providing valuable insights into these vulnerable ecosystems.

Southern Mongolia stands out as an especially well-suited study area to test novel approaches and to detect land surface changes over both space and time. The basin of Orog Nuur was selected in this study to observe long-term environmental changes, building on significant prior studies conducted around the drainage basin.

Our approach emphasizes the utilization of state-of-the-art earth observation technology to unveil the dynamics of desert ecosystems. This involves cloud-based processing, such as Google Earth Engine and the German High Performance Data Analytics (HPDA) platform “terrabyte”. Throughout the project, we will apply various multispectral and active SAR techniques spanning 50 years to monitor geomorphological processes, ecosystem changes and ongoing surface dynamics linked to climate change indicators. Some of important pillars of the long-term time series analysis can be listed as greening and precipitation events, lake level dynamics, dune movement rates, mapping of sedimentological, geomorphological provinces and aeolian coverage, in order to understand frequency-magnitude relationships.

The findings will be supported by a series of fieldworks covered by UAS campaigns and auxiliary ground-truth sensors, ensuring the accuracy of our estimations by in-situ measurements. Based on the derived surface characteristics, various ecosystems will be defined, and a high-level ecosystem integrity model will be developed. Ultimately, our model aims to represent the intactness, functioning and structure of the different ecosystems within arid regions. Additionally, due to our high temporal study concept, the model will serve as the base for quantifiable measurements of the responsiveness and adaptiveness of the ecosystems.

Having a model for ecosystem intactness not only help to preserve fragile ecosystems but also strengthens the resilience and adaptive capacity of communities. Furthermore, the transferability of our framework to other drylands may also lead to a comprehensive understanding of the arid characteristics.

Keywords: Earth Observation, arid regions, dryland, remote sensing, climate change, impact, geomorphological process, ecological modelling, land surface dynamics

How to cite: Arisoy, B., Ullmann, T., and Stauch, G.: Desert Sensing – Characterizing recent surface dynamics in arid regions through high-performance data analytics of multi-sensor Earth Observation archives and in situ records, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10337, https://doi.org/10.5194/egusphere-egu24-10337, 2024.

Mineral dust aerosol particles are tiny soil particles mobilized and entrained into the atmosphere by wind. Suspended in the atmosphere and transported away from source regions by prevailing wind systems, dust aerosol alters the Earth’s radiation budget, stimulates cloud and precipitation formation processes, and modulates the carbon cycle as it may enhance bio-productivity due to its mineralogical composition. In the light of the manifold dust feedbacks with relevance to the climate, knowledge on the atmospheric pathway of dust from source to sink is essential for accurate climate simulations. Thereby, the spatio-temporal variability of dust source activity, and consequent dust production and entrainment into the atmosphere is of particular interest as dust emission marks the beginning of the atmospheric dust cycle. Although crucial for the understanding of the climate system, detailed knowledge on the interannual variability of dust source characteristics (i.e., emissivity and their susceptibility to wind erosion) and activity (i.e., occurrence frequency of dust emission events and emission fluxes) is still somewhat limited. In particular the impact of changing environmental conditions on dust sources and their emission variability is not fully understood yet and requires further research. This is also of importance in order to assess the spatially and temporally changing contribution of dust sources to the local and regional atmospheric dust burden and related dust feedbacks.

This presentation will provide an overview of different dust source types, their key characteristics, and their response to environmental changes due to climate change with regard to emission flux and dust source activity. It will include examples from remote sensing approaches and dust modelling in order to examine the interannual variability in a changing climate.

How to cite: Schepanski, K.: Mineral dust in the climate system: Dust source types and their response to environmental changes in a changing climate, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11443, https://doi.org/10.5194/egusphere-egu24-11443, 2024.

Aeolian-Fluvial interactions range from aeolian- to fluvial-dominated processes, often resulting in unique morphologies and complex stratigraphies along dunefield margins. In the Northwestern Negev dunefield (Israel) desert, a key factor influencing transitions from aeolian- to fluvial-domination, is the basin size. While medium-sized (40-200 km²) and large (>200 km²) basins were breached before or during the early Holocene, small basins are still dammed by dunes. Often their surficial and buried palaeochannel is comprised of a sequence of remain of dune-dammed water bodies in the form of fossilized playas. Unlike medium and large basins, where incision exposes Aeolian-Fluvial deposits after the dune-dam breaching, small dune-dammed fluvial systems necessitate sampling techniques such as drilling into continuously aggrading Aeolian-Fluvial deposits to reconstruct the stratigraphy and interpret paleoclimate and palaeoenvironmental records. We demonstrate the potential of a SUERC Portable-OSL (port-OSL) for interpreting palaeo-records in small dune-dammed basins.

The Shivta-East basin (3.3 km²) was hand-augered along an ephemeral stream's propagation path into the dunefield, at three disconnected playa-like sediments of seasonal dune-dammed waterbodies. At each dune-dammed waterbody sediments, samples were taken at 15-25 cm intervals and analyzed using the port-OSL reader. Their estimated ages were interpolated according to a calculated regional linear regression based on the northwestern Negev dunefield luminescence age database. This regression, generated by training a data set of thirty-two aeolian sand samples, analyzed for both OSL dating and port-OSL Net counts, accounts for 72% of the age variability, with a standard error of 3.4 ka between the model and the data. Due to the absence of modern-day OSL dated samples, the regression line was reconstructed for the LGM until the early Holocene. The regression model enables dating of the Last Glacial Maximum, Heinrich-1, and Younger Dryas sand incursions, previously described as the main active periods of the aeolian system.

K-means cluster analysis based on the port-OSL signals, reveals three distinct clusters, which points to alternations of the sedimentary units, between sand and fluvial sourced fine-grained sediments. The three clusters are understood to reflect both the mineralogical composition and burial age of the deposits. The overlying cluster mainly consists of fine-grained sediments deposited in the dune-dammed waterbody, while the other two units are sandy deposits.

Interpolation of the sandy samples from all three playas along the palaeochannel in the linear regression demonstrates that during the Heinrich-1 and Younger Dryas events, an aeolian-dominated environment dune-dammed the fluvial system, enabling aeolian sand deposition. Later, coevally with the fluvial system's propagation into the second (middle) dune-dammed waterbody, aeolian domination persisted until the Early Holocene generating the third and upstream dune-dammed waterbody.

This study demonstrates the potential and limitations of the port-OSL reader combined with statistical methods for chrono-stratigraphic analysis of hand-augered samples collected from an altering depositional environment. The ability to rapidly estimated depositional ages and associated palaeoclimatic periods highlights the potential for further exploration of the port-OSL reader in different environmental settings.

How to cite: Greenbaum, N., Robins, L., and Joel, R.: Regional Depositional Age Assessment using Portable-OSL of Hand-Augered Aeolian-Fluvial Deposits along a chain of Small Dune-Dammed Basins in the Northwestern Negev Dunefield Margins, Israel , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12423, https://doi.org/10.5194/egusphere-egu24-12423, 2024.

The Great Central Desert of Iran, located at the center of the Iranian plateau, bears valuable but scattered geological and geomorphological archives. However, the scarcity of data on the paleoenvironment and paleolandscape of this area is attributed to challenging accessibility and harsh climatic conditions. The Khur area in the eastern edge of the Iranian Central desert was selected for this investigation due to its distinctive geomorphological features and improved accessibility.
This study aims to delineate Late Pleistocene-Holocene landscape evolution in central Iran by utilizing sedimentary and morphostratigraphical evidence of aeolian-fluvial sequences. In a first step, geomorphological features were mapped based on satellite imagery, digital elevation models, geological maps and field observations. Subsequently, localities for excavator sections were deduced from these findings, guaranteeing accessibility and further ensuring their incorporation of anticipated stratigraphic key features, including contact zones of distinct geomorphological environments. Stratigraphic description of the excavated profiles was recorded, and sedimentary logs were drawn.
The preliminary results reveal complex interactions of Aeolian, fluvial, and lacustrine morphodynamics during the Late Pleistocene and Holocene. Seven landform groups including aeolian dunes and interdune areas, sandy mud flat, alluvial fans and fluvial plains, dissected fan toe with backward erosional valleys were recognized. Within these, five interfingering sedimentary units were identified based on distinctive geometry and layering and their internal facies distribution: Fluvial flood deposits, well to poorly-sorted alluvial deposits, aeolian sand deposits, fluvially reworked marl (fine-grained mud), paleosol horizons.
In summary, repeatedly changed depositional environments and cyclical climatic changes, where dune development took place during phases of increasing aridity, whereas non-aeolian deposition and paleosol formation might have occurred during more humid conditions and more stable paleosurfaces.
Luminescence dating, sedimentological and geochemical analyses, will determine climatic cycles, sedimentary environments and landscape evolution history.

How to cite: Rashidi Koochi, Z., Büdel, C., Torabi, M., Baumhauer, R., and Fuchs, M.: Towards Late Pleistocen-Holocene stratigraphy and landscape evolution of Khur area, Central IranTowards Late Pleistocen-Holocene stratigraphy and landscape evolution of Khur area, Central Iran, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12653, https://doi.org/10.5194/egusphere-egu24-12653, 2024.

Sedimentary sequences with major aeolian dust contribution blanket the flat to hilly landscapes of eastern New South Wales. Originally identified by Butler in 1956 within the Riverine Plain and adjoining hills, these widespread clay-rich sediments were termed "Parna”. Parna – which has often been compared to loess – is thought to be fine-grained sediment generated through exogenic processes in arid environments and transported as stable aggregates by prevailing westerly winds during the Quaternary. The primary hypothesized source regions for Parna are arid and semi-arid river and lake systems situated in the western Murray-Darling Basin. Despite the prolonged critical discourse surrounding the concept and terminology of Parna, investigations addressing unresolved questions have been limited, with absolute dating of the aeolian sequences being restricted to only a few sites.

Given the complexity of the Parna sequences resulting from the interaction of aeolian, hillslope and pedological processes, we choose a multimethodological approach combining field observations, grain size analysis, geochronological and geochemical methods to investigate the processes and time frames of sedimentation and sediment provenance. Results of optically stimulated luminescence (OSL) dating for several Parna sites in the Wagga Wagga (Beattie 1972) and Yass region, show age estimates reaching back 150,000 years. Sedimentological parameters are used to distinguish between material derived from local hillslope and aeolian input. Geochemical characteristics will help to trace sources and pathways of the aeolian material. Advancing our understanding of the Parna concept, implying large-scale deposition but also deflation of aeolian material, is one component of reconstructing Quaternary landscape development and environmental conditions in south-eastern Australia.

Butler, B.E., 1956. Parna-an aeolian clay. Australian Journal of Science, 18(5), 145-151.

Beattie, J.A., 1972. Groundsurfaces of the Wagga Wagga Region, New South Wales. C.S.I.R.O Soil. Pub Australia. No. 28.

How to cite: Lauer, F., Marx, S., Dare-Edwards, A., and May, J.-H.: Reconstructing timeframes, processes and environmental implications of Late Quaternary aeolian Parna deposition in south-eastern Australia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13466, https://doi.org/10.5194/egusphere-egu24-13466, 2024.

The Tibetan Plateau (TP) is extremely sensitive to climate change. Widely loess deposits distributed in the Tibetan Plateau are important archives for studying the past environmental changes of the Tibetan Plateau. However, little information is understood due to the poorly age constrained of the TP loess. In this study, we use the single-aliquot regenerative dose optically stimulated luminescence (OSL) method, and the post-infrared infrared stimulated luminescence protocol (pIRIR) to date the well-preserved loess–paleosol sequences in the eastern TP and discuss the applicability and reliability of OSL dating of the TP loess for establishing a reliable numerical age framework. We found that quartz OSL signal of TP loess is dominated by fast component, and the equivalent dose can be measured by SAR method. The growth curve shapes and saturation dose shows that the quartz OSL signal in this region saturated at ~200～230 Gy. The prior-IR stimulation plateau test, dose recovery, recycling ratio and recuperation indicated that pIR₂₀₀IR₂₉₀ could be used for the equivalent dose estimation of potassium feldspar. Our results contribute to an improved understanding of the TP dust history and paleoenvironmental changes in the Last Glacial cycles.

How to cite: Yang, S., Liu, L., Li, Q., Li, P., and Luo, Y.: Optically stimulated luminescence dating of loess sequences in the Tibetan Plateau and their palaeoenvironmental implications, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15208, https://doi.org/10.5194/egusphere-egu24-15208, 2024.

The densely populated Thar Desert in the northwestern part of the Indian subcontinent contains a complex spatial pattern of now vegetated dune morphologies. There is a growing dataset of luminescence ages that demonstrates a dominance of Holocene dune dynamics in the preserved record (e.g., Srivastava et al, 2020; Parida et al., 2023; Nitundil et al., 2023). This region is undergoing rapid change in recent decades with widespread flattening of dunes for agricultural land, which is fed by the Indira Gandhi Canal that provides water for irrigation.

Our work has developed a training set of >40 samples with published luminescence ages to create a calibration approach for the signals measured using portable luminescence readers (POSL) (Nitundil et al., 2023). Other POSL signal characteristics, such as IRSL:BSL ratios are a good indicator that the Thar sands have a broadly common sedimentary provenance, as well as transport processes and post-depositional histories of mineral weathering. During this work, a rigorous exploration of sediment properties, including moisture content and presence of carbonate was undertaken, and from this, guiding principles for building a calibration curve were developed.

Vegetated linear dunes have been sampled in five regions along a ~75 km north-south transect in the western Thar. The POSL calibration has been applied to determine estimated ages for three dunes at the second most northerly site, to shallow depths (2 m) (Nitundil et al., 2023), and from multiple profiles within two dunes at each of three other sites along the transect (a further 19 shallow, 2 m profiles). Fieldwork in September 2023 focussed on obtaining close to full dune vertical profiles via auguring (~10 m depth) from three sites, as well as exploring dynamics across and along a dune using ~0.8 m hand dug pits. This presentation will highlight key findings from the calibration exercise, and present POSL-based ages estimates across the western Thar to explore what they reveal about Holocene dune accumulation in this region. 

References

Nitundil, S., et al. (2023) Applicability of using portable luminescence reader for rapid age-assessments of dune accumulation in the Thar desert, India. Quat. Geochron. 78, 101468.

Parida, S. et al. (2023) Luminescence Dating of Dunes in the Western Thar Desert:  New Data and Regional Synthesis. XXI INQUA Congress, 14-20th July 2023, Rome, Italy.

Srivastava, A., et al. (2020) Holocene palaeoenvironmental changes in the Thar Desert: An integrated assessment incorporating new insights from aeolian systems. Quat. Sci. Rev. 233, 106214.

How to cite: Nitundil, S., Stone, A., Srivastava, A., and Songara, K.: Holocene linear dune accumulation in the western Thar desert, India. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21074, https://doi.org/10.5194/egusphere-egu24-21074, 2024.

The hyper-arid Namib Sand Sea (NSS) represents a significant challenge to human occupation, yet, despite these challenges, Early Stone Age (ESA) and Middle Stone Age (MSA) tools are found across this landscape. Whilst surface scatters are hindered by a lack of clear stratigraphy, they provide a spatially integrated record of the structuring of landscape use through time and relationships to sources of raw material and water. Omitting such sites leads to bias in our interpretations of early hominin distribution. We are investigating how and why early hominins were moving into the northern NSS, starting with two interdune pan sites: Namib IV (Leader et al., 2023) and Narabeb. Here we set out the context of these archaeological sites, the stratigraphies observed and our emerging luminescence chronologies for the sedimentary sequences.

To establish the palaeoenvironmental context of the lithics (both ESA and MSA) and fossil fauna at Namib IV we dug a series of test pits to explore the sedimentological record. The Namib IV surface has a complex meso-topography with a spatially-patchy, resistant calcareous surface unit, and our test pits reveal a similarly complex sedimentary record across space. This includes the preserved remnant of an aeolian slip face, and elsewhere a number of horizontally bedded units beneath surface calcareous layers. 13 samples from Namib IV were selected for luminescence dating, using pIRIRSL feldspar methods, anticipating ages close to quartz saturation (e.g. Stone et al. (2010) in this region). Narabeb contains predominantly MSA lithics. North (~2 km) of the artifact collection area is a prominent ‘ledge’ of interbedded muds and sands, previously dated using quartz OSL (Stone et al., 2010). We dug two small geotrenches associated with surface calcareous exposures, taking samples for pIRIRSL dating along with two sampling points in the lower unconsolidated dune flank. We also date a sample from the Stone et al. (2010) sequence using pIRIRSL (K fieldspar) to revise the saturated quartz luminescence age estimate.

References

Leader, G.M., Bynoe, R., Marks, T., Stone, A., Efraim, K., Stratford, D., Marais, E. (2023) Revisiting the Acheulean at Namib IV in the Namib Desert, Namibia. Journal of Field Archaeology 48(5), 380-394.

Stone, A., Thomas, D.S.G., Viles, H.A. (2010) Late Quaternary palaeohydrological changes in the northern Namib Sand Sea: new chronologies using OSL dating of interdigitated aeolian and water-lain interdune deposits. Palaeogeography, Palaeoclimatology, Palaeoecology 288 (1-4), 35-53.

How to cite: Stone, A., Stratford, D., Marks, T., Bynoe, R., Efraim, K., Marais, E., Smedley, R., and Leader, G.: S.A.N.D.S. - Surface Archaeology on the Namib Desert Surface. , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21086, https://doi.org/10.5194/egusphere-egu24-21086, 2024.

Suspended sediment load in rivers has a crucial impact on the river water quality, soil erosion, irrigation activities, and dam or reservoir operations. Dam construction in a river reduces the runoff, which increases the deposition of suspended sediment on the river course and ultimately leads to a change in the river channel morphology. Thus, suspended sediment load prediction is significant for planning and sustainable management of the riverine ecosystem. Researchers have used various physical models, such as sediment rating curves (SRC), SWAT, HEC-RAS, HEC-HMS, etc., for predicting suspended sediment load. Recently, researchers have used machine learning models to predict suspended sediment load in different hydroclimatic regions worldwide. In this study, we used five different machine learning models, such as ElasticNetCV, Multi‑Layer Perceptron (MLP) Regressor, Extreme Gradient Boosting (XGB) Regressor, Light Gradient-Boosting Machine (LGBM) Regressor and Linear Regression (LR), for predicting suspended sediment load in a downstream station of Godavari River Basin (GRB). The GRB is the largest Indian peninsular river basin, covering more than 0.3 million square kilometers of area. We used the 'Lazy Predict' Python library to achieve better results for machine-learning modeling. The data was collected for the period of 1970–2018 and divided into two parts, viz. pre-1990 and post-1990, to consider the dam effects on the downstream regions of the GRB. Performance evaluation revealed that the Multi‑Layer Perceptron (MLP) Regressor performed very significantly, with an r-square value of 0.71 and 0.74, respectively, for pre-1990 and post-1990. The developed models offer a valuable resource for decision-makers, environmental scientists, and water resource managers seeking to proactively manage sediment-related issues in river systems, ultimately fostering sustainable water quality and ecosystem health.

How to cite: Kundu, S., Swarnkar, S., and Agarwal, A.: Application of Machine-Learning Based Models for Prediction of Suspended Sediment Load in the Indian Peninsular River Basin, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1117, https://doi.org/10.5194/egusphere-egu24-1117, 2024.

The Salton Sea in California’s Imperial and Riverside counties is a large endorheic lake with significant areas of exposed shoreline.  The exposed shoreline and surrounding desert are potential sources of wind-blown dust that can contribute to degraded air quality as the emissions create high concentrations of particulate matter ≤10 µm in aerodynamic diameter (i.e., PM10), which is a federally regulated pollutant in the USA.  The Salton Sea’s water surface height is lowering at an accelerating rate.  The decreasing volume of water leads to increased shoreline exposure with the potential for high wind speed events to cause dust emissions. This increases the potential for degradation of air quality with respect to PM10 mass concentrations within the basin potentially elevating the health risk to the surrounding population.  The State of California has implemented the Salton Sea Management Plan that has several phases of development to protect air quality and ecosystem values at the Salton Sea.  California Department of Water Resources (DWR) began a series of projects at the Salton Sea designed to limit dust emissions from shoreline areas deemed vulnerable to wind erosion and dust emissions based on evaluation of soil textural properties and in situ measurements of PM10 emissivity.  To protect sandy surfaces vulnerable to wind erosion, surface roughening based on the super-positioning of non-erodible roughness elements onto the exposed sediments of the shoreline has been implemented.  The non-erodible elements are bales of straw sourced from agricultural producers in the vicinity.  They are rectangular prisms of dimensions 0.41 m high, 1.12 m long, and 0.55 m wide. 

To evaluate the effectiveness of the roughness arrays, designed initially to offer 95% reduction in sand transport and dust emissions compared to the unprotected surface, computational fluid dynamics modeling was carried out to quantify the reduction in surface shear stress and dust emission potential due to the presence of the roughness.  In addition, in situ measurements of sand flux and PM10 concentrations were collected to corroborate the simulation results.  Air flow across the roughness array for three freestream wind speeds and three wind direction angles was simulated using CFD in OpenFOAM.  The mean shear stress reduction compared to the surface without roughness for the three freestream wind speeds and wind directions was 62% (±1%), 66% (±0.2%), and 79% (±1%), for 225°, 270°, and 315° wind directions, respectively.  The greatest probability for high wind speed events is expected from the wind direction range 225° to 315°. The mean reduction in total PM10 emission for these three conditions were: 73% (±4%), 85% (±2%), and 80% (±2%).  In situ measurements suggest control effectiveness is even greater as saltation has not been recorded within the roughness for the range of observed wind speed, and there is no indication that PM10 has been emitted from the protected surfaces.  This suggests that large size superposed roughness has effectively modified the dust emission potential of these susceptible surfaces and provides the protection needed to ensure that the exposed shoreline does not contribute to the regional PM10 burden.

How to cite: Gillies, J., Furtak-Cole, E., and Nikolich, G.: Large Scale Modification of the Salton Sea Shoreline to Reduce the Potential for Dust Emissions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1900, https://doi.org/10.5194/egusphere-egu24-1900, 2024.

Sand mining has accelerated in recent years primarily due to population increase and rapid urbanization. To meet demand, the rate of sand extraction often exceeds the rate of natural replenishment with serious environmental consequences. In this review paper, the Vietnamese Mekong Delta (VMD), a global hotspot for sand mining with a prolonged history of intensive riverbed extraction, is used as a representative case study to highlight the extent and compounded impacts of this activity. Sand mining budgets from literature present significant discrepancies, with estimates for the entire delta varying from around 8.5 to 42.2 Mm³/yr. These variances can be attributed to the challenges in the actual measurement of mining rates and the deployment of disparate methods across studies. Moreover, the widespread practice of illegal sand mining in the region further exacerbates the mismatch in budget calculations. Consequences of such mining activities manifest as deeply-incised riverbeds leading to riverbank and coastal erosion. Moreover, the massive sediment removal has resulted in river water level reductions, disrupted hydrological connectivity, and diminished floodplain inundation. The augmented backwater effect, a result of riverbed lowering, amplifies saltwater intrusion in dry seasons. While the physical and hydrological impacts have received attention, studies on the ecological and societal ramifications remain sparse. These impacts, further magnified by factors like upstream dams, irrigation infrastructures, excessive groundwater extraction, and sea-level rise (SLR), present a multifaceted challenge. This paper concludes by advocating for the adoption of remote sensing-based approaches for effective mapping of sand mining activities, and implementation of sustainable sand harvesting practices to balance developmental needs with environmental conservation.

How to cite: Park, E.: Sand mining in the Mekong Delta: Extent and compounded impacts, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2678, https://doi.org/10.5194/egusphere-egu24-2678, 2024.

The development of remote sensing technologies and image classification methods has facilitated research on changes in river channels and floodplains by automating mapping of land cover and geomorphic units. In often highly heterogeneous river environments, object-based approaches proved sensible, since they are based on objects produced by image segmentation rather than on individual pixels.

This study uses object-based image analysis to investigate land cover and river channel dynamics in the managed corridor of the Orljava River in the Pannonian basin (Croatia). In the last decade, the river has been affected by anthropogenic removal of riparian vegetation to increase channel capacity, which was followed by a big flood event. Five river corridor classes (water, bare soil, sparse vegetation, dense vegetation, and shadows) were classified based on RGB and near-infrared (NIR) aerial images in the period 2011-2021. A digital surface model generated from the images was used to separate bare river channel units (“river sediments”) from bare soil in the floodplain and to define high vegetation, while agricultural land was classified manually. The accuracy of the produced maps was between 85 and 93%, except for the year 2014 which lacked the NIR band. Based on classified river corridor units, changes in channel morphology were further analysed in GIS. The two main phases of river corridor changes were caused by the occurrence of a big flood in 2014. In 2011-2014, immediately after the flood, a significant increase in the area of water and river sediments was recorded, mostly at the expense of bare riverbanks and adjacent agricultural land. Large in-channel bars have formed due to sediment accumulation, as well as significant channel migration has been recorded. Contrarily, in 2014-2021 lower discharges allowed gradual channel narrowing and stabilisation, characterised by the spread and growth of vegetation in the river corridor.

Observed changes in channel morphology and vegetation succession are natural processes related to actively meandering rivers. However, it has been shown that extensive bank erosion during the flood and subsequent land cover dynamics were primarily triggered by anthropogenic removal of riparian vegetation exemplifying how inadequate and isolated river management decisions may increase bank erosion and lead to a loss of agricultural land in floodplain areas.

How to cite: Pavlek, K., Gašparović, M., and Poeppl, R. E.: Assessing river corridor changes after anthropogenic vegetation removal: an object-based mapping approach, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4096, https://doi.org/10.5194/egusphere-egu24-4096, 2024.

Downstream variation in bed material size was investigated over a stretch of the Yamuna River in the western Himalayan region in India. Data on grain size distribution along rivers are critical for understanding river systems and material transport. Flow regulation caused by dam construction can alter sediment transport mechanisms, generating morphological changes. Using an uncrewed aerial vehicle (UAV), we investigated precise grain size variation along the Yamuna River and its tributaries in the Siwalik region, from Lakhwar Dam to Hathni Kund Barrage. All photos were collected via UAV survey.

On these datasets, grain size variation was observed across dams. The upper Yamuna River's bed-load sediments are becoming finer-grained downstream. Since the dam barrier and low flow energy force large particles to remain above the dam, smaller particles are found downstream of the dam. During the survey, evidence of mining in several locations along the river suggests the influence of anthropogenic activity in the regions. Accordingly, this study sheds light on the potential consequences of dam construction on material transportation. We observed that dams work as a barrier for coarse grain particles, which may have an impact on the dam in the near future. Field evidence and preliminary processed data indicate that the size of the gravel bar along the river course has been modified by many human interventions (hydroelectric dams, barrages, mining).

How to cite: Patel, N. K., Schlunegger, F., Mair, D., Pati, P., and Prado, A. H. D.: Human impact on grain size variations of river gravel bars in the western Himalaya: Insights from a UAV survey, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4572, https://doi.org/10.5194/egusphere-egu24-4572, 2024.

Already at the end of the 19^th century, initial approaches were carried out to estimate the extent of anthropogenic mass transfer by humans on a global scale. In the course of the proposal of a new geological epoch, the Anthropocene, which is controversially discussed since the 2000s, anthropogenic geomorphological changes have received new attention. According to this concept, humans are moving more rocks and sediments worldwide than natural processes, with a supposed exponential increase in the mid 20^th century. Along with agriculture, mining activities are among the most important anthropogenic transformations of the earth's surface. Mining landscapes have become at many locations an integral part of landform development and a crucial element of the technosphere. In the framework of the Anthropogenetic Geomorphology, humans are considered as geomorphological agents, creating a variety of landforms, for which at the same time new classifications are needed.

In the present project an interdisciplinary environmental-historical approach is used to examine the question of when, how and to which extent humans have modified the relief landscape. As study area, the Harz Mountains in Northern Germany were selected, which represents one of the most important historical mining areas in Central Europe, especially for silver, lead and copper. They are a key region for the interconnectedness of human-nature interactions, which are reflected in a genetically complex landscape development. Humans have influenced the landscape of the Harz Mountains already since prehistorical times to varying extents. Distinct phases of landscape transformation will be distinguished in this study. However, one of the most significant landscape changes took place in the Early Modern Period, when the Harz became one of the largest industrial areas in Central Europe with some of the deepest shafts worldwide at that time and large-scale underground excavations. The main driver for the exploitation of ores was the interlinkage with the global metal trade and the arise of new economic and political systems during the Renaissance, whereas the mining operations mainly relied on the local availability of certain resources such as wood and water. The energetic base for the underground mining, reaching up to almost 1000 m below the earth surface, was the Upper Harz Water Management System, the largest historical energy supply system for mining, designated as UNESCO-World-Heritage site in the year 2010.

In a case study in the St. Andreasberg Mining District (West-Harz) as one of the centers of silver mining, the physical landscape changes are systematically examined in the context of litho-geomorphological, ecological and cultural-political aspects and in their spatio-temporal patterns. The focus of the study presented here lies on the type and dimension of subterranean relief changes in the lithosphere in connection with the correlating transformation of the reliefsphere and the hydrological system in the catchment area of the Oder-Sieber River system. The mining landscape is composed of anthropogenic landform assemblages, consisting of heterogeneous compositions of lithogenic, geomorphological, biogenic and aquatic elements, which are representative for the Upper Harz mining landscape.

How to cite: Iturrizaga, L. and Ließmann, W.: Anthropogenic landscape transformations and geomorphological landform assemblages in the context of historical mining in the Harz Mountains (Germany): Case study Sankt Andreasberg Mining District , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6818, https://doi.org/10.5194/egusphere-egu24-6818, 2024.

The urban landscape of the city of Rome exhibits a discernible urban-rural gradient, characterized by a diminishing anthropic impact from the central historic city to the outskirts and peri-urban zones, marked by increased open spaces and green areas. In the Aeterna Urbs, the Anthropocene epoch has seen significant urbanization and infrastructure development, frequently leading to profound alterations or complete obliteration of natural landscapes. The distinctive anthropogenic changes observed in Rome, characterized by their unique features, are not confined to the city; they are also evident in other contexts, underscoring commonalities and interconnections in how human activity shapes the landscape. In this regard, the city of Rome stands as an exemplar, offering a unique opportunity to delve into the human-induced changes and their impact on the natural geomorphological processes. However, despite their critical importance in understanding human-landscape interactions and the associated geomorphological risks, the role of human activity as a morphogenetic agent along the urban-rural gradient remains inadequately understood. This study addresses the tricky understanding of human-induced geomorphic changes, particularly on erosion, transport, and sedimentation processes, which pose threats to ecosystem functioning and impede efficient land use. The Malagrotta extraction area in Rome, Italy, characterized by a mining landscape of ridge removal, hillslope terracing and valley filling, offers a unique opportunity to assess the impact of topographical alterations on the geomorphic system. The investigation employs the widely accepted functional relationship between drainage area (A in m²) and slope (S in m/m) to delineate local process domains and facilitate the interpretation of process interactions. The slope-area function is applied to the same watershed across different periods using digital elevation models, offering insights into the evolving geomorphic dynamics influenced by human activities.

How to cite: Delchiaro, M., Vergari, F., Esposito, C., and Del Monte, M.: The influence of anthropogenic topographic changes on geomorphological processes in the city of Rome (Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9614, https://doi.org/10.5194/egusphere-egu24-9614, 2024.

The Bonneville Salt Flats, a landscape characterized by a perennial halite crust and seasonal flooding in western Utah, USA, provides a natural laboratory for advancing understanding of the processes that create and change dynamic saline environments. A decade of interdisciplinary research on the Bonneville Salt Flats has resulted in a new understanding of the salt's history, the functioning of the salt crust ecosystem, and the role that humans play in shaping this landscape. Sedimentological analyses of cores collected across the salt has changed our understanding of the history of the landscape, including evidence of extensive erosion after Pleistocene Lake Bonneville, the surprisingly young age of the oldest salt (~5.4 cal ka BP), and historical and ongoing crust halite dissolution. 16S rRNA gene and metagenomic analysis of the salt crust reveals a complex and robust microbial and archaeal ecosystem within the salt, hosting a wide range of metabolic pathways that actively cycle C, N, and S through the landscape. A long-term environmental observation station established at the center of the salt crust provides a robust new record of landscape processes, weather data, and eddy covariance flux measurements that have helped to constrain the energy and water budgets and highlight the sensitivity of ecosystem-scale surface conductance in the absence of vegetation to atmospheric drying. Arial and spaceborne remote sensing data show the impacts of over a century of human activities on landscape composition and texture, including groundwater extraction for potash mining, intensive surface modification, and land use associated with high-speed vehicle racing on the salt. Brine extraction and attempted mitigation have resulted in salinity and salt crust extent decreases over the last several decades, potentially limiting future landscape uses. The intricate interconnection of the human-natural system has enabled the exploration of variations in mental models influencing decision-making, attribution of blame, and the feasibility of adaptive management in dynamic landscapes serving diverse and conflicting needs. Integration of science with art has expanded the nature of the inquiry and led to new ways of thinking about human connections to a seemingly barren, but truly alive, place. All of these new insights into saline landscapes and the role that human land use and climate change play in altering processes are significant to understand as water delivered to closed basin saline lakes globally is in decline, potentially leading to an expansion of exposed salt-encrusted landscapes.

How to cite: Bowen, B.: A decade of interdisciplinary research on the dynamics of surface processes and landscape change at the Bonneville Salt Flats, Utah, USA, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9915, https://doi.org/10.5194/egusphere-egu24-9915, 2024.

Human pressures, in response to economic development and population growth, have been one of the main drivers of river systems changes especially since the second half of the last century. In the European context, anthropogenic impacts mainly concern with catchment land use changes, in-stream gravel mining, and in-channel works construction. The reconstruction of the past evolutionary trajectories and the temporal analysis of driving factors is considered fundamental to understand present river conditions, to support channel network management and to anticipate future changes.

The aim of this study is to investigate the anthropogenic factors that have impacted the geomorphological evolution of the Taro River (Northern Apennines, Italy) over the last 70 years.

Traditional methods based on multi-temporal orthophoto (1954, 1976, 1988, 1994 and 2020) analysis in GIS environment were used for studying historical channel changes along a channel segment 90 km long. Analyses of anthropogenic factors that may have influenced changes in the active channel included: (i) analysis of land use changes at the catchment scale, (ii) quantification of gravel mining activities, and (iii) analysis of in-channel work constructions.

Results showed that between 1954 and 1976 the Taro River channel width decreased by 39% on average, mainly in response to gravel mining activities, and subsequently to the increase of works into the channel. To the contrary, as a result of mining activities abandonment in the early 1980s, and of the occurrence of an extreme flood event in 1982, an increase of 18% in the active channel width was observed in 1988. The decreases in active channel width in the last 30 years (since the end of the 1980s) were correlated with the increase in forested areas in the catchment and with the increasing degree of stabilization of channel banks.

These studies are fundamental to identify management solutions in degraded rivers and to anticipate impacts in such rivers still featuring poorly impacted channel morphologies.

How to cite: Scorpio, V., Cervizzi, A., and Pittau, S.: The impact of anthropogenic activities on the geomorphological evolution of the Taro River over the last 70 years, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11466, https://doi.org/10.5194/egusphere-egu24-11466, 2024.

This study contributes to the topic of land surface degradation due to touristic activity by documenting examples of trail impacts related to initial trail development and high-intensity visitor usage. Our observations are based on a case study from the tropical Andes - Peru’s Rainbow Mountain (also named Vinicunca or Montaña de Siete Colores), which became a world-renowned tourist destination in recent years (after 2015/2016). The topic is important, as such high-mountain settings are very fragile, and degradation can occur rapidly – with long-term repercussions, as these landscapes tend not to recover quickly.

The main objectives of the study were to: (1) characterise and map different types of impacts related to direct visitor pressure, (2) document and evaluate activities aimed at limiting degradation while enhancing visitors’ experience, and (3) propose a conceptual model of trail functioning in the tropical high-mountain environment. Data were collected using ground-based surveys, unmanned aerial vehicle (UAV) and high-resolution satellite images.

Eight processes were responsible for transformation of the land surface: (1) trampling, (2) abrasion/shearing by visitors and service animals, (3) transformation of water and sediment circulation, (4) water erosion, (5) freeze-thaw cycles, (6) dry-wet cycles, (7) aeolian activities, and (8) mass movements. The five main trail impacts clearly visible in the landscape just after 1–2 seasons of intensive recreational use were: trail widening, trail incision, formation of braided trail networks, development of muddy sections, and development of informal (visitor-created) trails.

The hiking path was characterised by a width below 2 m and a low incision (<0.1 m incision on 80% of its length). The equestrian path was much wider (up to 17 m) and slightly more incised (<0.3 m incision on 69% of its length). The width of the multi-use path was up to 24 m. We suggest that the location of the trail in relation to the main geomorphological elements of the landscape (valley bottom vs slopes) and trail alignment to the terrain gradient have an essential impact on trail functioning and degradation. Specifically, trail sections routed through flat terrain and without lateral restrictions tend to widen and develop muddy sections, while sections routed parallel to steep slopes were prone to incision. Trails transverse to the terrain gradient were better drained but often developed into several parallel paths.

Undertaken trail management aimed to reduce negative visitor impacts and improve their safety and satisfaction. Successful measures included hardening the trail tread and marking the trail edges, which limited visitor dispersion and stabilised trail conditions. Partially successful actions involved installing artificial drainage (only partly preventing muddy section development) and providing separate paths for pedestrians and equestrians. After this change, the pedestrian trail was narrow and stable, but the equestrian path continued to degrade. Attempts to change visitor traffic patterns by relocating parking and abandoning a section of the trail were unsuccessful, as the new road and parking, and a new additional trail segment further degraded the landscape. Moreover, geomorphological processes continued to transform the abandoned trail section.

This study was funded by National Science Centre, Poland, project 2021/43/B/ST10/00950

How to cite: Tomczyk, A. and Ewertowski, M.: Land surface changes in response to touristic activity in the fragile, high-mountain environment: a case study of Vinicunca (Rainbow Mountain) in Andes, Peru, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12407, https://doi.org/10.5194/egusphere-egu24-12407, 2024.

Palaeochannels offer a glimpse into the history of a landscape. In the context of shifting perspectives from traditional hard engineering to soft nature-based measures, modern flood risk management could benefit from an understanding of the natural processes and features preserved within palaeochannels, which have otherwise been hidden by a legacy of engineering and land management on the river and floodplain. This study uses geophysical surveying techniques to bridge the gap between surface topography LiDAR data and sediment core data, in order to investigate the evolution of past rivers and tidal inlets in the Somerset Levels coastal plain and inland wetlands in southwest England. Case studies from a range of palaeochannels across the Somerset Levels are presented to identify the advantages and limitations of applying the methodology to a coastal plain and wetland dominated by Holocene alluvium and increasing human influence over the past several centuries. Four river systems represent both tidally dominated and inland freshwater conditions: a large tidal creek system within predominantly clay sediment; an inland river system traversing a peat wetland which was the former course of a major drainage network before intentional diversion; and two systems at the transition between tidal and freshwater influence.

Two-dimensional subsurface profiles derived from electrical resistivity tomography (ERT), shallow seismic refraction traverses, and ground penetrating radar (GPR) are used to laterally connect one-dimensional vertical sediment core data, and then integrated with the surface topography LiDAR data to construct channel and floodplain cross-sectional models. Past geomorphological processes – such as lateral migration, channel adjustment, and avulsion – are revealed in the preserved channel sediments, indicating responses to the contemporary climatic and anthropogenic conditions. Geophysical survey designs for identifying fluvial-geomorphological processes and features within palaeochannels are discussed, along with the need to adapt survey design for best resolution and depth in different, peat-dominated or clay-dominated, sedimentary settings. ERT is shown to consistently provide excellent depth penetration and estimations of channel extent. High resolution GPR data at the near-surface can be used in tandem with available core data to delineate the channel fill and bank geometry and calibrate depth estimations.

Flow conditions are reconstructed quantitatively using palaeohydrological drainage equations based on cross-sectional area values derived from the geophysical profiles. This avoids reliance on oversimplified cross-section estimates based upon surface parameters such as width and meander length, and one-dimensional depth estimates from core profiles. Existing hydraulic and drainage regime equations are tested against flow gauge data and channel measurements from active rivers to obtain optimal parameters for palaeohydrological calculations. These parameter estimates also benefit from on-the-ground channel parameter measurements in tandem with topographic remote-sensing. Hence, this study proposes a novel methodology that integrates geophysical surveying within palaeohydrological estimation techniques to improve models over long timescales of past fluvial environments that have been modified by humans.

How to cite: Anthony, J.: A geophysical study of palaeochannels on the Somerset Levels coastal plain and wetland to explore river landscape evolution., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12508, https://doi.org/10.5194/egusphere-egu24-12508, 2024.

Testing and improving the capacity of soil erosion and sediment delivery models to simulate the response of soil erosion to the intra-annual dynamics of climatic drivers and disturbances (e.g., vegetation clearcutting, tillage events, wildfires) is critical to understand intolerable soil loss and catchment sediment yields. Here, we approach the trade-off between the need for model simplicity and temporally dynamic predictions by testing the ability of a low-complexity, spatially distributed model (WaTEM/SEDEM), to decompose the 15-day dynamics of soil erosion and sediment yield. A standardised RUSLE parameterisation and model implementation routine was applied to four arable-dominated catchments in North-West Europe with open-access validation data. We firstly show that when applied to simulate the multitemporal dynamics of sediment delivery, a standard assumption of a temporally static transport capacity within the model structure mostly cannot adequately replicate the multitemporal variability of sediment delivery. Instead, optimising a 5-parameter splines curve to determine the temporal profile of the transport capacity coefficient (ktc) based on the monthly average sediment yield improved the model performance and revealed clear seasonality in the sediment transport efficacy. Despite simulating similar temporally aggregated sediment yields, the introduction of seasonal dynamics into the transport capacity further caused a net reduction in the magnitudes of the spatially distributed sediment fluxes, compared to a temporally lumped approach. Published catchment observations infer this seasonality in sediment transport efficiency to attribute abundant vegetative boundaries in summer and increased soil crusting and runoff promotion in winter. Models operating at temporally aggregated timescales should account for the possibility of decoupling in time and space between gross erosion and sediment delivery related to these alternations between transport- and detachment-limited sediment transport capacity states. Despite the complexities and uncertainties involved in the temporal downscaling of WaTEM/SEDEM, we show the utility of this approach to: 1) link optimised multitemporal parameters to key missing model information components which may reduce error in gross erosion predictions (e.g. more consideration of antecedent soil conditions), 2) form a basis for strategically adding physical process-representation, with a focus on maintaining low model complexity while improving predictive skill, and 3) better understand the interdependencies between spatial fluxes and multitemporal dynamics when undertaking model predictions at large spatial and temporal scales.

How to cite: Matthews, F., Panagos, P., Fendrich, A., and Verstraeten, G.: Testing a low-complexity model to decompose the multitemporal dynamics of soil erosion and sediment delivery in agricultural catchments, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13659, https://doi.org/10.5194/egusphere-egu24-13659, 2024.

Tailings are a by-product of the processing of minerals. Tailings can be highly erodible and transportable via fluvial processes and are commonly stored in ‘tailings dams’ which are a feature of many mine sites. These dams and their impounded material will become permanent geomorphic features in the post-mining landscape. The question examined here is - can tailings dams ever be walk-away structures? Tailings dams can fail by both catastrophic and gradual failure. Catastrophic failure occurs when there is a large scale rapid structural failure of the dam wall. Gradual failure occurs over time by slow infilling of the dam and the erosion of the dam wall. This can lead to overtopping of the dam wall and gully incision and failure of the wall and release of sediment to the environment. To understand failure modes and risk profile, computer based Landscape Evolution Models (LEMs) can be used. LEMs have become common tools to quantify risk for mine waste rock dumps and waste repositories.  LEMs provide detailed information on erosion rates, type of erosion and where erosion is likely to occur. They inform long-term behaviour which allows designs to be tested and improved. Here they are used to assess tailings dams where the strengths and weaknesses of different tailings dams designs are examined across a range of climates and material settings. The results show that if well-designed and assuming a well understood climate, a dam can be sufficiently robust to last centuries. However, failure can occur under different climate settings. Modelling also demonstrates that upon failure water quality will be affected for many centuries post-breach if no remedial work is conducted. Longer term, the tailings can be contained if there is maintenance and or an increase in the dam wall height over time or a more robust dam wall constructed to manage extreme events.

How to cite: Hancock, G. and Coulthard, T.: Assessing tailings dam long-term failure risk using computer based Landform Evolution Models , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14575, https://doi.org/10.5194/egusphere-egu24-14575, 2024.

Wind-disturbed mountain forests are often subject to artificial deadwood extraction and tree planting to accelerate the recovery of timber resources. However, little is known about to what degree and extent those post-storm silvicultural treatments modify the surface processes of wind-affected hillslopes. This study aims to understand how post-storm silvicultural treatments affect soil erosion from wind-disturbed mountain forests by coupling monitoring and modeling approaches. We continuously collected and measured soil losses from four 4.5-m-wide and 6.0-m-long bounded field plots located on wind-disturbed hillslopes with a slope angle of 45 % in a subalpine headwater of the Italian Alps during the vegetation periods from 2021 to 2023. The dominant ground cover of four plots resulting from altered post-storm interventions is characterized by residual deadwood, native herbs, 20-year-old plantation, and 5-year-old plantation, respectively. During 75 analyzed storm events, average soil loss from the native herbs-covered plot (2.4 t ha^-1; SD: ±3.5 t ha^-1) was the smallest, followed by plots covered with residual deadwood (mean±SD: 3.1±2.9 t ha^-1), 20-year-old plantation (mean±SD: 3.5±5.2 t ha^-1), and the 5-year-old plantation (mean±SD: 4.5±4.2 t ha^-1). Moreover, linear regression models (p-value < 0.001) indicated that two plantation plots potentially yield 2-fold sediment of naturally regenerating deadwood and herbs-covered plots as storm rainfall depth increases. Our three-year field observations highlight the persistent impact of post-storm forest management activities in accelerating soil erosion potentially even 20 years after their implementation. In the next step, the Water Erosion Prediction Project (WEPP) model will be used to further investigate the effect of human treatments on hydrology and sediment transport in storm-affected mountain areas.

How to cite: Koyanagi, K., Nordio, G., Andreoli, A., Tomelleri, E., Pöppl, R., and Comiti, F.: Legacy effects of post-storm silvicultural treatments on plot-scale soil erosion in a subalpine headwater catchment of the Italian Alps, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15250, https://doi.org/10.5194/egusphere-egu24-15250, 2024.

As the number and quality of satellite data detecting the Earth increases, a significant number of research fields are using these images, providing increasingly interesting results that were previously unimaginable. In this study, we extract the coastline from satellite images captured over a long period of time and analyze how the location of the coastline has changed in time and space.

Recently, many studies have attempted similar analyzes. However, the resolution of the image is low, so the results tend to be unreliable, as they often produce trend results of less than cm per year. Therefore, in this study, we first analyzed how reliable the trend results are depending on the amount of data, even if the resolution is low.

We also present a method to obtain the location of the coastline from reference points fixed behind the coast by linearly fitting nearby coastline points to reduce the error of coastline points extracted from satellite images. This method obtains the coastline position as the distance to the intersection of the base line and the fitting line and obtains the coastline gradient as the angle of the fitting line.

This method was applied to Wonpyeong-Chogok Beach located in the East Sea of the Korean Peninsula to analyze how the coastline has evolved over the past five years from 2019 to 2023, when coastal structures were built. On this beach, which has a total length of 2.9 km, three submerged detached breakwaters, two emerged detached breakwaters, and three groynes were built to reduce beach erosion. Reference points are located about 100 m behind the circular line that best fits the coastline, and the direction of base line is fixed to face the center of the fitting circle. Behind the emerged detached breakwater, the rate of change is up to 6.2m per year, and even in areas where structures have not yet been installed, there is a slight forward trend (0.4m/yr) due to the influence of beach nourishment. The standard deviation of the coastline position data for each base line ranges from 4.0m to 10.6m. Recently, Lim et al. (2022) presented the relationship between the standard deviation of the coastline data and sand grain size, and compared to the sand grain size results collected in the field, the grain size value was shown to be larger. The reason is that if the annual mean coastline is not maintained and continues to advance, the standard deviation increases. Considering this effect, the results are compared with observed sand gain size data. Therefore, it will be interesting to see how feasible it is to estimate the sand grain size from the analysis of long-term shoreline data obtained from satellite data, as in the results of this study.

Reference

Lim, C., Kim, T.-K., Kim, J.-B., and Lee, J.-L. (2022). A study on the influence of sand median grain size on the short-term recovery process of shorelines. Front. Mar. Sci. 9. doi: 10.3389/fmars.2022.906209

How to cite: Kim, E. H. and Lee, J. L.: Shoreline Change Analysis After Construction of Coastal Structures in Wonpyeong-Chogok Beach by Satellite Image Process, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16648, https://doi.org/10.5194/egusphere-egu24-16648, 2024.

Oases are man-made environment in response to hydro-climatic constraints of dryland. They form landscapes of natural origin that have been modified and exploited by the agro-pastoral practices of human societies. The oasis of AlUla, in Northwestern Saudi Arabia, is settled at least since the beginning of the Bronze Age. This oasis is located at the foot of the Harrat al-Uwayrid formation which separates the sandy deserts of northern Arabia from the Red Sea. AlUla has a long history of occupation, notably through the development of major archaeological sites such as the Late Bronze Age site of Dadan, the Nabataean site of Hegra, and the old towns of AlUla and Al Mabyat from the Islamic period. Recent research has also revealed the development of agro-pastoral activities since the Neolithic and hydroagricultural development from the Late Bronze Age onwards.

The aim of this research is to reconstruct the landscape of the AlUla oasis and thus to find out in what environmental framework these agro-pastoral societies developed. It also aims to study the role of climatic changes in the natural dynamics that have formed the geomorphology of the oasis (aeolian, fluvial, slopes processes and formations) and to determine the impact of human development. These objectives are to provide answers about the understanding of the current organization of geomorphological objects and their evolution/transformation through the Holocene and thus the interactions between societies and their environment that have produced them. This work has also enabled us to produce quantitative data on the volumes of earth moved/excavated since the rampant urbanization of the oasis, and to identify the practices (quarrying vs. levelling) and geomorphological environment most affected by these earthworks.

To achieve these objectives, we have produced a diachronic geomorphological map covering the AlUla oasis and its margins, with the aim of tracing the natural history of the oasis from its current state back to the Neolithic/Early Holocene. This realization of this map is based on a combination of geomatics methods, using a DEM produced by LiDAR data (2018, 40 cm accuracy), orthophotographs (2018, 10 cm accuracy), remote sensing with satellite images (1965-2024 Google, Bing, Corona), geological data (1:500,000) and fieldwork in order to inventory landforms and determined their organization and their chronology (C14, OSL).

Our results show a long-term trend towards aridification since the second half of the Holocene and an increase in human pressure since the Bronze Age. This last observation result from the initiation and expansion of agricultural practices supported by earthworks which have led to the development of levees along wadis, agricultural terraces and anthroposols. These anthropogenic forms associated with numerous excavations have greatly modified the initial topography and therefore the geomorphology of the oasis, from the Bronze age but with an astonishing and constant acceleration over the last thirty years. This demonstrates that the natural dynamics which have prevailed during the Holocene are progressively replaced by the impact of human societies, acting as an agent of erosion in the oasis environment in NW Arabia during the Anthropocene.

How to cite: Fernandes, A., Lespez, L., Davtian, G., Djerbi, H., Rouvier, C., Costa, S., Andrieux, E., and Purdue, L.: Natural dynamic vs anthropogenic transformations of the AlUla oasis, NW Arabia, during the Holocene: a combination  of geoarchaeology and geomatic approaches, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18146, https://doi.org/10.5194/egusphere-egu24-18146, 2024.

The anthropogenic pressure on European rivers has greatly intensified since the Industrial Revolution through channelisation, rectification, and building of dams and weirs. Against this background, focusing on the Vosges Mountains (NE France) is particularly relevant since it is the most densely populated mountain range in France. The Vosgian hydrographic network was accordingly impacted by widespread human modifications. No less than ~5000 hydraulic structures (HS) mostly involving weirs were built across the main streams draining the massif. Contrary to large rivers (e.g. the Rhine), the edification periods of these HS in smaller catchments remains largely unknown yet, thereby impeding a precise chronological reconstruction of the main phases of human pressure and environmental trajectories.

In this study, we aim to gain insight into the spatio-temporal anthropisation of three main streams draining the southern part of the Vosges, i.e. the Fecht, Vologne and Moselotte, and to evaluate their historical morphodynamic adjustments from the end of the 18^th century onwards. We took advantage of the abundant paper archives, i.e. written reports, plans…, from the “Ponts et Chaussées” administration, which collected at the local scale every official request to build HS along and across streams from the 18^th to the 20^th century. Firstly, we characterised and mapped every weir and levee along the three studied streams to produce an updated database of the present distribution of HS. Secondly, we analysed the archives to date the construction (and in some cases deconstruction) of the HS. Finally, we reconstructed the diachronic evolution of the channel pattern, from an ancient topographical map (1866) and two orthophotos (1951, 2018). Our results allow a first quantification of human impacts: the year of construction (terminus ante-quem) could be assigned to 7%, 38% and 59% of the weirs currently present in the Fecht, Vologne and Moselotte, respectively. Most of them were probably built in the middle of the 19^th century. Importantly, we also evidence a spatio-temporal correlation between the construction of HS and the simplification of the channel pattern. Although the use of historical documents has several limitations (e.g. loss, destruction, unavailability), we demonstrate that they are valuable archives that usefully complement field observations and investigations.

How to cite: Jautzy, T., Jacob-Rousseau, N., Berthier--Laumond, S., Claudepierre, M., Rixhon, G., and Schmitt, L.: Quantifying human impact during industrialisation on the evolutionary trajectory of Vosgian streams (NE France): the value of documentary archives , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18350, https://doi.org/10.5194/egusphere-egu24-18350, 2024.

Many human interventions in river systems, e.g., river channelization, hydropower dams, or restoration measures, affect geomorphological and sedimentological settings. Anthropogenic impact can lead to alterations in stream dynamics and sedimentary imbalances, as recorded in the sediments of large riverplains.

In the project “From Romans to the Anthropocene, from Carnuntum to Vienna: An Urban Anthropocene Field Lab” (WWTF ESR20-027) we explore long-term urban and geomorphological transformations within the Danube floodplain between Vienna (Austria) and Bratislava (Slovakia). Combining historical and sedimentological methods, our research focuses on the development of a very old settlement area within the transition zone between eastern and Central Europe.

Extensive river engineering, starting in the 19^th century, was a precondition for Vienna’s development as a residence and metropolis. This includes extensive river training and the construction of flood control structures. After a long period of river engineering and the construction of many hydro-power dams along the upper Danube, around 2000 the local removal of river bank fortifications started and also the restoration of fluvial dynamics primarily within our study area downstream of Vienna, in the free-flowing river section of the Donau-Auen National Park.

Fine overbank deposits record river dynamics through climatic and anthropogenic drivers. Reading the sequence of alluvial deposits allows us to understand the human impact on floodplain morphology. The great advantage of analyzing sedimentary archives is the temporal depth they offer: we can evaluate the conditions prior to river training (~200 years ago), the effects of engineering measures (e.g. river channelization, construction of hydropower stations), and recent restoration measures as well.

The characterization of sediment archives, including sediment dating (radioactive isotopes, OSL, dendrochronology), provides information on major flooding events, changes in the flow regime, and the dynamics of sedimentation. For investigations into sedimentary processes and river morphology downstream of Vienna, it is also necessary to have a look not only at the present state of a trained river but also at the former, near-natural situation of the riverscape. Therefore, comparisons of changing river morphologies before, during, and after the erection of dams and weirs are a requirement.

How to cite: Weissl, M., Hatzenbühler, D., Baumgartner, C., and Wagreich, M.: Reading the sedimentary archives in the Danube floodplain downstream of Vienna (Austria), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19923, https://doi.org/10.5194/egusphere-egu24-19923, 2024.

The interdisciplinary project, titled 'Living together or apart? Unravelling the development, internal organization, and social structure of a complex Bronze Age tell settlement at Toboliu, western Romania,' seeks to analyse Bronze Age settlement activity in Toboliu, located in the easternmost Carpathian Basin. Key aspects of the study include associated land-use and landscape evolution, making the reconstruction of the tell's surroundings a focal point. The study area is dominated by loess and significantly influenced by both modern and prehistoric agricultural practices. Thus, it is a major challenge to differentiate between landscape features caused by natural soil-landscape formation processes and human activity especially for the investigated period. Within this context we focussed our research on closed depressions surrounding the tell and investigated two hypotheses regarding their formation: i) closed depressions result from human activities (such as daub extraction pits) and ii) formed through natural soil-geomorphological processes (like loess dolines or periglacial relicts). Based on core drillings, we made use of Optically Stimulated Luminescence (OSL), radiocarbon-supported, and palynological chronostratigraphical analyses. In addition, we took advantage of spatial analysis involving a high-resolution LIDAR elevation model, multispectral WorldView-3 imagery, and magnetographic data to thoroughly testing both hypotheses. Our results suggest that the examined closed depressions exhibit characteristics reminiscent of specific periglacial relict forms, more commonly known from northern European landscapes. Details will be discussed within the presentation.

How to cite: Zickel, M., Nett, J. J., Röpke, A., and Reimann, T.: Unraveling Geomorphological Processes and Anthropogenic Activity at the Eastern Border of the Carpathian Basin: Insights from the Bronze Age Tell site Toboliu, Romania, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1638, https://doi.org/10.5194/egusphere-egu24-1638, 2024.

In antiquity, the development of techniques to collect and store water was fundamental to sustain life in arid regions. One way to overcome the problem of water supply in the desert was to construct water reservoirs and cisterns which collect surface runoff during rare rain events. Indeed, open reservoirs and rock-cut cisterns are widely spread over the arid zone of the Negev Highlands / Israel. They were an important component of human activity in the area. Today, they can serve as sedimentary archives for archaeological and paleoenvironmental reconstruction. Here we provide the final assessment of a large-scale optically stimulated luminescence (OSL) dating project of water installations in the arid Negev Highlands. By sampling spoil piles, feeding channels, and accumulation of sediments within reservoirs and cisterns, the construction, the phases of maintenance and abandonment were dated. The significance of these results for reconstructing the history of human activity in the region is discussed.

How to cite: Fuchs, M., Junge, A., and Lomax, J.: Chronology of ancient water installations and the history of human activity in the Negev Highlands, Israel , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2124, https://doi.org/10.5194/egusphere-egu24-2124, 2024.

Up to several meters thick fine-grained Holocene overbank deposits are ubiquitously found in most Western and Central European lowland floodplains. However, the interplay of different possible causes for their formation are not well understood yet. Most authors suggest human-induced deforestation as the main precondition for sediment mobilisation and transport from the slopes to the floodplain, generally regarding overbank sediments as human-derived ‘legacy sediments’. In contrast, others suggest a stronger influence of climatic factors. This current research gap is caused by often missing well-resolved fluvial chronostratigraphies and spatio-temporal information about former human activity within the studied catchments. To fill this gap we exemplarily studied Holocene overbank sedimentation and possible human or natural drivers in the meso-scale Weiße Elster catchment in Central Germany by using a comprehensive geoarchaeological approach: On the one hand, we applied numerical dating as well as sedimentological and micromorphological analyses to Holocene overbank sediments along three floodplain transects. On the other hand, we built up an unprecedented systematic spatio-temporal database of former human activity within the catchment from the Neolithic until the Early Modern Ages. Together with published paleoclimatic data, this database allowed an unprecedented, systematic comparison of Holocene overbank sedimentation phases with possible human and natural external controls. Our data show that some overbank sedimentation phases were directly linked with human activities in the affected site sub-catchments, whereas others were not. Instead, all phases were clearly linked with natural factors, i.e. hydroclimatic fluctuations. This difference with most former studies could possibly be explained by previously often limited numerical dating of the fluvial sediments and by largely missing spatio-temporally well-resolved regional settlement records, hindering a precise temporal link of fluvial sedimentation with former human settlement. Furthermore, this difference could possibly also be explained by a relatively high natural sensitivity of the landscape dynamics in the Central German lowlands, showing a subcontinental climate, towards external controls.

How to cite: von Suchodoletz, H., Khosravichenar, A., Fütterer, P., Zielhofer, C., Schneider, B., Sprafke, T., Tinapp, C., Fülling, A., Werther, L., Stäuble, H., Hein, M., Veit, U., Ettel, P., Werban, U., and Miera, J.: Holocene overbank sedimentation in Central Europe between natural and human drivers – the Weiße Elster River (Central Germany), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4080, https://doi.org/10.5194/egusphere-egu24-4080, 2024.

The Austronesian population, which consists of approximately 0.4 billion people, is widely spread across the Pacific and Indian Ocean islands. Extensive research over several decades has led to an academic consensus that the Austronesian population originated from Taiwan and the southeastern coast of mainland China. However, the exact manner in which the Austronesian ancestors arrived in Taiwan and subsequently dispersed to other oceanic regions remains a mystery. By analyzing the last deglacial sea-level rise, neotectonic activities, and resulting ancient environmental changes, as well as comparing the characteristics of middle Neolithic remains (dating back approximately 7.4-4ka) between the Taiwan Strait, we have proposed the existence of a “proto-Austronesian culture” in the early Holocene (around 11.7ka~7.4ka). This culture was centered around the nearshore area of the Taiwan Strait and Taiwan Shoal region. As sea levels gradually rose, the Austronesian ancestors’ habitat became increasingly submerged, compelling them to retreat to the inshore highlands on both sides of the Taiwan Strait. The Austronesian relics discovered on both sides of the Taiwan Strait, such as Dabenken, Keqiutou, and Fuguodun, among others, are actually branches of the Austronesian ancestors, inheriting their marine ecological characteristics. The scarcity of Neolithic artifacts older than 7.4ka on both sides of the Taiwan Strait can be attributed to a “survivor bias” phenomenon. It is plausible that numerous early Holocene relics of the “proto-Austronesian culture” remain submerged in the nearshore area of the Taiwan Strait and Taiwan Shoal, eagerly awaiting discovery through submarine archaeological exploration.

How to cite: Zhang, K. and Zhang, S.: Unraveling the Origins and Dispersal of Austronesian Culture by the last deglacial sea-level rises and paleoenvironmental changes: Insights from the Taiwan Strait, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4518, https://doi.org/10.5194/egusphere-egu24-4518, 2024.

Poland's landscape is a testament to its deep-rooted agricultural history, characterized by ancient field systems echoing the spatial layouts in Celtic fields throughout Europe. These intricate and expansive layouts pose a significant challenge for archaeologists and researchers dedicated to uncovering the secrets of the past. The focus of this study is to meticulously explore and analyze these extensive field systems, which often cover large areas and require a detailed and systematic approach. To navigate this complex task, researchers employed cutting-edge deep learning neural networks (DLNN), particularly the U-Net model. This approach involved semantic segmentation of data derived from Airborne Laser Scanning (ALS) to automate the identification of these significant archaeological sites. The team successfully identified hundreds of ancient sites across Poland by harnessing the power of ALS data combined with thorough desk-based analysis.

The research concentrated on specific sites in southern Poland, namely in the areas around Trzebinia and Jaworzno. Various geophysical methods were utilised here, including Magnetometry and the Slingram Electromagnetic Induction Method. These techniques aimed to confirm the existence of preliminary archaeological features in the region. The researchers conducted Magnetic Gradiometry and Electromagnetic Measurements across different terrains, including cultivated fields and forests. They specifically targeted relict embankments that once delineated old fields. The findings from these investigations were striking. The geophysical profiles of the two studied areas revealed significant differences. In the first area in a current crop field, researchers observed point-like, strong anomalies in both vertical magnetic gradient and electrical conductivity. In contrast, the wooded study area exhibited weaker but continuous anomalies, suggesting the presence of buried burnt clay formations. A key aspect of this research was integrating Ground Conductivity assessments with vertical magnetic gradient evaluations. This approach was crucial in correlating data from both methods. At the first site, variations in conductivity at different depths hinted at geological transitions or man-made structures beneath the surface. Meanwhile, at the second site, resistivity patterns suggested an anthropogenic alteration of water conditions, possibly resembling an artificial fault.

Integrating a machine learning system into this research process marked a significant advancement. It facilitated the automated segmentation of ALS data, greatly enhancing the efficiency of detecting and mapping cultural resources over large areas. Combined with traditional geophysical methodologies, this innovative approach provided a non-invasive means of identifying potential archaeological objects. This was crucial for the effective management and preservation of heritage sites. In summary, this comprehensive interdisciplinary study represents a fusion of advanced technological solutions with traditional geophysical methods. It offers valuable new insights into detecting and interpreting archaeological features, potentially revolutionizing the field of archaeological exploration and heritage conservation. The research highlights the importance of integrating diverse methodologies to uncover the intricacies of our past, ultimately contributing to a deeper understanding of human history and its impact on the landscape.

How to cite: Oryński, S., Marciniak, A., Berezowski, P., Banasiak, P., and Cader, J.: Application of shallow geophysical methods and machine learning for detecting remains of early medieval settlements in south-eastern Poland., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8532, https://doi.org/10.5194/egusphere-egu24-8532, 2024.

The surroundings of the Strait of Gibraltar in southern Iberia are well known as a crossroads for population movements, cultural exchange and trade from Late Prehistory to Modern Times. However, questions remain about how this historical development has impacted the environment. The settlement of La Silla del Papa, an important hillfort located in the Sierra de la Plata in southern Andalusia (Cádiz), and its territory represent an ideal location for long-term studies of human-environment interactions. It was occupied throughout the entire Iron Age, replaced by the coastal town of Baelo Claudia during Roman times, and reoccupied in the early Middle Ages. Therefore, the geoarchaeological investigations in the surroundings of La Silla del Papa within the framework of the interdisciplinary project “Archeostraits” aimed at constraining the ecological conditions and human-environment interactions during the Mid- and Late Holocene and during the most important human occupation phases. Our investigations included sedimentological, geochemical, chronological (OSL, ¹⁴C-AMS, diagnostic pottery), microfaunal and palynological analyses of nine sediment profiles as well as nine vibracores from the catchment of the Río del Cachón, a small river originating in the Sierra de la Plata, just below La Silla del Papa. Our results document an early Mid-Holocene open marine embayment in what is now the lower floodplain, which rapidly transformed into a coastal lagoon and later into freshwater-dominated wetlands. After ~2100 BP, fluvial and alluvial deposition considerably increased, suggesting high anthropogenic impact on the local landscape during the Roman or post-Roman times. Palynological results reveal fluctuating agricultural and pastoral activities and suggest two distinct periods of landscape opening between 7000-6000 BP and during the Phoenician and Iron Age period.

How to cite: Brill, D., May, S. M., Norpoth, M., Pint, A., Shumilovskikh, L., Raith, K., Rixhon, G., Moret, P., Jiménez-Vialás, H., Grau-Mira, I., García-Jiménez, I., Marzoli, D., León-Martín, C., Reicherter, K., and Brückner, H.: Palaeoenvironmental changes and human-environment interactions in the surroundings of La Silla del Papa, SW Spain, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10076, https://doi.org/10.5194/egusphere-egu24-10076, 2024.

An impressive relic of the scale of human-environment interaction and land modification in prehispanic South America are agricultural terraces, covering slopes across the Andes and of which only a fraction is still in use nowadays. Despite the ubiquity of agricultural terraces in the Andes, there is a lack of systematic studies that combine the investigation of farming terraces, land use history, and settlement patterns, preventing a comprehensive understanding of prehispanic socio-economic-ecological systems and human-environmental interactions. Our project develops and applies an integrative and interdisciplinary methodological approach to the study of prehispanic Andean terrace agricultural systems and associated settlements, providing reliable data on the dynamics of land use-settlement systems through time and space. Our methodological approach consists of the application of a variety of archaeological and geoscientific methods, including archaeological and geomorphological surveys, archaeological excavations, drone surveys, mapping using satellite imagery and high-resolution digital elevation models, geographic information system applications, soil testing, phytolith and starch analysis, numerical dating, and calculations of food supply capacity and labour requirements.

We apply these to the prehispanic site of Cutamalla (3,300 m asl) in the southern Peruvian Andes, which serves as an ideal and pioneering case study. Previous research has focused primarily on the settlement of Cutamalla, particularly through large-scale archaeological excavations, but less attention has been paid to the extensive farming terraces surrounding the settlement and the close relationship between agricultural and settlement activities. By analyzing both the terrace and settlement levels, we take a new perspective and introduce the term agricultural terrace-settlement system for such complexes. Our results show that the residential occupation of Cutamalla and the use of the surrounding farming terraces coincided: the agricultural terrace-settlement system was intensively used for a relatively short period of about 200 years (~250–40 BCE) during the Formative Late Paracas and transitional Initial Nasca periods. There is no evidence of reoccupation of the site and subsequent reuse of the agricultural system. Our data also document the large extent of agricultural terraces around Cutamalla (221 ha) and that maize was likely a major crop grown there. Finally, we place these findings in their broader socio-economic and ecological context. Cutamalla was an important regional center and economic hub during a very dynamic period characterized by significant population growth and increased violence. Not only a more humid climate, but probably also forced collective labor were cornerstones of substantial agricultural production in Cutamalla and the region.

How to cite: Meister, J., Binder, C., Dietrich, L., Godde, P., Leceta, F., Lyons, M., Marsh, E., Reindel, M., and Mader, C.: Prehispanic agricultural terrace-settlement systems: an integrative approach to study land use and settlement dynamics in the southern Peruvian Andes, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12670, https://doi.org/10.5194/egusphere-egu24-12670, 2024.

As archeological sites are not isolated islands, they exert horizontal and vertical influence on their surrounding area. Therefore understanding the impact of these sites on their periphery becomes crucial.  Soil and sediments, as reliable historical archives, provide a unique opportunity to investigate these processes. Recent research has demonstrated that not all markers of human activity are visible, and a combination of physical and chemical methods, including pOSL and pXRF analysis, can provide insights into hidden past human signatures.

Core drills conducted at the footslope of Tel Burna In Israel's archaeological site revealed an anthropogenic unit buried within the valley. This unit also contains a layer indicative of heightened anthropogenic activity, which could either signify the remnants of an ancient field's surface or the site's abandonment, followed by rapid site erosion. Given that these drills spanned from the slope of the Tell to the valley below, we were able to track the sediment's properties from the top of the site down to the valley. It was shown that the anthropogenic influence reduced with distance from the site, resulting in increasingly intricate patterns, suggesting multiple sources of sedimentation—both natural and anthropogenic. Furthermore, the study revealed a cycle of deposits that were transported to the site from the adjacent valley through human material transport activities to be subsequently eroded back into the valley due to natural processes. In summary, the ancient archeological site during its occupation and abandonment is still a physical feature that has been contributing to the landscape cycling processes.

How to cite: Ackermann, O., Janovský, M., Nikolskaia, P., Fišer, J., Anker, Y., Anker, Y., Ben-Gedalya, T., Friedman, A., Hejcman, M., and Shai, I.: Deciphering Hidden Ancient Human Physical and Chemical Markers through pOSL and  pXRF Analysis: A Case Study at Tel Burna, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14063, https://doi.org/10.5194/egusphere-egu24-14063, 2024.

After the retreat of the Weichselian glaciers, Northern Europe was populated by highly mobile hunter-gatherer groups. Traces of these societies are difficult to find, hampering our understanding of their life. Some remote basins of the western Baltic Sea, however, only drowned in the Holocene, and it has recently been postulated, that they preserve architectures from the Stone Age, that did not survive on land. In 2021 we documented the Blinkerwall, a stonewall megastructure located in 21 m water depth in the Bay of Mecklenburg, Germany. Shipborne and autonomous underwater vehicle hydroacoustic data as well as optical images show that the wall is composed of about 1700 stones, predominantly less than 1 m in height, placed side by side over 971 m in a way that argues against a natural origin by glacial transport or ice push ridges. Combining this information with sedimentological samples, radiocarbon dates, and a geophysical reconstruction of the paleo-landscape, we suggest that the wall was likely used as a drive lane for hunting during the late Pleistocene or earliest Holocene. Ranging among the oldest hunting structures on Earth and the largest Stone Age structures in Europe, the Blinkerwall will become important for understanding subsistence strategies, mobility patterns, and inspire discussions concerning the territorial development in the Western Baltic Sea region.

How to cite: Geersen, J., Bradtmöller, M., Schneider von Deimling, J., Feldens, P., Auer, J., Held, P., Lohrberg, A., Supka, R., Hoffmann, J., Eriksen, B. V., Rabbel, W., Karlsen, H.-J., Krastel, S., Heuskin, D., Brandt, D., and Lübke, H.: A submerged Late Pleistocene hunting structure in the Western Baltic Sea, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15442, https://doi.org/10.5194/egusphere-egu24-15442, 2024.

Grotta Romanelli (Apulia, southern Italy) is a key-site in Mediterranean archaeology. In the long history of excavations since the early 20^th century, its sedimentary archive has revealed important information about human frequentation, vertebrate faunas, and environmental changes, inside a time frame which includes the Middle Pleistocene (ca. 350 ka BP) and the Early Holocene (ca 11 ka BP). The peculiarity of the sedimentary succession, which consists of fine- to very fine-grained sediments with weakly-developed or massive sedimentary structures, determined a thorough micromorphological investigation. Indeed, these sedimentary structures are often associated with human-settled cave environments. Thus, the micromorphological analysis is of utmost importance for determining the sedimentary and geomorphological context of an archaeological site. In this respect, we present for the first time the results at a more detailed scale of the depositional environments of Grotta Romanelli, in order to understand the role of sedimentary, post-depositional and anthropogenic processes in the formation of the stratigraphy of the cave.

The micromorphological investigation highlights several microfacies associated with the finer-grained sediments. The sediments within the deposit is mainly allochthonous as evidenced by the abundance of aeolian quartz and remnants of leached soils, thus indicating erosion and transport into the cave. Moreover, the characterisation of the microfacies suggests runoff and standing water processes as main agents of the internal redistribution of material. This also includes, albeit to a lesser extent, phases of biological activity, as well as phases of relative surface stability and anthropogenic contributions. Anthropogenic inputs are mainly related to fire activity and food exploitation, such as charcoal, charred plant tissue, and burnt bones. Notwithstanding the extensive volume of sediments excavated during historical archaeological campaigns, especially in the mid-frontal sectors, results show that anthropogenic inputs are not restricted to specific areas within the cave, due to its dimensions, rather they are sporadically scattered across the microfacies.

How to cite: Mariani, G. S., Pieruccini, P., Susini, D., Forti, L., Mazzini, I., and Sardella, R.: Micromorphological insights within the Middle Pleistocene-Holocene cave sediment record of Grotta Romanelli, Italy., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16626, https://doi.org/10.5194/egusphere-egu24-16626, 2024.

Isotope analysis, particularly for the determination of δ13C and δ15N in archaeobotanical remains, is a recognized method within the field of archaeology. Until now, the primary focus of these analyses has been on archaeobotanical remains directly related to dietary practices. The significant impact of the Cistercian Order on the European agricultural landscape, and its far-reaching ecological consequences, has been well documented. However, the use of isotopic analysis for determining land-use based on present-day soils remains unexplored. The study at hand focuses on a Cistercian court, utilized from the 13th to the 15th century. The lands of this court, along with its surrounding regions, have been extensively surveyed. The isotopic analysis of the anthropogenically influenced soils is compared to approximately 400 archaeobotanical, soil, and sediment samples collected globally. The comparative analysis reveals the potential to ascertain through the presence of the C3 cycle and evidence of medieval fertilization, that the area was used for cereal cultivation and fertilization. The results of our study indicate that the medieval Cistercians employed the landscape primarily for grain production rather than pastoralism.

How to cite: Janovský, M., Ferenczi, L., and Trubač, J.: New stable isotope geochemical approach documents grain production and manuring in the High Middle Ages, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20000, https://doi.org/10.5194/egusphere-egu24-20000, 2024.

Climate variability, especially monsoonal rainfall, has significantly shaped habitable areas for human populations in South Asia in the past just as it does today. Instances of climate-driven social disruptions and population movements are evident worldwide, as evidenced for example in the Classic Maya and the Indus Valley Civilization (IVC). However, climate change can manifest in very different ways in terms of vegetation and fire regimes, with important implications for regional environmental histories as well as socio-political patterns. As such, it is essential to develop a comprehensive understanding of the intricate interplay between climate, vegetation, fire, and archaeological evidence relating to changes in settlement patterns and continuities. Insights derived from such studies offer a foundation to explore and comprehend present and future human-environment interactions.

Here we present multi-proxy time-series datasets derived from a 2.25-meter geological trench known as ‘Jankipura,’ located within the semi-arid Thar Desert. Jankipura, located near Didwana Lake, holds prehistoric importance, being surrounded by major archaeological sites in the Thar Desert. It is also a part of the Didwana Palaeolithic Complex, surrounded by the IVC, Jodhpura-Ganeshwar, and Ahar-Banas cultural regions. The chronology of the Jankipura trench is constructed based on four ¹⁴C AMS dates ranging from 183 to 4656 cal yr. BP, aligning with the Mature phase of the IVC – a period characterized by population migration and a severe reduction in settlement density. Our analysis encompasses measurements of sediment total organic and bulk carbon isotope (d¹³C_bulk) composition, alongside examinations of plant-wax molecular distributions (n-alkanes and fatty acids). Additionally, we analyzed the δ¹³C and δ²H values of long-chain n-alkanes (C₂₇, C₂₉, C₃₁, and C₃₃) and fatty acids (C₂₆, C₂₈, C₃₀, and C₃₂) extracted from the sediment samples.

Our study also involved the assessment of macro-charcoal concentrations (>125 µm, differentiating grass from wood) to reconstruct the climate-vegetation-fire relationships during and after a major period of disruption of the IVC. The findings highlight an dry phase between 4656 and 2932 cal yr. BP, characterized by a mixed C₃-C₄ vegetational landscape with limited fire episodes. A significant fire episode took place during the period from 2932 to 1960 cal yr. BP, suggesting dry conditions supported by abundant C₄ vegetation. Between 1960 and 183 cal yr. BP, three minor fire events occurred amid fluctuating rainfall conditions and a landscape dominated by mixed C₃-C₄ vegetation. The identified macro-charcoal predominantly comprised woody fragments over grass fragments. Notably, an increasing trend in isotope values, reaching its peak in macro-charcoal, is observed between 183 cal yr. BP and the present, signifying increased aridity compared to the mature phase of the IVC.

Although the study is based on a single trench, our observation of a weak relationship between vegetation and fire suggests that the reconstructed fire events may have originated from anthropogenic activities. This sheds light on the significance of vegetation, especially the utilization of wood, during the Mature phase of the IVC. We recommend generating more records from this region to better comprehend the spatio-temporal interaction of the IVC population with the environment.

How to cite: Jha, D., Blinkhorn, J., Schwab-Lavric, V., Zuccarelli Freire, V., Ilgner, J., Achyuthan, H., Boivin, N., Devra, R., Maezumi, S. Y., Gleixner, G., Roberts, P., and Petraglia, M.: Plant-wax biomarkers and their isotopes reveal complex relationships between climate, vegetation and fire during collapse of Indus Valley Civilization, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20312, https://doi.org/10.5194/egusphere-egu24-20312, 2024.

Understanding the historical changes in Relative Sea Level (RSL) and coastal responses in stable regions is crucial for unraveling the intricate relationship between natural dynamics and human adaptation. This interdisciplinary study seeks to explore the Holocene sea-level fluctuations in the stable area of Southern Latium, shedding light on how past societies adapted to coastal changes.
The study area, located in the historical Sinus Formianus, between the Fondi and Garigliano coastal plains, played a key role in ancient times. Formia, a strategic monitoring point for the Tyrrhenian Sea, was a thriving commercial hub during Roman occupation. During this period, the coastal stretch 
from Formia to Gaeta witnessed substantial urbanization, leaving behind well-preserved remnants visible today in submerged or semi-submerged coastal structures along the present shoreline.

This study reconstructs the Holocene morpho-evolution and RSL changes in the study area by creating a geodatabase following international guidelines for sea-level markers (SLMs). A comprehensive dataset of 52 SLMs was compiled from direct geoarchaeological measurements, stratigraphic and palaeoecological interpretations of new borehole data, and reinterpreting bibliographic information. Archaeological site selection involved analyzing bibliographic, cartographic, and video materials for ruins' details and dating. Additionally, public institutions provided access to an unpublished stratigraphic dataset from five deep boreholes drilled between Fondi and Formia plains in 2023. 
Three samples were collected from the stratigraphic columns of the analyzed boreholes in Formia Plain and dated using the radiocarbon dating technique. One sample, derived from a lagoonal deposit, presented an age exceeding the dating technique's accuracy range and older than 54 ka BCE. Despite this, the dating provided valuable information on the initiation of backshore formation. The other two dated samples, derived from a second drilling and collected inside layers of peat deposits, were interpreted as Terrestrial Limiting Points (TLPs) defining an upper limit of -4.20 m MSL for the RSL position at about 7.5 ka BP.
Accordingly, based on the collected data, between 8.0 and 7.5 ka BP, the sea level in the study area rose from -23 to -5 m at a rate of 25 mm/yr. Subsequently, the rate slowed to less than 5 mm/yr, stabilizing at its current position. In particular, the results coming from the geoarchaeological surveys suggest that the local sea level during the Roman period (I century BCE) was no higher than - 0.55 ± 0.29 m MSL. 
Overall, the RSL data included in the geodatabase highlights the tectonic stability of this sector during the last 2.0 ka, testified by the position of the SLMs in accordance with the GIA models and supported by the determination of average vertical ground movements rates of -0.017 ± 0.23 mm/yr.

Finally, the interplay between new data from geoarchaeological surveys, bibliographic sources, and LiDAR-based geomorphological analysis allowed the creation of a paleogeographic scenario for the study area in the 1st century CE. This highlights the significant landscape modifications induced by anthropic activities during that period.

How to cite: Caporizzo, C., Aiello, G., Amato, V., Aucelli, P. P. C., Barra, D., Gionta, A., Corrado, G., Mattei, G., Pappone, G., Parisi, R., Petrosino, P., Schiattarella, M., and Vacchi, M.: Holocene relative sea-level changes and coastal dynamics in Southern Latium, Italy: an interdisciplinary investigation , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21345, https://doi.org/10.5194/egusphere-egu24-21345, 2024.

The allocation of metabolised carbon (C) between soil microbial growth and respiration, i.e. C use efficiency (CUE) is crucial for SOC dynamics. The pH was shown to be a major driver of microbial CUE in agricultural soils and therefore, management practices to control soil pH, such as liming, could serve as a tool to modify microbial physiology. We hypothesised that raising soil pH would alleviate CUE-limiting conditions and that liming could thus increase CUE, thereby supporting SOC accrual. This study investigated whether CUE can be manipulated by liming and how this might contribute to SOC stock changes. The effects of liming on CUE, microbial biomass C, abundance of microbial domains, SOC stocks and OC inputs were assessed for soils from three European long-term field experiments. Field control soils were additionally limed in the laboratory to assess immediate effects, accounting for lime-derived CO₂ emissions (δ13C signature). The shift in soil pH_H2O from 4.5 to 7.3 with long-term liming reduced CUE by 40%, whereas the shift from 5.5 to 8.6 and from 6.5 to 7.8 was associated with increases in CUE by 16% and 24%, respectively. The overall relationship between CUE and soil pH followed a U-shaped (i.e. quadratic) curve, implying that in agricultural soils CUE may be lowest at pH_H2O = 6.4. The immediate CUE response to liming followed the same trends. Interestingly, liming increased microbial biomass C in all cases. Changes in CUE with long-term liming contributed to the net effect of liming on SOC stocks. Our study confirms the value of liming as a management practice for climate-smart agriculture, but demonstrates that it remains difficult to predict the impact on SOC stocks due its complex effects on the C cycle.

How to cite: Schroeder, J., Damatirca, C., Bölscher, T., Chenu, C., Elsgaard, L., Tebbe, C. C., Skadell, L., and Poeplau, C.: Liming effects on microbial carbon use efficiency and its potential consequences for soil organic carbon stocks, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-105, https://doi.org/10.5194/egusphere-egu24-105, 2024.

With promising methods such as ultrahigh-resolution mass spectrometry (FT ICR MS), soil scientists have more opportunity than ever to gain a comprehensive picture of the composition and transformation of soil organic matter (SOM).  With soils as central mediators for carbon capture and storage this understanding is key when it comes to tackling major challenges, such as climate change and soil health. However, as novel techniques are often imported from other scientific fields, the evaluation and interpretation of data with regard to the heterogeneous pedosphere often remains a major challenge. For FT ICR MS, several commonly used indices were developed from empirical observations of the deep ocean. While these indices seem statistically transferable from ocean DOM to the terrestrial realm, there is legitimate concern that no causality ultimately ensures this applicability. Indices are needed that allow interpretation of the data from a conceptual perspective. Viewing SOM as a thermodynamically driven mediator of energy fluxes in the soil food web provides an opportunity to put a foot on the ground of data analysis with more general applicability. We aim to show that bioenergetic and thermodynamic molecular indices allow a better understanding of soil organic matter transformation by comparing FT ICR MS samples from complex, mixed sources and single source endmembers.

We investigated the molecular composition of stream DOM and soil leachates along a biome gradient between alpine meadow and alpine steppe, including a chronosequence of degradation in the southern Tibetan Nam Co watershed. Our results suggest a certain match of commonly used DOM molecular indices, such as the ‘island of stability‘, the ‘degradation index‘ and the ‘terrestrial index‘, applied to marine settings for terrestrial DOM and SOM. However, when comparing SOM and DOM phase transitions within endmember sources, we noted inconsistencies. In contrast, indicators representing the bioenergetics of organic matter composition, such as the ‘nominal oxidation state of carbon’ and the ‘Gibbs free energy for carbon oxidation’, show good agreement for the key phase transition between SOM and DOM. These results provide reasonable evidence in line with conceptual understanding, such as more oxidised DOM and SOM in degraded areas and generally less oxidised molecular formulae in mainly allochthonous stream DOM compared to extracted SOM. Our data support the notion that bioenergetic and thermodynamic indicators may be a way forward to better understand the complex nature of organic matter transformation in soils with FT ICR MS. These indicators can serve as important building blocks for molecular fingerprinting.

How to cite: Maurischat, P., Seidel, M., Donnerhack, O., Liebmann, P., and Guggenberger, G.: Thermodynamic indicators decipher the molecular composition of organic matter in phase transition, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1301, https://doi.org/10.5194/egusphere-egu24-1301, 2024.

Chemical quality of plant residues, which are the source of dissolved organic C (DOC), determine the molecular structure, notably functional group polysaccharides in DOC, and the origins of DOC-polysaccharide, which transitioned from plant- to microbial-derived as decomposition progressed. The microbial-derived DOC-polysaccharides contribute to soil organic C (SOC) stabilization, but what factor associated with the residue chemical quality regulates the origin of the DOC-polysaccharides remains unknown. Balanced DOC and dissolved N (DN) (DOC-and-DN) stoichiometry of microbial substrates as indicated by DOC-to-DN ratio enhances microbial C use efficiency (CUE). The CUE indicates the production of microbial-derived DOC compounds. We hypothesized that DOC-and-DN stoichiometry in soils receiving plant residues was a key factor controlling the origin of DOC-polysaccharides. The objectives of this study were to determine 1) DOC-to-DN ratio during decomposition, 2) relationships of DOC-to-DN ratio and microbial metabolic quotient (qCO₂ - inverse of CUE), and 3) relationships of qCO₂ and DOC-to-DN ratio with DOC-polysaccharides. This study employed data from year 13 of a long-term field experiment on the effect of annual application of varying quality residues on decomposition processes in sandy soils. During the early stage of decomposition (week 0-2), DOC-to-DN ratio of N-rich groundnut stover (GN) residue decreased, in contrast to low-N rice straw (RS), and dipterocarp leaf litter (DP) and medium-N tamarind leaf+petiole litter (TM). During the intermediate stage (week 2-8), GN and RS had increasing ratios, as opposed to DP and TM. Groundnut-treated soil had lower average ratio (6.8±2.6) than TM, RS and DP (10.7±4.4, 12.1±5.4, 14.1±7.2, respectively). Positive influences of the ratio on qCO₂ in the three medium-to-low-N soils (R² = 0.60** - 0.74**) indicated that the ratio had significant control on the CUE. The qCO₂, in turn, had significant influence (non-linear relationship) on DOC-polysaccharides (R² = 0.30*).  In the early stage (high qCO₂)_, it decreased (indicating the increase of CUE) corresponding to the decreases in DOC-polysaccharides indicating that these were plant-derived. The qCO₂ decreased further beyond the threshold of 0.00026 mg CO₂-C kg^-1 microbial biomass C h^-1 whichmarked the beginning of the intermediate stage (low qCO₂), corresponding to an increase in microbial-derived DOC-polysaccharides.  This increase signified the change in their origin. Negative influence of DOC-to-DN ratio on DOC-polysaccharides (R² = 0.36*) during the intermediate stage showed that the increased ratios caused the decreases in DOC-polysaccharides. Our results identified DOC-and-DN stoichiometry in residues-treated soils as a prominent factor controlling the origin of the DOC-polysaccharides. Imbalanced DOC-and-DN stoichiometry in low-N residues, i.e., higher DOC-to-DN ratios than microbial biomass C-to-N ratios, brought about the decrease in microbial-derived DOC-polysaccharides during the later stage. Soil management via organic inputs requires careful consideration of changes in DOC-and-DN stoichiometry which can affect SOC accumulation.

How to cite: Poosathit, R. and Vityakon, P.: Stoichiometry of dissolved organic matter controls the origin of polysaccharides in dissolved organic carbon in sandy soils receiving contrasting-quality plant residues, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2590, https://doi.org/10.5194/egusphere-egu24-2590, 2024.

Microbial carbon use efficiency (CUE) is a vital physiological parameter in assessing soil carbon turnover. Yet, how microbial communities with distinct trophic strategies regulate soil microbial CUE has remained elusive. Based on the oligotrophic: copiotrophic framework, we here explored the role of microbial taxa with different trophic strategies in mediating microbial CUE (determined by a ¹³C-labeling approach) along the vegetation primary succession in the Hailuogou glacier retreat area of the southeastern Tibetan Plateau. Soil microbial CUE ranged from 0.54 to 0.72 (averaging 0.62 ± 0.01 across all samples), increasing markedly along the vegetation succession. Microbial assemblies with distinct trophic strategies were crucial regulators of soil microbial CUE. Specifically, microbial CUE increased with microbial oligotroph: copiotroph ratios, with oligotroph-dominated stages having a higher microbial CUE than copiotroph-dominated ones. The prevalence of oligotrophic members would therefore be linked to the high soil microbial CUE at late successional stages. Given that oligotrophs predominate in soils with more recalcitrant carbon and because of their higher microbial CUE, we speculate that oligotrophs are likely to promote carbon sequestration in soils. In addition, the responses of soil microbial CUE to fungal oligotroph: copiotroph ratios were stronger than to bacterial ones. Fungal taxa may play a particularly pronounced role in shaping microbial CUE relative to bacterial members. Overall, our results highlighted close associations between microbial trophic strategies and CUE and provide direct evidence regarding how microbial trophic strategies regulate soil microbial CUE. This study is a significant step forward for elucidating the physiological mechanisms regulating microbial CUE and has significant implications for understanding microbial-mediated carbon cycling processes.

How to cite: Ma, S., Zhu, W., Wang, W., Li, X., Sheng, Z., and Wanek, W.: Microbial assemblies with distinct trophic strategies drive changes in soil microbial carbon use efficiency along vegetation primary succession in a glacier retreat area of the southeastern Tibetan Plateau, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3903, https://doi.org/10.5194/egusphere-egu24-3903, 2024.