HS5.3.3 | Land and Water Interactions: Evaluating the Impacts of Land Use Changes on Water Resources, Ecosystems, and Food Systems
Fri, 10:45
EDI PICO
Land and Water Interactions: Evaluating the Impacts of Land Use Changes on Water Resources, Ecosystems, and Food Systems
Convener: Giulio CastelliECSECS | Co-conveners: Sofie te Wierik, Tommaso PacettiECSECS
PICO
| Fri, 02 May, 10:45–12:30 (CEST)
 
PICO spot 4
Fri, 10:45

PICO: Fri, 2 May | PICO spot 4

PICO presentations are given in a hybrid format supported by a Zoom meeting featuring on-site and virtual presentations. The button to access the Zoom meeting appears just before the time block starts.
Chairpersons: Giulio Castelli, Sofie te Wierik, Tommaso Pacetti
10:45–10:50
10:50–11:00
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PICO4.1
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EGU25-21686
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solicited
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On-site presentation
Matti Kummu

Despite the global population exceeding eight billion, food production per capita is globally higher than ever. However, this achievement has led to significant environmental impacts, with agriculture being the largest sector contributing to the transgression of many planetary boundaries, including biogeochemical flows, biosphere integrity, land system changes, and freshwater changes. To move towards more sustainable food futures, several opportunities exist, such as reducing food loss, upcycling by-products into livestock and aquaculture feeds, implementing double cropping systems, and developing cultivated meat alternatives.
Here first a global overview of the multiple pressures agricultural practices apply on Earth systems is provided, with a focus on their impact on water and land resources, biodiversity, and nutrient pollution. The main emphasis is, however, to synthesize the potential of various interventions that could mitigate these pressures and promote sustainability. These insights are crucial for understanding the intricate links between land use, water systems, and food production,and for identifying effective and equitable future resource management strategies.

How to cite: Kummu, M.: Sustainable food futures: opportunities to alleviate pressure on Earth System, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21686, https://doi.org/10.5194/egusphere-egu25-21686, 2025.

Land-Water interactions in agricultural systems
11:00–11:02
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PICO4.2
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EGU25-581
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ECS
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On-site presentation
Moussa Ait el kadi, Lhoussaine Bouchaou, Mohammed El hafyani, Soumia Gouahi, Brahim Meskour, Victor Fernandez, Chaimae Aglagal, and Mohammed Hssaisoune

While Morocco faces extreme water shortage (<500m3/cap), agricultural development policies intend to improve the agri-business sector focusing on global competitiveness and export-oriented crops. However, in vulnerable environments (e.g Souss basin) these policies contributed to exacerbation of the water crisis. Based on land use dynamics, water resources monitoring and field interviews with farmers and rural water users, our study draws a state of art of the situation and discusses the findings. Despite the fact of some short-lasting gain from these policies, land use data indicates an expansion of irrigated land from 618.96 sq km in 2002 to 1413.3 sq km in 2012 due to incentives from Green Morocco Plan (GMP). As a result of increase of water demand for irrigation coupled with extreme drought periods, the data of groundwater shows a dramatic depletion of groundwater, the strategic resource for livelihoods and drought resilience. Furthermore, learning from the field reveals the inconvenience of intensive export-oriented agriculture in a drought prone environment. In addition, farmers' perspectives and adaptation strategies indicate the importance of participatory and community-based management of natural resources. Therefore, the study demonstrates the importance of inclusion of socio-environmental vulnerabilities in agriculture development planning.

How to cite: Ait el kadi, M., Bouchaou, L., El hafyani, M., Gouahi, S., Meskour, B., Fernandez, V., Aglagal, C., and Hssaisoune, M.: Impact of agricultural development policies on land use, water resources and rural livelihoods in the semi-arid environment of Souss Basin in Morocco., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-581, https://doi.org/10.5194/egusphere-egu25-581, 2025.

11:02–11:04
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PICO4.3
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EGU25-21033
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ECS
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Highlight
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On-site presentation
Iolanda Borzì, Francesco Gregorio, Giovanni Randazzo, and Stefania Lanza

This study presents a hydrogeological assessment of the impacts of land use changes and climate variability on groundwater resources in the Licata plain, Sicily, with a particular focus on agricultural irrigation. We integrate long-term hydroclimatic data and current land use patterns to investigate the complex interactions between surface and subsurface water systems over recent decades.

The Licata plain is characterized by an unconfined to semi-confined alluvial aquifer developed in Quaternary deposits, which serves as a critical water source for local farmers. Using extensive rainfall records and streamflow data from the Imera River, we analyze long-term hydrological trends and their implications for groundwater recharge and availability for irrigation. High-resolution land use maps are utilized to assess the spatial distribution of agricultural activities and their influence on groundwater demand and local hydrology.

We integrate these datasets into a coupled surface-groundwater model to simulate hydrological processes and infer groundwater dynamics under changing land use and climate scenarios. The model is calibrated using available streamflow records and validated against limited piezometric data points.

The land use analysis identifies critical zones of agricultural intensification, highlighting areas of increased water demand and altered infiltration patterns. Our findings indicate that local farmers heavily rely on groundwater resources, especially during periods of drought or low rainfall, as evidenced by recent water scarcity events in Sicily.

This research provides a robust framework for assessing groundwater vulnerability in Mediterranean coastal aquifers subject to rapid land use transformation and climate uncertainty, with a specific focus on agricultural water use. Our findings offer valuable insights for water resource managers and policymakers in Licata, emphasizing the need for adaptive strategies that consider both sustainable agricultural practices and climate resilience. Moreover, this study underscores the importance of establishing comprehensive groundwater monitoring networks to enhance future assessments and support informed decision-making for agricultural water management.

How to cite: Borzì, I., Gregorio, F., Randazzo, G., and Lanza, S.: Assessing the Impacts of Land Use Change and Climate Variability on Groundwater Resources for Agricultural Irrigation in Licata, Sicily, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21033, https://doi.org/10.5194/egusphere-egu25-21033, 2025.

11:04–11:06
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PICO4.4
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EGU25-10144
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ECS
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On-site presentation
Heindriken Dahlmann, Lauren Seaby Andersen, Sibyll Schaphoff, and Dieter Gerten

Agricultural areas are increasingly experiencing green water stress – i.e. soil moisture limiting crop growth – due to rising water demands of an expanding world population as well as climate change. While irrigation has the potential to mitigate this stress, its effective implementation is often challenged by blue water scarcity and lack of irrigation infrastructure. In this study, we apply a newly developed plant physiological index of green water stress, modeled by the global dynamic vegetation model LPJmL, that accounts for both soil moisture limitation and atmospheric water demand of major agricultural crops. By analyzing the spatial-temporal patterns of green water stress globally and over the past decades, we identify current hotspots of green water stress which are mainly located in India and Pakistan, Southern Europe, northern Sub Saharan Africa, southern Africa and Mexico and are characterized by a high seasonal variability. We also map blue water stress relating to human water use (withdrawals for households, industry and agriculture) and demonstrate the extent to which sufficient blue water resources are available to buffer green water stress in agriculture. By focusing on the interconnectedness between green and blue water stresses through the implementation of irrigation, this study contributes to a more profound understanding of sustainable water use in agriculture.

How to cite: Dahlmann, H., Seaby Andersen, L., Schaphoff, S., and Gerten, D.: Spatio-temporal patterns of green and blue water scarcities in agriculture, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10144, https://doi.org/10.5194/egusphere-egu25-10144, 2025.

11:06–11:08
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PICO4.5
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EGU25-12089
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On-site presentation
Bano Mehdi-Schulz, Edberto Moura Lima, Claudine Egger, and Gaube Veronika

In agricultural catchments, the decisions made by farmers regarding crop choices and field management practices influence both water flow paths through the landscape and the amounts of reactive nitrogen (N) applied to fields. Agent-based models (ABMs) capture regionally specific, complex, and dynamic interactions between farmers and natural systems across multiple scales, enabling the simulation of physical landscape changes. In this study, we applied a novel methodology using an ABM to generate annual land use layers to inform a hydrological model. This approach allows us to spatially identify specific crops contributing to excess nitrogen flows in the landscape and into water bodies. Additionally, we link the temporal sequence of crops within their crop rotations to weather patterns, enabling us to examine nitrogen transport pathways under future change scenarios. We used the SECLAND ABM to inform the SWAT ecohydrological model of annual land use change at the field scale.

Using SECLAND, three agricultural land use scenarios were developed: a business-as-usual (BAU) scenario, an extensification scenario (based on SSP1), and an intensification scenario (based on SSP5). We integrated the respective annual land use layers derived from the ABM into SWAT, with and without climate change scenarios, to quantify the resulting impacts on crop yields, water balance components, nitrogen concentrations in surface flows, nitrogen leaching, and nitrogen in groundwater.

The ABM results for the BAU scenario over the next 35 years show a decrease in the number of active farms, accompanied by a loss of agricultural areas. The results also indicate a transition toward organic farming and a shift in intensity toward extensification. In all land use scenarios, less corn is grown. As well, the area of forested land increases in the future.

For all three land use scenarios, implementing the land use layers with their annual crop rotations in SWAT led to significant differences in nitrogen losses (kg/ha) to surface and subsurface water bodies, compared to using a static land use approach. All three land use scenarios consistently showed lower nitrogen losses per area to the environment, particularly for crops requiring high levels of nitrogen fertilizer (e.g., corn and winter rapeseed).

When the land use scenarios were implemented in conjunction with climate change simulations in SWAT, lower N loads in lateral flow and groundwater was simulated, and hence in reduced nitrogen losses per area. Implementing crop rotations in the SWAT model also reduced the number of water and nitrogen stress days for the crops.

Our findings underscore the importance of including detailed spatial crop rotations when assessing regional water quality, particularly in conjunction with climate change scenarios. Furthermore, we found that using static land use in hydrological modeling generally leads to an overestimation of nitrogen losses, especially from crops with high fertilizer applications.

How to cite: Mehdi-Schulz, B., Moura Lima, E., Egger, C., and Veronika, G.: Quantifying nitrogen flows from agricultural land using an ABM to inform future land use change for ecohydrological modelling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12089, https://doi.org/10.5194/egusphere-egu25-12089, 2025.

11:08–11:10
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PICO4.6
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EGU25-12227
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On-site presentation
Gang Zhao, Bin Chen, Linjia Yao, and Qiang Yu

China faces a multifaceted challenge in ensuring food security amid escalating constraints on cropland and water resources. As the nation strives for self-sufficiency in food production, the imperative to maximize crop yields within limited land and water availability intensifies, particularly concerning the sustainable management of groundwater resources. This study investigates how China can balance short-term food production gains with the long-term sustainability of groundwater by optimizing irrigation practices and strategically navigating food import policies, with a focus on the three major staple crops: wheat, rice, and maize.

Intensive agricultural systems, especially in water-scarce regions such as the North China Plain, Xinjiang, and Inner Mongolia, are heavily reliant on groundwater extraction. This dependence poses significant risks of environmental degradation, including groundwater depletion, land subsidence, and reduced aquifer recharge, threatening both agricultural productivity and regional ecosystems. To address these issues, we conducted extensive field-based experiments across China from 2016 to 2020, encompassing 237 site-years of data. These experiments systematically varied irrigation practices to calibrate the Agricultural Production Systems sIMulator (APSIM) model, ensuring an accurate representation of regional agricultural dynamics and groundwater interactions.

Utilizing the calibrated APSIM model, we simulated irrigation demand and crop yields for wheat, rice, and maize under 125 different irrigation strategy combinations (considering both volume and timing) across baseline conditions and four Shared Socioeconomic Pathways (SSP) climate change scenarios. Additionally, we integrated Gravity Recovery and Climate Experiment (GRACE) satellite data to assess the availability and trends of groundwater resources across different regions, providing a comprehensive spatial analysis of water sustainability.

Our findings identify critical regions where strategic adjustments in irrigation management can significantly enhance food production while preserving groundwater resources. Specifically, optimizing irrigation timing to align with crop water demand and implementing water-saving technologies emerged as effective strategies to reduce groundwater extraction. Under the four SSP climate change scenarios, irrigation demand and crop yields exhibited varying responses, highlighting the necessity for adaptive management practices tailored to specific socioeconomic and climatic futures. In addition to optimizing irrigation, our study emphasizes the importance of a balanced food import policy to alleviate domestic water consumption in food production. By strategically importing certain food commodities, China can reduce the pressure on its limited water resources, thereby enhancing overall water sustainability. This approach complements domestic irrigation improvements and supports the cultivation of wheat, rice, and maize by ensuring that water-intensive demands are managed through a combination of local efficiency and global resource allocation.

This research underscores the importance of adopting integrated water management and strategic food import practices to ensure the long-term sustainability of China’s food production systems. The results provide actionable insights for policymakers, facilitating the design of agricultural and trade strategies that effectively balance the maintenance of food security with the preservation of essential groundwater resources for future generations. By transitioning from short-term yield maximization to sustainable irrigation management and informed food import policies, China can secure its food future while safeguarding its critical water resources and environmental integrity.

How to cite: Zhao, G., Chen, B., Yao, L., and Yu, Q.: From Short-Term Gains to Long-Term Sustainability: Rethinking Irrigation Strategies and Food Import Policies for Long-Term Sustainability, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12227, https://doi.org/10.5194/egusphere-egu25-12227, 2025.

Landscape manangement and water-related ecosystem services
11:10–11:12
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PICO4.7
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EGU25-8548
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On-site presentation
Landscape Restoration for Ecosystem Resilience Requires a New Agenda: Turning Carbon into the Engine for Watering the Earth & Cooling the Planet
(withdrawn)
David Ellison
11:12–11:14
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PICO4.8
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EGU25-9747
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On-site presentation
Maria J. Santos and the IPBES Nexus Assessment Water team

The recently approved and published IPBES Nexus Assessment, focuses on the interactions and interlinkages between biodiversity, water, food, health and climate. This assessment, requested by member states signatory to IPBES, defines nexus approaches, scenarios for nexus interactions and response options to each of the nexus elements with particular focus on cascading effects beyond a single nexus element. Within this context, we developed and examined the response options for water and their percolation to the other nexus elements. In this presentation, we will show (i) our process to identify the water response options which included multiple knowledge systems, (ii) their evaluation through assessing enablers and barriers, feasibility, context and scale and governance, and (iii) the robustness of our knowledge on the effectiveness of these response options to deliver on water quantity and quality. Currently, ~80% of humanity’s freshwater demand is used to meet food production, 75% of the global population in 2005 is dependent on forest for accessible freshwater, and at least 50 diseases are attributable to poor water supply, quality and sanitation. We find that the 15 response options that we examined cut across more than two nexus elements, yet we found no response option that would deliver benefits to all nexus elements concurrently. Particularly, stronger or more robust trade-offs emerge when water, biodiversity and food systems are considered. Future scenarios show that a nature positive nexus will concurrently deliver on all nexus elements, and for water specifically, the strongest impacts emerge if food systems are prioritized as well as nature overexploitation.

How to cite: Santos, M. J. and the IPBES Nexus Assessment Water team: Water-related processes: IPBES Nexus assessment Options for delivering sustainable approaches to water, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9747, https://doi.org/10.5194/egusphere-egu25-9747, 2025.

11:14–11:16
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PICO4.9
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EGU25-12516
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ECS
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On-site presentation
Jerome El Jeitany, Tommaso Pacetti, Boris Schröder, and Enrica Caporali

The configuration of landscapes plays a pivotal role in shaping water yield dynamics, influencing the spatial and temporal distribution of hydrological patterns within heterogeneous catchments. Employing the SWAT+ model, three land-use scenarios—agricultural, vegetative, and pasture—were simulated over 20 years to isolate the effects of landscape arrangement while maintaining constant land cover proportions. Spatial and temporal analyses of water yield patterns were conducted using space-time cubes and emerging hotspot analysis, while multinomial logistic regression assessed the influence of soil hydrological groups, proximity to land-use transitions, and landscape connectivity. The results suggests that despite minimal effect on the total water yield governed by landscape proportions, landscape configuration impacted the spatial distribution and intensity of water yield hotspots. The agricultural scenario demonstrated persistent and intensifying hotspots, attributed to fragmentation and proximity to land-use transitions, with hotspots covering 15% of the area. In contrast, vegetative and pasture scenarios reduced hotspot intensity by 12% and 9%, respectively, demonstrating more uniform water yield distributions. Hydrological group analysis highlighted the critical role of soil properties, with Group C areas exhibiting a 20% higher likelihood of transitioning from cold to hot spots compared to Group B. From a management perspective, this study stresses the need of integrating landscape configuration into watershed planning. Strategies such as preserving vegetative corridors and implementing buffer zones within agricultural patches can mitigate yield variability and optimize water-related ecosystem services. The research aims at developing further adaptive landscape management approaches that address hydrological challenges in such dynamic land use agricultural watershed.

How to cite: El Jeitany, J., Pacetti, T., Schröder, B., and Caporali, E.: Evaluating Landscape Configuration Impacts on Water Yield Dynamics in Heterogeneous Catchments, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12516, https://doi.org/10.5194/egusphere-egu25-12516, 2025.

11:16–11:18
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PICO4.10
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EGU25-16978
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ECS
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On-site presentation
Marco Lompi, Nikolas Galli, Enrica Caporali, and Maria Cristina Rulli

Flood-Regulating Ecosystem Services (FRES) are widely used to assess the capacity of the environment to retain water during a storm, mitigate runoff and ultimately reduce flood risks within a river basin. FRES are commonly evaluated by assuming a change in land use to compare differences in the runoff of two scenarios: a baseline, representing actual conditions, and a scenario in which the land use of the environment is changed to barren ground. Agricultural areas contribute to flood regulation as they have a lower runoff with respect to barren or urbanised landscapes. However, methodologies to evaluate FRES in agricultural areas usually do not consider the variations in soil moisture that result from crop rotation throughout the year. Moreover, land use data typically used in such assessments describe with little or no detail the type of crop present in a given area.

To overcome these limitations, we introduce a methodology to evaluate seasonal FRES with two main research questions: i) is there a seasonality in the FRES of small agricultural river basins? ii) can different soil moisture conditions due to different crops have a diverse flood-regulating potential at the river basin scale?

The proposed approach is based on coupling two hydrological models: Watneeds, an agro-hydrological model that estimates daily soil moisture based on agricultural water demand, and Mobidic, a fully distributed rainfall-runoff model. Mobidic uses the soil moisture conditions derived from Watneeds as the initial state to simulate flood hazards during extreme storm events.

The methodology is applied in the upper Ombrone Grossetano river basin (Tuscany, Central Italy), where agricultural land constitutes a great part of the river basin area. The study used gridded datasets and ground observations for model calibration and analysis. Specifically, the Chirps dataset was bias corrected using ground observations and supported hydrological balance calculations in Watneeds. In contrast, rain gauge data from the Regional Hydrological Service were used to perform frequency analyses of extreme rainfall events and derive the rainfall quantiles modelled in Mobidic.

The results reveal that different crops produce distinct soil moisture conditions under identical weather patterns, influencing flood hazards in varying ways. FRES show a seasonality, with the maximum value at the end of the growing season, especially for the tributaries of the river with an area generally less than 60 km2. The FRES supplied by the agroecosystem each month is compared with the FRES demand, i.e. the monthly average peak discharge. The results demonstrate that agricultural practices and crop scenarios can result in diverse flood responses depending on the season, offering valuable insights for flood risk management in small agricultural river basins. They suggest that policies governing crop selection, irrigation schedules, and crop calendars should also consider their potential impacts on flood regulation.

This research is part of the FLORAES project, funded by the Premio Florisa Melone 2023, an initiative by the Italian Hydrological Society to foster independent research and collaboration among young Italian hydrologists.

How to cite: Lompi, M., Galli, N., Caporali, E., and Rulli, M. C.: Evaluating the influence of crop seasonality on flood-regulating ecosystem services in small river basins, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16978, https://doi.org/10.5194/egusphere-egu25-16978, 2025.

11:18–11:20
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EGU25-14454
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ECS
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Virtual presentation
Mariela Estefanía Nava Vélez, René Ventura Houle, and Glenda Nelly Requena Lara

Forest ecosystems, recognized for their ecohydrological importance, play a crucial role in regulating water resources, especially in arid and semi-arid regions of developing countries. The San Fernando-Soto la Marina Basin, located in northeastern Mexico, is a region of high significance for agricultural and livestock activities in the country. It is part of the Burgos gas region and has potential for shale gas exploration. Additionally, rapid changes in land use have significantly impacted the region's hydrological processes. Therefore, proper water management is key to conserving natural resources, fostering economic development, and ensuring water security. This study evaluates the seasonal water yield in the basin, highlighting the contribution of shrublands to the region's hydrological sustainability.

The Seasonal Water Yield (SWY) model of InVEST was used, integrating climatic, land use, soil type, and topographic data. Curve Number (CN) values were calculated to assess infiltration and runoff potential. Key parameters such as actual evapotranspiration (AET), quickflow, and baseflow were analyzed across different land use types, with a focus on forested and agricultural areas. Geospatial data were also integrated to model hydrological responses to land use and land cover changes in the basin.

The results showed that agricultural areas, covering 16.83% of the basin, as well as urban areas, had high CN values (average of 77), indicating limited infiltration and higher runoff. In contrast, oak-pine and cloud forests exhibited low CN values (0–40), promoting higher infiltration and water retention. However, these forests occupy only 5.43% of the basin's surface. Semi-arid shrublands showed moderate yields but contributed the largest water volume due to their extensive coverage (22.07% of the basin).

Shrublands and other forested areas in the San Fernando-Soto la Marina Basin are essential for mitigating surface runoff, enhancing basins recharge, and maintaining water availability. Their conservation and restoration should be prioritized to ensure ecohydrological sustainability. This study provides a foundation for integrated water management strategies, emphasizing the need for public policies that balance land use changes with water resource conservation.

How to cite: Nava Vélez, M. E., Ventura Houle, R., and Requena Lara, G. N.: Seasonal Water Yield in a Basin with Semi-Arid Ecosystems of Northeastern Mexico, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14454, https://doi.org/10.5194/egusphere-egu25-14454, 2025.

Watershed scale modelling and the Water-Energy-Food-Ecosystems (WEFE) Nexus
11:20–11:22
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PICO4.11
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EGU25-12034
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ECS
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On-site presentation
Claudia Romero Hernández, Javier Rodrigo Ilarri, María Elena Clavero Rodrigo, and Sergio Salazar Galán

This study examines the urban sprawl of Valencia and its metropolitan area over the past decades, focusing on the conversion of agricultural land into urban areas. The study is done using the WEI composite indicator which provides a quantitative framework for assessing the environmental value of the territory over time. To calculate the WEI values, official databases such as the Land Use Information System of Spain (SIOSE) and the World Settlement Footprint (WSF) were utilized.

The study's findings indicate that the growing urbanization of the Valencia metropolitan area has exacerbated the impacts of natural disasters, particularly flooding. Urban expansion in protected areas, such as the Albufera Natural Park, has heightened the risks associated with climate change by increasing soil impermeability and reducing water absorption capacity, thereby increasing vulnerability to extreme events. The analysis highlights how changes in land use and land cover (LULC) have intensified these impacts, as evidenced during the DANA event in October 2024. These findings emphasize the urgent need for sustainable urban planning and improvements in drainage infrastructure to mitigate flood risks, safeguarding both urban areas and natural spaces against future catastrophic events.

How to cite: Romero Hernández, C., Rodrigo Ilarri, J., Clavero Rodrigo, M. E., and Salazar Galán, S.: Land Use Land Change analysis over time using the WEI index under climate change conditions: Application to Valencia Metropolitan Area (Spain), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12034, https://doi.org/10.5194/egusphere-egu25-12034, 2025.

11:22–11:24
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PICO4.12
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EGU25-17560
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On-site presentation
Navneet Kumar, Bernhard Tischbein, and Stefan Schneiderbauer

Land-use change significantly impacts water balance components by altering the distribution and movement of water within a basin. The Upper Kharun Catchment (UKC) in India represents an area with significant recent land-use changes, namely by substantial population growth, urban expansion, industrialization, and changes in irrigation practices such as extension and intensification. This study investigates the impact of such modifications in land-use on water balance components using the Soil and Water Assessment Tool (SWAT) exemplified in the UKC. Therefore, we produced and analyzed land use maps for the time periods of 1991, 2001, 2011 and 2021. Our research findings indicate that the increasing amount of groundwater pumped for irrigation is the primary factor contributing to reduced groundwater flow into streams, which in turn leads to a decrease in discharge and overall water supply especially in drought periods. Conversely, annual surface runoff has significantly increased due to the expansion of built-up areas due to surface sealing over the decades in the relevant parts of the study area. Comparing the effects at catchment and sub-catchment levels highlights the importance of choosing the appropriate spatial scale for water management activities. At the catchment scale, the impact of land-use change on the water balance is small because different effects, such as urbanization and the intensification of agriculture, tend to offset each other. However, at the sub-catchment level, where local land-use dynamics are more pronounced, the effects of land-use change become evident. The combination of remote sensing techniques and hydrological modeling has allowed for identifying hotspot areas with changes in land use, which significantly affect on the components of the water balance. These areas should be prioritized for enhanced modeling and monitoring as basis for the development of water management strategies that can mitigate negative impacts on the water balance and in turn on improving the livelihood of the population as well as towards conserving ecosystems’ functioning. However, it's important to view these sites not in isolation but as part of an integrated approach for coordinated water management throughout the entire basin.

How to cite: Kumar, N., Tischbein, B., and Schneiderbauer, S.: Impact Assessment of Land-use change on water resources using the Soil and Water Assessment Tool (SWAT), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17560, https://doi.org/10.5194/egusphere-egu25-17560, 2025.

11:24–11:26
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PICO4.13
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EGU25-20496
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On-site presentation
Nicole Tatjana Scherer, Prof. Dr. Markus Disse, and Dr. Jingshui Huang

As a result of climate change, heatwaves, droughts and extreme precipitation events are becoming more frequent. These lead to drought damage in forests and crop failures, but also to erosion and flooding. In addition to climate change, changes to the landscape caused by humans (drainage, soil compaction and sealing) are also affecting the natural landscape water balance. This has a negative impact on people and ecosystems and can lead to competing demands and conflicts between different sectors.

A climate-resilient landscape water balance is essential for sustainable water resource management. The WEFE (Water-Energy-Food-Ecosystem) nexus offers an integrated and coordinated approach across all sectors to reduce trade-offs and increase the efficiency of the entire system through synergies.

The overall objective of the study is to provide decision-makers with a planning framework to assess the impact of different adaptation measures on the WEFE sectors under climate change scenarios. The model framework is based on a system of indicators. The indicators themselves are derived from the results of the ecohydrological SWAT+ model and integrated into an assessment framework by the stakeholders through individual weighting.

The Upper Main catchment in Bavaria, Germany, is used as case study. The varying distribution of precipitation and the low storage capacity of the soils in some areas of the Upper Main region lead to scarce groundwater supplies. In particular, the consecutive dry years (2018, 2019, 2020 and 2022) had a negative impact on the water balance and led to falling groundwater levels, low water levels in streams and crop failures in agriculture. In contrast, the heavy rainfall in June 2024 led to flooding in some regions.

In order to investigate the landscape water balance of the Upper Main area, first a SWAT+ model is setup, calibrated and validated. The model results are then applied to quantify the indicators and evaluate the efficiency of adaptation measures on different WEFE sectors under consideration of climate change.

Furthermore, trade-offs and synergies between the different indicators are identified. The results can be used by decision-makers to develop concrete plans and strategies for sustainable and resilient water management under climate change scenarios.

How to cite: Scherer, N. T., Disse, P. Dr. M., and Huang, Dr. J.: Climate- and socio-economic resilient water governance - a model framework based on WEFE indicators, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20496, https://doi.org/10.5194/egusphere-egu25-20496, 2025.

11:26–12:30