Floods significantly influence land cover such as vegetation in a floodplain. Land cover changes with change in flood characteristics such as frequency, duration, extent, flow depth, and flow velocity. Riparian vegetation type, distribution, and patterns provide habitat for many species. The Geruwa River is a bifurcate of the Karnali River emerging out of the Himalayan foothills in the Terai Arc Landscape. The Geruwa River is part of the Bardiya National Park in western Nepal, which is one of the most important and biodiverse nature reserves in Nepal. Its channel-floodplain system provides, for example, habitat for endangered Gangetic dolphins (Platanista gangetica), bare riverbanks for crocodiles, and riverine grassland-forest mosaics for elephants and tigers. Since the intense monsoon season in 2009, the Geruwa discharge has reduced gradually, initiated by the deposition of coarse sediment over the upstream end of the branch during this monsoon season. The Geruwa branch, which used to be the dominant branch before 2009, now receives only about 20 percent of the Karnali river discharge during the peak flows and about 5 percent during low flows.
Understanding how changing flood characteristics influence the dynamics of floodplain vegetation can help us better manage this important wildlife habitat. Our objective is to quantify the relationship between flood characteristics and vegetation cover in the Geruwa floodplain. We fit a multinomial logistic regression model, where the response is land cover (Forest, Grassland, Agriculture, Bare sediment, and Water) class derived from remote sensing and predictors are flood characteristics derived from hydrodynamic simulations. Model performance is evaluated using spatially stratified cross-validation to reduce bias from spatial autocorrelation. The fitted model will be used to extrapolate vegetation cover under future flood regimes influenced by climate change or anthropogenic activity. To support this analysis, we compiled and constrained flood discharge and duration over the last 63 years. We have developed a two-dimensional flow model to simulate similar floods to derive spatially distributed flood characteristics. We extract vegetation cover over the last 15 years using remote sensing (after channel switch). Preliminary analysis indicates that the decreased flood discharge in Geruwa is followed by an increase in vegetation cover (grassland and forest) in general in the Geruwa floodplain after 2009. Reduced floods in future may increase the succession of grasslands into forests.
How to cite: Gautam, K., Bijlmakers, J., Feng, X., Blom, A., and Bogaard, T.: Relating flood characteristics to vegetation dynamics in the Geruwa floodplain in the Terai Arc Landscape, Nepal, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13149, https://doi.org/10.5194/egusphere-egu26-13149, 2026.
In the western US, intensifying wildfire regimes imply that an increasing fraction of land will exist in a post-fire recovery state at any given time. While much prior work has focused on how forest fires can lead to temporarily suppressed evapotranspiration (ET), few studies have focused on how fire changes the water balance in the shrublands that dominate the arid interior of the western US. There, changes to the water balance are especially important because nearly all precipitation is lost to terrestrial ET, and thus reductions in ET may have especially large effects on streamflow and groundwater recharge. In this presentation, I will show results from a field study in which energy-balance stations in paired post-fire and control plots were used to estimate the relative reduction in ET in the decade following shrubland wildfires; mid-summer ET was often >30% lower in the post-fire plots. I will also show results from a similar analysis at a much greater spatial extent that uses ET values estimated from products developed through NASA’s ECOSTRESS mission; again, these data show reduced ET persisting after wildfires for decades. I will use these findings to discuss the large-scale implications of wildfire on the water balance of the Great Basin region of the western US.
How to cite: Allen, S. T.: Effects of Wildfire on the Water Balance of the Arid Shrublands in the Western United States, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15797, https://doi.org/10.5194/egusphere-egu26-15797, 2026.
Water conservation (WC) is a critical regulating ecosystem service in agropastoral ecotones, yet its spatiotemporal dynamics and driving mechanisms in these vulnerable ecotones remain inadequately understood, hindering sustainable water resource management and ecosystem security. In this study, a novel framework is proposed that coupled the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model with an optimal parameter geodetector (OPGD) to assess the spatiotemporal heterogeneity in WC and its driving mechanism in the Tabu agropastoral ecotone from 2000–2022. Results revealed a pronounced south-to-north decreasing gradient in WC, with an insignificant increase of 0.04 mm/yr. The WC capacities across land use types ranked as follows: high-fractional vegetation cover (FVC) grassland > shrubland > medium-FVC grassland > low-FVC grassland > farmland > bare land > construction land. Hotspots were clustered in the southwest, whereas cold spots were clustered in the north. The areas of the two spots both decreased during 2000–2022, with cold spots disappearing entirely by 2022. Compared with anthropogenic factors (e.g., gross domestic product (GDP), population and the human footprint), natural factors (e.g., precipitation, elevation, temperature and evaporation) had greater influence on WC. Interactions between drivers predominantly exhibited bivariate enhancement, with the interaction between land use and land cover (LULC) and precipitation being the most significant (qi: 0.33–0.67). A dual-pronged spatial strategy considering the optimization of the LULC layout and enhanced interaction is suggested in the ecological planning framework. This research provides critical support for water resource management and the maintenance of ecological security in ecotones. Moreover, it provides a transferable methodological tool for performing ecohydrological evaluations in other regions, particularly in the context of climate change and evolving land use trajectories.
How to cite: Jin, J., Liao, Z., Liu, T., Wang, Z., Wang, M., and Zhang, J.: Integrating an InVEST-OPGD Framework to Decouple the Spatiotemporal Dynamics and Drivers of Water Conservation in the Tabu Agropastoral Ecotone, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2936, https://doi.org/10.5194/egusphere-egu26-2936, 2026.
The Brazilian Cerrado is the largest tropical savanna in South America and contains extensive headwater plateaus that play a central role in aquifer recharge and in sustaining baseflows of regional rivers. With annual precipitation around 1500 mm, a seasonal rainfall regime, and deep tropical soils, water provision under natural vegetation depends strongly on geomorphology, which controls riparian wetlands and favors saturation-excess runoff. The biome exhibits a naturally unfavorable water balance, with high evaporative demand (nearly 70%), a condition aggravated by climate change–driven reductions in drought streamflow. Rapid agricultural expansion further intensifies water stress by reducing infiltration and increasing surface temperatures, highlighting the need for spatially explicit frameworks to guide conservation actions in headwater regions. We analyzed eight medium-sized catchments that are climatically and geologically similar, distributed along a conservation gradient ranging from 16% to 98% native vegetation cover. Based on public data, this quasi-paired dataset allows the hydrological effects of vegetation to be isolated. More preserved catchments exhibited consistently higher drought flows, producing two to four times more water during the dry season, even in years with comparable mean flows. In contrast, agricultural catchments showed faster rainfall responses and lower dry-season runoff coefficients, reflecting limited infiltration and higher evapotranspiration losses. The primary geomorphological descriptor was the Height Above the Nearest Drainage (HAND), used to represent the potential for soil saturation and, complementarily, infiltration. Event-scale analyses of dry-season runoff coefficients revealed a strong dependence of hydrological response on the fraction of the catchment located below specific HAND thresholds. From this calibration, an operational threshold of approximately 11.5 m was identified, consistently discriminating areas prone to saturation from those remaining available for infiltration throughout the year. These empirical results were generalized into a multi-scale decision-support framework. The analysis mapped areas with high natural infiltration potential, concentrated mainly on plateaus associated with highly productive aquifers, such as the Urucuia Aquifer. HAND proved effective in identifying these elevated compartments, where low drainage density and high subsurface storage capacity promote infiltration and baseflow maintenance. Based on this information, a classification of priority areas for water conservation was developed, distinguishing zones where native vegetation preservation is critical from those requiring restoration and soil-management actions. The resulting priority map provides a spatially explicit basis to support land-use and watershed policies in the Cerrado biome.
How to cite: Possantti, I., Barbedo, R., Marques, G., Lira, L., and Salmona, Y.: A geomorphology-based framework for identifying water conservation priorities in the Brazilian Cerrado savanna, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3592, https://doi.org/10.5194/egusphere-egu26-3592, 2026.
The Inner Mongolia Plateau is a significant implementation area of the Three-North Shelter Forest Program in China and a critical zone for climate, hydrology, and ecology. The current pattern of artificial forest and grassland vegetation construction based on precipitation has overlooked the soil water and groundwater carrying capacity. Balancing the effective and sustainable supply capacity of water resources and maintaining the ecological stability of vegetation is a challenge in the governance of desertified and degraded land. This study developed an integrated framework to analyze the spatiotemporal matching degree between vegetation patterns and blue and green water resources, and to evaluate the relationship between vegetation coverage changes and water sources, water balance, and hydrological thresholds. The results show that the green water resource carrying capacity in the Three-North Shelter Forest Program implementation area of the Inner Mongolia Plateau has been underestimated. In contrast, the blue water resource carrying capacity has been overestimated. The water resource demand for forest and grassland vegetation construction is approximately 470 ± 5 million cubic meters, while the available blue water resource is only 178 ± 7 million cubic meters. The areas with increased vegetation coverage are mainly concentrated in basins where blue water resources are declining, and the areas with decreasing groundwater levels are increasing. Increasing vegetation coverage by consuming groundwater for irrigation is not a sustainable path. Under the same precipitation conditions, the spatio-temporal matching degree between vegetation patterns and blue and green water varies significantly. In areas where precipitation is converted into green water resources, vegetation coverage is relatively low, with NDVI values ranging from 0.23 to 0.41; however, the stability of the vegetation ecosystem is relatively strong. In areas where precipitation is converted into blue water resources, the vegetation coverage and its interannual variation trend tend to be stable only when the groundwater depth is between 3 and 12 meters. The research results can provide a scientific basis for ecological restoration and sustainable utilization of water resources in the critical zone of climate-hydrology-ecology.
How to cite: Liao, Z. and Jin, J.: Evaluation of the Spatio-temporal Matching between the Forest and Grassland Vegetation Pattern and Blue-green Water Resources in the Inner Mongolia Plateau, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8448, https://doi.org/10.5194/egusphere-egu26-8448, 2026.
It is increasingly realised that hydrological conditions are not only an abiotic factor for plant communities but also for animals on land including megafauna. Acknowledging the hydrological conditions is of major importance as anthropogenic activities as well as natural processes may change these conditions. Here, we investigate the hydrological conditions and their changes that directly affect terrestrial wildlife in Bardia National Park and the people that live adjacent to this nature reserve. Bardia NP is situated in the flat Terai Arc Landscape at the foot of the Himalayas and hosts the One-Horned Rhinoceros, the Bengal Tiger and the Asian Elephant amongst others.
Bardia NP is bordered in the west by the Geruwa branch of the Karnali River, which is draining the Himalayas in Western Nepal and one of the major tributaries of the Ganges River. Extensive floodplains are associated with the Geruwa branch. High densities of rhinoceros and tigers have been found here thanks to the existing natural water pools as drinking water and cooling facility, dense grassland-forest mosaics providing forage for the rhinoceros and the deer (being prey for the tigers) and also shelter for the tigers. Flow in the Geruwa branch has gradually declined since the intense, double-peaked 2009 Monsoon, which deposited very coarse sediment (boulders) over the Geruwa’s upstream end, contributing to the gradually reducing flow since. The Geruwa branch has been drying up since that time. This has two major implications for wildlife and also human-wildlife conflicts. First, about half of the rhinoceros population has moved to the Indian nature reserve further south in recent years assumed to do so in search for water pools. Second, the Geruwa branch has become a less vivid river for which it is easier for wildlife to cross during wet periods. Strikingly, this area has also been most vulnerable for human – wildlife conflicts in recent years (Paudel et al., 2024, Ecology and Evolution, 2024; 14:e70395).
Another hydrological condition is posed by the artificial water holes at Bardia NP. There are c. 180 artificial water holes around the natore reserve that are essential for drinking water to wildlife. Not all of them are permanent and several rely on groundwater pumping using solar energy. The migration behaviour of the tigers is influenced by their presence as indicated by agent-based modelling of tiger behaviour, and supported by field observations (Thapa et al., Species 2023; 24: e91s1619).
Finally, small irrigation canals are present in the rural area between Bardia NP and the Nepalese – Indian border. It is currently hypothesized that maintenance activities to reduce leakage of these canals have also diminished groundwater recharge. Upon consequence, the groundwater table may have dropped along these canals to depths that are outside the pumping range of hand pumps. These hand pumps are the main drinking water supply for the local communities and the impression is that there is an increasing trend for hand pumps to run dry. This should be further investigated by interviews and hydrological monitoring.
How to cite: Griffioen, J., Gautam, K., Banerjee, I., Bijlmakers, J., Vellekoop, G., Blom, A., Ertsen, M., Bogaard, T., Tumbahangphe, A., Shah, R., and Subedi, N.: Hydrological conditions that directly impact terrestrial wildlife and people in and around Bardia National Park (Nepal), EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8369, https://doi.org/10.5194/egusphere-egu26-8369, 2026.
River and stream networks receive and transport carbon from terrestrial ecosystems to inland waters and ultimately to the oceans, while hosting a suite of biogeochemical processes that result in carbon dioxide (CO2) emissions to the atmosphere. These fluxes are shaped by riverine ecosystem metabolism, defined by the interplay between gross primary production (GPP) and ecosystem respiration (ER). Advances in dissolved oxygen (O2) sensor technology have enabled widespread estimation of daily GPP and ER from high‑frequency O2 dynamics. However, the robust quantification of these metabolic rates remains challenging. In physically dominated, high‑energy environments such as steep channels and step‑riffle systems, continuous gas exchange between the water surface and the atmosphere complicates the estimation of gas transfer velocities and, consequently, metabolism. In addition, GPP is highly sensitive to short‑term variability in light availability, turbidity, and nutrient supply, factors that can fluctuate rapidly in response to hydrological disturbances and land use-land cover change.
Understanding how fluvial metabolism varies across environmental contexts and responds to hydrological and biogeochemical stressors is essential for assessing ecosystem functioning, resilience, and vulnerability. In this study, conducted within the BREATHE Water4All and C-NET projects, we monitored high-frequency O₂ dynamics across three sharply contrasting fluvial environments: (i) a high-mountain glacier-fed stream network, (ii) an agricultural drainage ditch, and (iii) a partially restored urban river. Continuous O2 measurements were combined with ancillary variables, including CO2, water temperature, solar radiation, water level, electrical conductivity, turbidity, nutrients, and colored dissolved organic matter (CDOM). This multi-sensor approach enabled detailed characterization of diel metabolic patterns and identification of the dominant physical and biogeochemical drivers shaping them. The selected case studies span strong gradients in hydrology, geomorphology, nutrient availability, and anthropogenic influence, providing a unique framework to compare site-specific metabolic regimes and ecosystem functioning. Preliminary results indicate marked differences in daily GPP and ER estimates across systems, reflecting the combined effects of nutrient availability, light limitation, hydrologic disturbance, and physically driven gas exchange.
How to cite: Grandi, G., Llanos Paez, O., Hallberg, L., Hou, J., Tolosano, M., Deluigi, N., and Battin, T. I.: Riverine ecosystem metabolism drivers and functioning across environmental and anthropogenic gradients, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16660, https://doi.org/10.5194/egusphere-egu26-16660, 2026.
Lake Urmia has experienced rapid hydrogeochemical transitions and ecological disruption in recent years despite extensive restoration efforts. The Urmia Lake Restoration Program (ULRP) identifies a water level of 1274.1 m a.s.l. as an ecological threshold intended to preserve its keystone species, Artemia urmiana (AU), based solely on empirical relationships linking water level, salinity, and ecological integrity. However, this threshold does not incorporate the mechanistic physiological sensitivities of AU, whose survival, growth, and reproduction respond sharply to changes in habitat salinity. As the lake’s sole grazer of primary producers and a critical food source for migratory birds, AU plays an essential role in sustaining the vulnerable ecosystem of this region. Therefore, a more process-based understanding of how salinity affects AU is necessary to evaluate whether this empirically derived threshold can truly support the species and the broader ecosystem. In this study, we employed a species-specific Dynamic Energy Budget (DEB) model to quantify how increasing salinity affects energy allocation and life-history traits of AU. Then, these physiological outputs were integrated into a population model to evaluate salinity impacts at the population scale. As the salinity of Lake Urmia is locally variable, we combined these results with two-dimensional salinity fields derived from hydrodynamic simulations of the lake to identify suitable areas where AU can thrive. This approach offers a process-based quantitative framework for assessing restoration scenarios and guiding management strategies to avert continued ecological decline and reinforce the resilience and functionality of hypersaline lake ecosystems.
How to cite: Goli, M. and Safaie, A.: Metabolic-Based Assessment of Restoration Strategies in Terminal Hypersaline Lakes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-666, https://doi.org/10.5194/egusphere-egu26-666, 2026.
Consuming freshwater beyond regional carrying capacity—the maximum volume of water that can be sustainably used by human activities—creates ecological water deficits that pose critical threats to aquatic biodiversity and ecosystem integrity. Quantifying the impacts of such deficits is therefore essential for guiding sustainable water use and assessing environmental impacts along global value chains. These impacts are commonly assessed using Life Cycle Impact Assessment (LCIA) frameworks that develop spatially explicit characterization factors for freshwater ecosystems; however, most existing approaches treat water use as an undifferentiated pressure, without distinguishing sustainable freshwater consumption from overconsumption that leads to ecological water deficits. Here, we assess the global impacts of freshwater overconsumption and associated ecological water deficits on freshwater fish species richness using WaterGAP 2.2e data for approximately 11,000 watersheds worldwide. Regional carrying capacity was quantified as available freshwater resources minus environmental water requirements needed to sustain aquatic ecosystems, with ecological water deficits identified where human consumption exceeded this capacity (i.e., freshwater overconsumption). Biodiversity responses were evaluated using a global model linking freshwater fish species richness to river discharge and other covariates (elevation, basin area, and climate zone). Based on this model, two species–discharge relationships (SDRs) were derived to distinguish watersheds experiencing ecological water deficits from those operating within sustainable limits. These SDRs were then used to develop characterization factors quantifying the impacts of human freshwater consumption on freshwater fish biodiversity. Our analysis revealed higher characterization factors in watersheds affected by ecological water deficits, indicating stronger biodiversity impacts under freshwater overconsumption conditions. Explicitly accounting for ecological water deficits in LCIA water-impact assessment can enhance the ecological relevance and accuracy of global characterization factors for freshwater systems and aquatic ecosystems. This, in turn, can support more targeted freshwater management strategies aligned with biodiversity conservation goals.
How to cite: Mtibaa, S., Islam, K., and Motoshita, M.: Assessing the potential impacts of freshwater overconsumption beyond regional carrying capacity on riverine fish species richness, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1922, https://doi.org/10.5194/egusphere-egu26-1922, 2026.
Changes in streamflow regimes and water temperature impact water quality and freshwater biodiversity. Yet the impact of these changes on aquatic biodiversity, especially at fine spatial scale, may vary regionally and often remains unknown. Climate-change impact assessments on freshwater biodiversity are typically done at coarse spatial resolution (>5km), due to a lack of fine scale hydrological information. In this work, we link a hyper resolution global hydrological model (PCR-GLOBWB, 1km) with a species distribution model (SDM). We use this to assess the suitability of current and potential future freshwater habitats for fish species, in the Rhine Basin as a case study. In addition to the high resolution streamflow simulations, we also provide 1km water temperature estimates derived from the DynQual water temperature model.
The results demonstrate that increases in anthropogenic water demands under SSP3 decrease habitat suitability across the entire Rhine basin. We also find that low flows are a higher predictor of freshwater fish suitability compared to water temperatures which is potentially due to the smaller temperature changes in the Rhine basin. Additionally, migratory fish and fish with a larger range of suitable habitats do not see large decreases in their suitabilities due to the larger range of acceptable locations. This work provides the first framework for hyper resolution climate change impact assessments that could be implemented globally and bridges hydrological and biodiversity modelling.
How to cite: Steyaert, J. C., Marquez, J., Domisch, S., Brechbühler, M., Bierkens, M. F. P., and Wanders, N.: High resolution projections of shifts in freshwater biodiversity habitats under global climate change , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19593, https://doi.org/10.5194/egusphere-egu26-19593, 2026.
The south west corner of Australia holds a level of plant diversity unmatched outside tropical rainforests; fostered through millions of years of isolation and relative tectonic and climatic stability. Across deep time, pressures of pollinator scarcity, severe nutrient limitation in an ancient, highly weathered Critical Zone, and fire disturbance have produced what might be the most specialised flora in the world. Southwest Western Australia (SWWA) is also on the bleeding edge of climatic heating and drying, in a trend that has been apparent since the 1960s. Water resources management in response to these trends has made the cities of SWWA global leaders in conservation and water technologies – but as the drying continues, groundwater recharge is dropping, phreatophytic plants are dying, and more severe summer heatwaves and droughts are impacting key ecosystems over huge areas. In this Darcy Oration, I hope to introduce you to the often forgotten, but exceptional set of ecosystems, catchments and Critical Zones of SWWA, and ask how can ecohydrology as a discipline support meaningful adaptation to such climatic changes in this megabiodiverse, hyper-endemic area? I will present a potential hierarchy of actions and research gaps to consider, and suggest that research in support of making decisions about where and how to adapt is a key challenge for our community. Finally, I will spend a little time reflecting on my personal experiences as a caregiver to special needs children, and how those caregiving responsibilities impact a career in hydrological science.
How to cite: Thompson, S.: Ecohydrological Adaptation to Climate Change - from Gondwana to the Globe, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15399, https://doi.org/10.5194/egusphere-egu26-15399, 2026.
Accurately describing forest ecosystem responses to varying climatic conditions—particularly water availability—requires a robust representation of the soil–plant–atmosphere continuum. Recent advances have produced high-fidelity models for both surface–subsurface hydrology and plant hydraulics. Although these model domains partially overlap in the processes they consider, their implementation is often inadequate compared with their counterparts. To address this limitation, we present a coupled version of two established models: the integrated surface–subsurface flow model SERGHEI-SWE-RE and the plant hydraulics model SurEau-Ecos.
SERGHEI-SWE-RE is a performance-portable, high-performance parallel computing model that solves the fully dynamic two-dimensional shallow-water equations for surface flow and the three-dimensional Richards equation for subsurface flow. SurEau-Ecos is a mechanistic, trait-based plant hydraulics model that provides a detailed physiological description of plant water status beyond stomatal closure up to the point of hydraulic failure. The core strengths of both models are coupled through a clean separation at the soil–root interface: SERGHEI-SWE-RE supplies spatially distributed soil water potential fields, while SurEau-Ecos provides the resulting root water uptake. Leveraging the high-performance computing capabilities of SERGHEI-SWE-RE, instances of SurEau-Ecos can be mapped to each node of the surface mesh and the corresponding vertical soil column. This coupled model—spatially distributed and operating at high temporal resolution—captures hydrodynamic processes in complex geometries, such as lateral subsurface flow, exfiltration, ponding, and deep water reserves, while simultaneously enabling the assessment of forest ecosystem responses, such as drought stress and tree dieback.
We present a proof-of-concept version of the coupled model using a transect along an idealised vegetated hillslope, where lateral subsurface fluxes are a key process. The effects of subsurface flow concentration toward the valley on plant-available water are shown and the resulting duration over which trees can sustain drought conditions are analysed.
How to cite: Rickert, G., Martin-StPaul, N., de Cáceres, M., Morales-Hernández, M., Caviedes-Voullième, D., and Özgen-Xian, I.: SERGHEI-SurEau: Coupling surface–subsurface hydrodynamics with plant hydraulics, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14319, https://doi.org/10.5194/egusphere-egu26-14319, 2026.
Terrestrial ecosystem atmosphere exchanges are governed by soil plant hydraulic processes that link soil water availability to transpiration and surface energy fluxes. Physically based soil hydrology models that resolve vertical soil moisture and matric potential gradients using the Richards equation provide the most complete representation of these processes, but their computational cost and parameter demands limit their use in long-term and multi-site applications. As a result, simplified bucket-type soil moisture models remain widely employed despite their coarse treatment of vertical soil water dynamics. Here, we quantify the level of vertical soil hydrologic complexity required for bucket-based models to reproduce the key soil–plant hydraulic behavior of Richards equation models. Using a unified framework, we couple the Penman–Monteith formulation with (i) a single-bucket model, (ii) a hierarchy of multi-bucket configurations with increasing vertical resolution within a fixed soil column, and (iii) a Richards equation model discretized over the same depth. All configurations share a consistent big-leaf canopy representation and explicitly track soil, root, and leaf water potentials and their effects on transpiration and energy fluxes. Model performance is evaluated using soil moisture and latent heat flux observations from diverse AmeriFlux sites spanning grasslands, shrublands, croplands, and forests. We show that similar soil moisture states can produce markedly different transpiration responses due to differences in soil matric potential. The vertical resolution required for bucket models to emulate Richards-based behavior is strongly ecosystem dependent, reflecting contrasts in rooting depth and plant hydraulic strategies. Our results demonstrate that plant-informed, ecosystem-specific soil discretization provides a computationally efficient pathway to improve the representation of soil plant water coupling in land surface models.
How to cite: Sarkar, A. and Dutta, D.: Ecosystem controls on the vertical soil hydrologic complexity required to represent soil-plant-water interactions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10648, https://doi.org/10.5194/egusphere-egu26-10648, 2026.
Shallow subsurface soil water storage is conventionally depicted as a well-mixed reservoir whereby newly fallen precipitation displaces or mixes with existing storage en route to streams—linking transpiration and rootzone storage to streams. Contrary to this core mixing assumption, mounting evidence suggests separations can arise in vadose (unsaturated) zone pore space or flow paths, yet the mechanisms remain poorly constrained. Here, we discuss recent studies from a climate manipulation experiment which use isotopic tracer and numerical techniques to understand the ecohydrological impact of future climactic conditions (elevated atmospheric CO2 and air temperature) on soil water transit and cycling in a temperate grassland. Whereas soil water in this ecosystem typically remained well-mixed, sustained exposure to future climate triggered separations across pore space and between soil horizons—exacerbated by experimental drought. Further, under this future drought scenario the grassland conserved water by restricting evapotranspiration at lower atmospheric water demand than drought exposure in ambient climate. Our results suggest that future climatic conditions may amplify subsurface disconnections in soil water, constraining grassland water use and altering the ecohydrological trajectory of these ecosystems.
How to cite: Radolinski, J., Vremec, M., Kirchner, J., Birk, S., Werner, C., Kahmen, A., Brüggemann, N., Stumpp, C., Nelson, D., Herndl, M., Schaumberge, A., Tissink, M., Wachter, H., and Bahn, M.: A warmer, more CO2-rich climate amplifies hydrological disconnections within soil water, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15292, https://doi.org/10.5194/egusphere-egu26-15292, 2026.
Climate-driven glacier retreat exposes newly ice-free terrain that is progressively colonized by plants, driving ecological succession and altering hydrological and biogeochemical processes in high-mountain ecosystems. Although hydrological impacts of glacier shrinkage have been widely explored, the effects of post-retreat vegetation succession remain poorly quantified. In this study, we apply a mechanistic ecohydrological model (T&C) that explicitly simulates plant migration and species range dynamics to assess hydrological responses to glacier retreat and vegetation succession from 1981 to 2099 under multiple climate change scenarios in a deglaciating ecosystem in the Swiss Alps. The results show that glaciers exert a first-order control on the hydrological cycle, particularly on runoff. Vegetation succession following glacier retreat plays a relatively minor role in hydrological processes initially, but its importance increases over time as glacier cover declines. The combined interactions among glaciers, vegetation and climate significantly modify hydrological regimes, with important implication for projecting future water resources, including changes in terms of magnitude and intra-annual (seasonal) variability, and water quality in high-mountain regions under continued global warming.
How to cite: Jiang, F., Fatichi, S., Paschalis, A., and Peleg, N.: Growing significance of vegetation succession following glacier retreat on high-mountain hydrological cycle , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6665, https://doi.org/10.5194/egusphere-egu26-6665, 2026.
Dust influences plant hydrological functioning in several ways. Dust (or particulate matter) can block or reduce stomatal activity, which regulates gas exchange between the plant and the atmosphere, thereby affecting both transpiration and stomatal conductance. In addition, during dust events, the reduction in solar radiation reaching the plant surface directly influences transpiration rates.
This study aims to examine the effects of dust on plant hydrological responses through systematic monitoring of stomatal conductance and transpiration (using sap flow methods). Two neighbouring plots (east and west) of Citrus (Mandora) trees, located in the Fasouri area (Limassol, Cyprus), were selected for monitoring. In each plot, three representative trees were chosen. Sap flow sensors were installed on each tree, and soil moisture sensors were placed at different depths around the selected trees. Furthermore, weekly measurements of stomatal resistance were taken from six leaves per tree. At the east plot, additional stomatal resistance measurements were obtained from six extra leaves per tree after removing dust from their surface using a microfibre cloth. Meteorological conditions were recorded by a meteorological station within the farm, while particulate matter (PM) data were provided by an air quality station managed by the Department of Labour Inspection of Cyprus. The experiment began in April 2025 and is ongoing.
Preliminary results show similar average stomatal resistance between untreated leaves in the east plot (311 s m⁻¹) and the west plot (303 s m⁻¹). However, treated (dust-free) leaves in the east plot exhibited 19% lower stomatal resistance (255 s m⁻¹) compared to untreated leaves in the same plot, indicating a clear effect of dust on stomatal functioning. Periods during which stomatal resistance was similar between treated and untreated leaves were observed following rainfall events, highlighting the importance of rainfall in maintaining healthy plant hydrological functioning.
How to cite: Eliades, M., Panagiotou, C., Neofytou, E., and Neophytides, S.: Plant Hydrological Responses to Dust: A Case Study from a Citrus Orchard in Cyprus, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9679, https://doi.org/10.5194/egusphere-egu26-9679, 2026.
Quarrying causes extensive degradation of soils, vegetation, and ecosystems, and these effects are further exacerbated by severe weather events and climate change. Consequently, abandoned quarries are some of the most difficult environments to rehabilitate due to the loss of critical ecological functions. Soft engineering solutions, such as vetiver grass (Chrysopogon zizanioides), have been widely used to control erosion, however its potential for water uptake, and application for companion planting in a rehabilitation setting is yet to be explored. Existing literature suggests that vetiver will not only be highly resilient to the harsh environment in abandoned quarries, but it may also improve the hydraulic and microclimatological conditions to aid tree survival and reestablishment. Furthermore, rehabilitation of degraded lands through the extensive root networks of grasses also offers opportunities for enhanced carbon sequestration.
This study aims to determine the ecohydrological potential of vetiver grass to improve the growth rate and survival of forest saplings in abandoned quarries at two study locations. Soil moisture probes were installed at depths of 10, 20, and 40 cm throughout hedgerows with and without vetiver of varying ages. Soil temperature, air temperature, relative humidity, and rainfall were recorded, and plant, soil, stream, and rainfall samples were collected for stable isotope analysis. Results show that show that vetiver significantly influenced soil moisture, and vapor pressure deficit (VPD) with effects varying by season and site (p <0.05; a = 0.05). While there was some improvement in soil chemical and physical properties within the shallow rooting zone (p <0.05; a = 0.05), there was no improvement to sapling survival at either site. Stable water isotope analyses show that saplings and Vetiver relied on the same shallow 0–20 cm water sources, indicating competition likely driven by limited rooting depth. Nonetheless, if integrated thoughtfully, vetiver can support biodiversity and increase rooting complexity, improving water and nutrient cycling.
These findings highlight vetiver’s capacity to modify microclimatic and shallow soil conditions but also reveal some constraints for its use as a companion species in early forest restoration. Future work should examine soil amendments or pre-rehabilitation treatments to enhance rooting depth and reduce competition before implementing vetiver-based interventions.
How to cite: Farrick, K. and Lee, V.: The ecohydrological potential of Vetiver Grass (Chrysopogon zizanioides) for Forest Rehabilitation in abandoned quarries, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14854, https://doi.org/10.5194/egusphere-egu26-14854, 2026.
Adaptation of ecosystems’ root zones to climate change critically affects drought resilience and vegetation productivity. However, a global quantitative assessment of this mechanism is missing. In this study, we applied the mass curve technique (MCT) based on water balance to estimate the global root zone water storage capacity (SR) using high-quality observation-based data. Our results show that the global average SR increased by 11%, from 182 to 202 mm in 1982–2020. The total increase of SR equals to 1652 billion m3 over the past four decades. SR increased in 9 out of 12 land cover types, while three relatively dry types experienced decreasing trends, potentially suggesting the crossing of ecosystems’ tipping points. Our results underscore the importance of accounting for root zone dynamics under climate change to assess drought impacts.
How to cite: Xi, Q. and Gao, H.: Terrestrial ecosystems enhanced root zone water storage capacity in response to climate change over the past four decades, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2124, https://doi.org/10.5194/egusphere-egu26-2124, 2026.
This study aims to understand water uptake depths and dynamics of tropical dry forest trees, namely RonRon (Astronium graveolens), Guacimo (Guazuma ulmifolia), Guapinol (Hymenaea courbaril) and Caoba (Swietenia macrophylla), at Estación Experimental Forestal Horizontes, an intensively monitored research site in northwestern Costa Rica. The climate of this region is driven by the El Niño–Southern Oscillation, which results in distinct wet (June to December) and dry seasons (December to May). We combine field measurements of sap flow and soil moisture, collected between December 2020 to December 2021, to estimate plant hydraulic traits through inverse modelling with a differential evolution approach using the mechanistic plant hydraulic model SurEau-Ecos. This allowed the estimate of 12 plant hydraulic parameters for each of these four species. We compare these inversely estimated traits across species and link them to observed soil moisture and sap flow dynamics. Our results show distinct hydraulic strategies for each plant, which feedback into the spatiotemporal dynamics of soil moisture. Caoba and Guacimo conserve water through early stomatal closure to inhibit transpiration during the dry season, while RonRon and Guapinol keep their stomata open and sustain a relatively higher transpiration rate even with limited soil moisture. Overall, clear differences in drought-response strategies among species, including general isohydric and anisohydric behavior, are shown both in estimated plant hydraulic traits and in ecohydrological signatures. A limitation of this study is that interspecies interactions have been neglected. Nevertheless, fair agreement between model results and field observations has been achieved. Our findings contribute to the mechanistic understanding of hydraulic strategies of tropical dry forests, which are currently understudied ecosystems.
How to cite: Shokrollahi, M., Rickert, G., Iden, S., Beyer, M., Iraheta, A., Martin-StPaul, N., Klaus, J., and Özgen-Xian, I.: Inverse modelling to estimate plant hydraulic traits and water use strategies in a Costa Rican tropical dry forest, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5062, https://doi.org/10.5194/egusphere-egu26-5062, 2026.
Białka River Valley (Natura 2000 site, PLH120024) is one of the most important natural areas in the Polish part of the Carpathians. It serves as a key ecological corridor and provides important habitats for many animal species. The primary objective of this area is the protection of the river’s natural character. During field surveys conducted in 2023, almost 300 waste dumping sites were mapped within an area of 716 hectares. Dominant type of waste was plastic (mainly plastic bags – 46% and PET bottles – 45.7%). Other identified waste fractions included construction waste (26.3%), metal (24.7%) and glass (22.3%). With regard to dump size, 21.7% of the sites were classified as large (e.g. equivalent to a dump truck load of waste, while 22.7% were classified as medium (e.g. equivalent to a wheelbarrow load). The presence of environmentally hazardous waste (such as batteries, accumulators, grease, oils) was also mapped. This may affect the ionic composition of the water, increasing conductivity and creating a real threat to the environment (including water pollution or fire). Additionally, waste materials may be transported downstream by river flow, exposing other places to environmental hazards. A total of 63% of all dumping sites were visually exposed, which negatively affects the landscape in mountainous regions. The dominant land-cover types within the study area were forest (35.7%), grasslands (33.3%) and shrubs (24%). Approximately 32% of the identified waste consisted of recyclable materials, which could be effectively eliminated under appropriate waste management practices. In 2026, repeat field mapping will be carried out to enable comparative analysis and to assess changes from ecological, hydrological perspectives.
How to cite: Suwalska, W., Kaflińska, O., Jakiel, M., Kurzac, M., Staniek, J., Świerczek, K., Zaremba, W., Ziarnik, A., and Żelazny, M.: Problem of the illegal dumping sitesin the Białka Valley, Carpathian Mountains, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8256, https://doi.org/10.5194/egusphere-egu26-8256, 2026.
Fishways are structures built across dams to restore river connectivity and allow fish to pass through. Their effectiveness depends strongly on fish swimming behaviour and interaction with the flow hydrodynamics within the fishway. However, most fish-passage efficiency is still measured by counting the number of fish that successfully pass the structure. This metric alone does not capture the behavioural difficulty or the energetic cost experienced by individual fish. Therefore, in this study, we investigated the effort required for fish to pass a multi-slot fishway (MSF) using fish-tracking experiments. Ten Labeo rohita (rohu) were tested in a multi-slot fishway operated at two discharges (15 and 25 L/s). Individual fish trajectories were used to quantify passage success, the number of attempts, and swimming speed. Passage efficiency was similar at both discharges; however, the effort required to pass through the fishway differed. Fish at 15 L/s made more repeated approaches before passing, whereas fish at 25 L/s typically passed in fewer attempts. To quantify energetic cost, we calculated an effort index based on the swimming speed, representing the mechanical power used during passage. This index was higher at 15 L/s, indicating greater energy use due to repeated searching and failed approaches. Fish trajectory showed that fish at lower discharge spent more time in low-velocity and recirculating flow regions, while higher discharge produced a clearer attraction flow that guided fish directly to the slot. This study introduces a behavioural and energetic metric that complements traditional passage efficiency and provides a more informative measure of fishway performance. These results suggest an important role for hydraulic conditions in promoting guidance and movement, and highlight the importance of including behavioural and energetic considerations when evaluating passage performance.
Keywords: Fish passage, Fish behaviour, multi-slot fishway, swimming energetics, river connectivity
How to cite: Daksh, K., Malasani, G. C., Chandra, V., and Theodore, C.-S.: Energetic and behavioural metrics for evaluating multi-slot fishway performance, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8809, https://doi.org/10.5194/egusphere-egu26-8809, 2026.
Throughfall represents the primary pathway by which rainfall reaches the ground beneath any vegetation canopies through free throughfall (FR), splash throughfall (SP), and canopy drip (CD). This partitioning of throughfall fundamentally influences subsurface hydrological processes, particularly soil moisture responses under trees. This study examines the contributions of FR, SP, and CD to soil moisture responses under the birch (Betula pendula Roth.) and pine (Pinus nigra Arnold) trees. To quantify the relative proportions of FR, SP, and CD under each tree, simultaneous drop size data of gross rainfall and throughfall were measured using an OTT Parsivel disdrometer. The volumetric soil water content (VWC) under both trees was monitored using TEROS 10 sensors installed at three different depth profiles (16–20, 51–54, 74–76 cm). Findings demonstrate that a higher fraction of FR delivers unimpeded, rapid water inputs below the birch, which elicit faster upper soil moisture responses. Whereas, CD dominates throughfall volume under the pine, which provides a more gradual delivery of water inputs, resulting in a more delayed soil moisture response compared to birch. Statistical analysis further reveals a significant positive trend in Spearman correlation coefficients between throughfall types and lagged soil moisture at 16 cm depth under both trees. Correlations of SP and FR with soil moisture were consistently higher under the birch than the pine, suggesting more direct and rapid responses of VWC to these components beneath the birch. Under the pine, responses were more delayed, reflecting lower FR frequency due to higher interception and CD dominance in throughfall delivery. This implies the slower release of water from pine's needle-like foliage, resulting in a prolonged moisture response. Event-based analysis also shows that the increase in VWC under the birch corresponds more closely with periods of increased FR contribution. Although SP contributes to overall throughfall, the more direct, less diffuse nature of FR may be more effective in delivering water to the soil surface, triggering rapid soil moisture responses at 16 cm. Conversely, the VWC under the pine doesn't strongly correspond with peaks in FR or SP alone. Instead, gradual VWC increases at 16 cm correspond to sustained CD, punctuated by minor increments during concurrent FR and SP inputs. These findings elucidate how the different components of throughfall differentially drive event‑scale soil moisture responses beneath tree canopies, thus improving the understanding of small‑scale pathways by which canopy rainfall redistribution governs infiltration, storage, and percolation.
Acknowledgment: This work was supported by the P2-0180 research program through the Ph.D. grant to the first author, which is financially supported by the Slovenian Research and Innovation Agency (ARIS). Moreover, this study was also carried out within the scope of the ongoing research projects J6-4628, J2-4489, and N2-0313 supported by the ARIS and SpongeScapes project (Grant Agreement ID No. 101112738), which is supported by the European Union’s Horizon Europe research and innovation programme.
How to cite: Alivio, M. B., Šraj, M., and Bezak, N.: Contributions of different throughfall types to the soil moisture responses under the trees, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8839, https://doi.org/10.5194/egusphere-egu26-8839, 2026.
Comprehensive in-situ hydrological measurements in tropical environments face significant data challenges. Multi-sensor deployments often result in incomplete temporal coverage due to installations in phases, sensor malfunctions, and maintenance requirements. These data gaps, combined with sensor-specific calibration uncertainties and measurement noise, introduce substantial uncertainties that are rarely quantified, particularly in the tropics where such datasets are scarce.
Data quality control and uncertainty quantification become critical when integrating measurements from diverse sensor types that measure different areas and have different types of errors. Raw sensor data require cleaning protocols to identify and address outliers and systematic biases. Furthermore, translating single-point measurements into catchment-scale estimates introduces scaling challenges that add to the existing uncertainties of each sensor.
This study looks at these challenges using data from 2022–2025 in the Kent Ridge experimental catchment in Singapore characterized by different land types (grass, forest, built-up areas). Our integrated sensor network combines pressure transducers for surface water level (used to derive flow rates) and groundwater table monitoring, drainage lysimeters, plant physiological sensors (sap flow meters, dendrometers, leaf wetness sensors), multi-depth soil moisture monitoring, soil temperature sensors, PAR sensors (Photosynthetically Active Radiation), and weather data including rainfall, wind speed and direction, air temperature, vapor pressure deficit, and solar radiation.
We apply data cleaning procedures and employ different uncertainty quantification methods to interpret sensor-specific outputs and evaluate how data gaps affect the overall measurement uncertainty. Results quantify typical measurement errors in urban tropical catchment and demonstrate practical approaches for handling imperfect multi-sensor datasets in real world environments.
How to cite: Bironne, A., Drillet, Z., Chaput, A., Floriancic, M., Ivanov, V. Y., Ooi, S. K., Babovic, V., and Fatichi, S.: Multi-Sensor Assessment and Uncertainty Quantification of Integrated Hydrological Components in a Tropical Experimental Catchment., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9193, https://doi.org/10.5194/egusphere-egu26-9193, 2026.
Highly urbanised areas are tough environments for trees, often compared to arid lands. Drought stress detection and prediction in urban trees is of utmost importance for the sustainable management of the urban forest. The high heterogeneity of the urban fabric presents a major challenge for identifying the hierarchy of controls on tree drought stress. In this contribution, we combine field observations of soil moisture and sap flow measurements with mechanistic plant hydraulic modelling to disentangle this hierarchy in the city of Braunschweig, Germany. We use a modified version of the plant hydraulic model SurEau-Ecos for inverse hydraulic trait estimation of different tree species at sites spanning a gradient of surface sealing. The investigated species are cypress oak (Quercus robur 'Fastigiata'), Turkish hazel (Corylus colurna), and littleleaf linden (Tilia cordata). Anthropogenic structures such as drainage pipes and other elements of the urban karst significantly affect both soil and plant water dynamics, driving high intra-species trait variation across sites. This suggests co-adaptation of tree hydraulic traits and micro-environmental conditions at the patch scale. Our results indicate that intra-species hydraulic trait plasticity and soil moisture availability are the main factors controlling drought stress in urban trees.
How to cite: Özgen-Xian, I., Hörmann, V., Shokrollahi, M., Rickert, G., Gerchow, M., Beyer, M., Iden, S., Martin-StPaul, N., and Strohbach, M.: Disentangling controls on drought stress in urban trees in a Central European city, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10377, https://doi.org/10.5194/egusphere-egu26-10377, 2026.
European beech (Fagus sylvatica) is among the most ecologically and economically important tree species in Europe. Climate change impacts on beech forests are already measurable in large parts of its distribution range, with climate-driven growth decline expected across large areas in the near future. Many regions are anticipated to shift from energy- to water- limited functioning, altering in turn forest ecosystem functions. However, previous studies have mostly focused on dendrochronological analyses, while the behavior of beech forests under climate change must be understood as a coupled carbon-water problem, requiring integrated ecosystem scale approaches. This study aims to provide process-based understanding of how and to what extent the carbon and water cycles in beech forests will be affected in the coming decades, analyzing the impact of climate and atmospheric CO2 on the carbon use efficiency CUE, i.e. the ratio between net and gross primary productivity, and water use efficiency WUE, i.e. the ratio between gross primary productivity and evapotranspiration, as key-indicators of the ecosystem functioning. Therefore, we used a mechanistic, state-of-the-art forest ecosystem model, namely 3D-CMCC-FEM, to simulate carbon and water cycles in ~500 beech stands located across the Italian territory, from the pre-alpine zone to the southernmost region. The sites span thus broad latitudinal and altitudinal gradients, capturing diverse climatic conditions. Additionally, the selected forest stands show different structural characteristics resulting from varying site histories and legacy effects.
Model simulations are carried under current climate conditions and three climate change scenarios from downscaled CMIP6 climate projections, covering the years 2005-2100. Structural data to initialize the model in 2005 are built on measurement of key structural variables from the second Italian Forest Inventory. Taking advantage of in situ measurements and remote-sensing based observations, we evaluate and constrain the ecosystem model processes. We finally analyze how CUE and WUE trajectories covary across the climate space under different climate scenarios taking in to account the role of forest structure, aiming at identifying potential carbon-water trade-offs as forests face changing climatic conditions.
How to cite: Dalmonech, D., Massari, C., Anav, A., Vangi, E., Avanzi, F., and Collalti, A.: “From energy to water limitation: projecting carbon and water cycling in mediterranean beech forests under climate change”, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11700, https://doi.org/10.5194/egusphere-egu26-11700, 2026.
Modernizing hydropower is increasingly recognized as a key strategy for restoring the biodiversity of rivers. However, factors beyond ecological benefits often influence decisions regarding hydropower operations and management. Historically, the needs of local populations and environmental considerations have not been prioritized. Modernising hydropower is inherently transdisciplinary, requiring a balance of multiple objectives. In RE-HYDRO project, we developed an integrated framework to address these complex challenges for case studies in Finland and Sweden. This work involves not only hydrological and hydraulic modelling of regulated rivers but also a) assessing the faunistic biodiversity in the riparian zones affected by hydropower and b) examining the effects of hydropower on local identity and the cultural environment. This comprehensive approach would allow us to evaluate the biodiversity dynamics and explore the potential for habitat restoration in these regulated rivers while updating the hydropower management with climate change.
How to cite: Patro, E. R., Ahonen, J., Kaggwa Nakigudde, C., Cunico, M., Andreasson, P., Hellström, G., Andersson, A., Soikkeli, A., Haghighi, A. T., and Singh, N. J.: Hydropower 2.0 Powering green transition in a more sustainable way: Project RE-HYDRO, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16978, https://doi.org/10.5194/egusphere-egu26-16978, 2026.
Glacier retreat driven by climate change is expected to alter hydrological and chemical conditions in glacier-fed streams, with consequences for macroinvertebrate community structure and function. To assess long-term community responses to changing runoff regimes, we revisited the glacier-fed Vestari-Jökulsá River in Iceland, originally studied in 1996/97, and compared historical data with new measurements collected in 2022.
Macroinvertebrate species richness, Shannon diversity, and evenness declined at several sites, while total organism density remained relatively stable. Analyses of community composition based on Bray-Curtis dissimilarities revealed higher similarity among sites in 2022 compared to 1996/97, suggesting increasing homogenization of assemblages with glacial retreat. As runoff regime has been identified as a key driver of future community change, we examine hydrological dynamics in the catchment in relation to observed ecological changes and predicted runoff scenarios. Ongoing analyses focus on trends in annual discharge and seasonal dynamics, including the timing of melt onset and potential changes in winter and summer runoff.
By integrating long-term ecological, hydrological, and chemical perspectives, this study enhances understanding of climate-driven changes in glacier-fed stream ecosystems.
How to cite: Knauft, A. M., Gíslason, G. M., Reiss, M., Ólafsson, J. S., Hansen, I., Magnúsdóttir, R. Þ., and Chifflard, P.: Linking river discharge and macroinvertebrate communities under climate change in a glacier-fed stream, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20691, https://doi.org/10.5194/egusphere-egu26-20691, 2026.
Despite the growing recognition that ecohydrological processes underpin water-related ecosystem services, conceptual integration between ecology, hydrology, and landscape ecology remains fragmented. The study analyzed 1,855 articles published between 1974 and 2020 in Scopus, using co-occurrence networks, thematic evolution mapping, and multiple correspondence analysis to uncover knowledge gaps and disciplinary boundaries in ecohydrology. Results revealed that while publications grew at 12.16% annually—with marked increases following UNESCO's formalization of ecohydrology (1995) and the adoption of the SDGs (2015)—conceptual distance persists between "ecosystem services" and specific hydrological variables. Surface runoff was consistently linked to land-use changes, while evapotranspiration, a major component of the hydrological cycle, was underrepresented.
To address these gaps, a multiscale ecohydrological conceptual model is proposed, positioning evapotranspiration as a central integrating variable connecting ecosystem structure with water service provision. The model identifies four structural control variables—leaf area index, root depth, canopy structure, and soil properties—as modifiable attributes influencing the biophysical limits within which ecohydrological processes operate. The model also acknowledges scale dependence: microscale processes are influenced by species-soil-water interactions, mesoscale dynamics are determined by hydrological connectivity, and macroscale responses involve atmospheric moisture recycling. This framework complements integrated water resource management by incorporating ecohydrological variables as ecosystem service indicators, highlighting nonlinear thresholds of change, and emphasizing feedbacks between anthropogenic landscape modifications and hydrological cycle alterations.
How to cite: Zamora, D. and Donado, L. D.: An Integrative Ecohydrological Framework Linking Variables and Water Ecosystem Services Derived from Bibliometric Analysis, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21853, https://doi.org/10.5194/egusphere-egu26-21853, 2026.
