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The Yellow River Basin faces water scarcity and ecological fragility. Changes on the land surface, characterized by large‐scale soil and water conservation measures, have a significant impact on river runoff and ecological environment. However, there are still great uncertainties in the scientific understanding of the mechanisms by which multiple driver impact eco‐hydrological processes due to the diversity of land surfaces and the complexity of the coupling processes. As an international scientific frontier on interdisciplinary studies in climatology, hydrology, ecology, and other related fields, it is significant to study the mechanisms and assess the impacts of land surface change on eco‐hydrological risk to support ecological restoration plan and sustainable water resources utilization in the Yellow River Basin. Taking the Yellow River Basin as the study area, this study proposes several important research initiatives, focusing on addressing the ecological and water resources problems in the Loess Plateau. These initiatives include (1) to quantify the individual effect of land surface elements (e.g., vegetation, terraces, and check dam) and reveal the nonlinear driving mechanisms of multiple drivers on eco‐hydrological processes; (2) to construct a distributed eco‐hydrological model that couples dynamic land surface features, and simulate eco‐hydrological processes in a changing environment; (3) to improve the ecological risk assessment indicator system and methods for assessing the impacts of land surface changes on eco‐hydrological synergistic functions and ecological risk; (4) to establish an ecological regulation model based on multiobjective game theory and adopt an adaptive regulation mode for ecological risk management. The research could enrich the scientific understanding and theory of eco‐hydrology, and prompt disciplinary studies of ecology, hydrology, climatology, and other fields. The expected academic achievements will innovate eco‐hydrological simulation and assessment techniques in a changing environment, and strongly support the implementation of the national strategy for ecological protection and high‐quality development in the Yellow River Basin.

Accurate quantification of ecohydrological processes is essential for effective water and carbon management in terrestrial ecosystems. Traditional simulations mainly rely on mechanistic models, yet their accuracy is often limited by inconsistencies in representing physical processes and uncertainties in parameterization. Integrating remote sensing signals offers a promising way to reduce these uncertainties and enhance model applicability. In this study, in-situ observations from a wheat cropland in the Guanzhong Plain were used to simulate gross primary productivity (GPP) and latent heat flux (LE) by comparing a forward model (STEMMUS-SCOPE) with a remote sensing-driven inverse model (STEMMUS-MLR). We further examined the role of solar-induced chlorophyll fluorescence (SIF), an emerging proxy for photosynthesis, as an input to improve mechanistic modeling of GPP and LE. Results show that STEMMUS-MLR outperformed STEMMUS-SCOPE in estimating water and carbon fluxes, demonstrating that incorporating SIF effectively reduces bias associated with uncertainties in parameters and forcing data. The contribution of SIF was quantified using Random Forest regression and Shapley additive explanations (SHAP), revealing that SIF markedly reduced the dependence of GPP and LE simulations on shortwave radiation (SW), air temperature (Ta), and leaf area index (LAI). These findings highlight the critical role of SIF in ecohydrological modeling of semi-arid cropland ecosystems and provide a scientific basis for advancing process understanding and improving the precision management of water and carbon budgets in terrestrial ecosystems.

Water temperature (Tw) plays a critical role in the aquatic ecosystem of rivers. Studying the response process and mechanisms of Tw to climate change and human activities is crucial for assessing the sustainable development of river ecological environments. In this study, we conducted a multi-time scale analysis of Tw using mathematical and statistical models and a vector autoregressive model. We analyzed hydrometeorological data collected from 1961 to 2019 to understand the evolutionary characteristics of Tw under different meteorological conditions and reservoir operation stages. Our findings reveal a significant mutation in Tw in 1994, with the warming rate changing from 0.007 to 0.032 °C/year. Among the various meteorological factors examined [runoff, evapotranspiration, air temperature (Ta), rainfall, duration of sunshine, wind speed, air pressure, and solar radiation], Ta and runoff were found to have the greatest influence on Tw, accounting for > 30% of the observed changes. Conversely, the wind speed had the weakest impact. Furthermore, the Three Gorges Dam (TGD) exerted a substantial influence on Tw. The presence of the TGD elevated winter Tw compared to the non-impoundment condition. Additionally, the completion of the TGD significantly weakened the correlation between runoff, Ta, and Tw, resulting in a 25–34 day delay in the Chinese sturgeon's target spawning time. This delay could have negative ecological implications for the lower reaches of the TGD. These findings offer essential support for guiding water resource management, protecting river eco-hydrological processes, and understanding the impact on aquatic ecology in the Yangtze River.

ABSTRACT The greater probability of small rainfall events occurring in semi-arid regions, and the little understanding of their role in hydrological processes, has led to this investigation of surface runoff generated during these events in two adjacent micro basins in the Brazilian semi-arid region. The types of plant cover to be investigated were the Phytogeographical Caatinga Domain under regeneration for 35 years (CPDReg) and thinned CPD (CPDThin), which consisted of the elimination of trees with a diameter of <10 cm. Two historical series were considered, one of 40 years (1974-2013) with 2,259 events and the other consisting of 247 rainfall events of <30 mm from 2009 to 2013. The cumulative frequency distribution showed that the series of 247 24-hour events proved to be statistically representative in investigating hydrological processes in the Brazilian semi-arid region, compared to the long series of 2,259 events. Irrespective of the pattern, rainfall with an intensity of less than 17 mm h-1 generated effective precipitation with small depths (<2 mm). Regardless of the rainfall pattern, the lowest effective precipitation was registered for the plant cover of thinned CPD, both on an annual scale and per event. The occurrence of 3 or 4 consecutive dry days is enough for events of <30 mm to generate no runoff, due to the appearance of micro-cracks formed in vertisols during the drying process. It is believed, therefore, that the expansion and contraction of vertic soils is the main determinant for the start of Pe in areas with a water source (micro basins of <2 ha) in the CPD.

Understanding complex urban eco-hydrological processes through models is an important approach in sponge city construction. However, the research on this has not kept pace with the urgent need for sustainable development of urban water resources, which makes the current construction efficiencies unsatisfactory. This review highlights the importance of establishing a multi-scale urban distributed eco-hydrological model by analyzing the connotations of sponge city construction. Hydrological models that can be configured for sponge city construction were selected. Traditional models have limitations in coupling ecological and hydrological processes, multi-scale and landscape-based simulations, refined simulations, and computational efficiency. By contrast, cellular automaton has a discrete data structure in space, time, and states, is capable of bottom-up computing, and provides a new conceptual framework for simulating complex urban eco-hydrological processes. Future model development may focus on the conduction of multi-scale simulation systems, the simulation of coupled urban eco-hydrological processes, the quantification of eco-hydrological responses to land cover composition, spatial configuration and low impact development practices, and improving simulation accuracy.

Increased nitrogen (N) concentrations in water bodies have highlighted issues regarding nutrient pollution in agricultural catchments. In this study, the ammonium-N (NH 4 + -N), nitrate-N (NO 3 − -N), and total N (TN) concentrations were observed in the stream water and groundwater of two contrasting catchments (named Tuojia and Jianshan) in subtropical central China from 2010 to 2014, to determine the rice agriculture impacts on the hydrographic patterns, and N export characteristics of the catchments. The results suggested that greater amounts of stream flow (523.0 vs. 434.7 mm year −1 ) and base flow (237.6 vs. 142.8 mm year −1 ) were produced in Tuojia than in Jianshan, and a greater base flow contribution to stream flow and higher frequencies of high-base flow days were observed during the fallow season than during the rice-growing season, indicating that intensive rice agriculture strongly influences the catchment hydrographic pattern. Rice agriculture resulted in moderate N pollution in the stream water and groundwater, particularly in Tuojia. Primarily, rice agriculture increased the NH 4 + -N concentration in the stream water; however, it increased the NO 3 − -N concentrations in the groundwater, suggesting that the different N species in the paddy fields migrated out of the catchments through distinct hydrological pathways. The average TN loading via stream flow and base flow was greater in Tuojia than in Jianshan (1.72 and 0.58 vs. 0.72 and 0.15 kg N ha −1  month −1 , respectively). Greater TN loading via stream flow was observed during the fallow season in Tuojia and during the rice-growing season in Jianshan, and these different results were most likely a result of the higher base flow contribution to TN loading (33.5 vs. 21.3%) and greater base flow enrichment ratio (1.062 vs. 0.876) in Tuojia than in Jianshan. Therefore, the impact of rice agriculture on catchment eco-hydrological processes should be considered when performing water quality protection and treatment in subtropical central China.

TOPOG model is an eco-hydrological model designed during forest hydrological studies with small watersheds in tropical region. In order to test the applicability of TOPOG for simulating the hydrological effects of forests in small watersheds of temperate zone, the meausered eco-and hydrological data in the growing seasons of 2001 and 2002 in the small watershed of Pailugou in Qilian Mountains were selected to simulate the hydrological processes such as canopy interception, evapotranspiration of different vegetation types and watershed runoff by using the \"yield\" mode of TOPOG. It showed that the canopy interception simulated matches the measured well when the rainfall amount of single rainfall events varies within 5 similar to 25 mm, and the total evapotranspiration as well as their composition from the forest stands of Picea crassifolia which grow within the elevation range of 2 730 similar to 3 100 m could be more accurately simulated; for the grasslands growing within the elevation range of 2 700 similar t

Forest roads are a common land use feature with a significant impact on sediment yield and the water sediment transport processes within a watershed, seriously disrupting the safety and stability of the watershed. Previous studies have focused on the sediment production processes within the road prism. However, there has been limited attention given to the transport processes of road-eroded sediment at various scales, which is crucial for understanding the off-site effects of road erosion. This paper reviews research conducted on forest road erosion over the past two decades. It summarizes the mechanisms of sediment production from road erosion and provides a detailed analysis of the transport mechanisms of eroded sediments from roads to streams at the watershed scale. The paper also examines the ecological and hydrological effects, research methods, and control measures related to sediment transport caused by forest road erosion. It identifies current research limitations and outlines future research directions. The findings of this review highlight several key points: (1) Most research on forest road erosion tends to be specific and unilateral, often neglecting the broader interaction between roads and the watershed in terms of water–sediment dynamics. (2) Various research methods are employed in the study of forest road erosion, including field monitoring, artificial simulation experiments, and road erosion prediction models. Each method has its advantages and disadvantages, but the integration of emerging technologies like laser scanning and fingerprint recognition remains underutilized, hindering the simultaneous achievement of convenience and accuracy. (3) The transport processes of forest road-eroded sediment, particularly on road–stream slopes, are influenced by numerous factors, including terrain, soil, and vegetation. These processes exhibit significant spatial and temporal variability, and the precise quantification of sediment transport efficiency to the stream remains challenging due to a lack of long-term and stable investigation and monitoring methods. The establishment and operation of runoff plots and sedimentation basins may help offer a solution to this challenge. (4) Both biological and engineering measures have proven effective in reducing and limiting sediment erosion and transport. However, the costs and economic benefits associated with these regulation measures require further investigation. This review provides a comprehensive summary of relevant research on sediment erosion and transport processes on unpaved forest roads, enhancing our understanding of sediment yield in watersheds and offering valuable insights for reducing sediment production and transport to streams.