Response of water resources in Jialing River Basin to environmental changes using a remote sensing enhanced hydrological model

Study region Jialing River Basin of southwest China. Study focus Climate change exacerbates the imbalance in water-resource allocation, while land-surface conditions strongly regulate water resources across different spatial and temporal scales . In this study, the spatiotemporal characteristics of blue and green water resources (BW and GW) were evaluated based on the Soil and Water Assessment Tool (SWAT), and the impacts of climate change (CC) and land-surface change (LSC) on blue-green water resources in the basin were investigated. New hydrological insights for the region First, from 2000 to 2020, both BW and GW showed an increasing trend with 3.61 mm/year and 4.63 mm/year, respectively. The spatial distribution of BW and GW changes is uneven. Second, CC drives the variations in blue-green water within the basin. LSC can locally reverse the dominant influence of climate change. Third, CC not only directly influences the spatiotemporal characteristics of blue-green water, but also alters their dynamic partitioning by modifying the land-surface conditions, notably through vegetation greening. Our results highlight that CC impacts water resources not only directly, but also indirectly by altering vegetation. This implies that water management policies account for these complex climate-vegetation-water feedbacks to ensure sustainability and resilience in the upper Yangtze River.