Modelling water yield services in the Shule River Basin under multiple scenarios of climate and land use change

The Shule River Basin is a typical inland river basin in arid areas， and its water yield is crucial for regional ecological security and sustainable development. This study integrated the FLUS and InVEST models to simulate the basin's water yield in 2030 and 2050 under three climate scenarios （SSP119， SSP245， and SSP585）. Geographical detectors were further applied to quantify the driving mechanisms of natural and human factors. The key findings are as follows： 1） Land use in the basin is dominated by desert. Under the SSP119 scenario， the desert area is projected to decrease by 0.69% by 2050， whereas it is projected to increase sharply by 5.7% under the SSP585 scenario. 2） The spatial distribution of water yield exhibits a pattern of higher values in the south and lower values in the north， with high-yield areas concentrated in glacier-covered areas and high-altitude mountainous regions. The most significant increase in water yield occurs under the SSP119 scenario， while the SSP585 scenario shows only a minimal increase due to extreme climate conditions. 3） Precipitation and DEM are identified as the core driving factors governing the spatial distribution of water yield. The interaction between land-use type and precipitation has the strongest influence， indicating that artificial changes in land use can significantly regulate water yield. This research provides a multi-scenario framework to guide water resource management and ecological governance for inland river basins of arid areas.