基于Budyko方程的我国各大流域1900-2100年水资源量演变规律OA

Understanding historical and future water resources dynamics is essential for sustainable basin management.Using the Budyko equation and CMIP6 multi-model data,a total differential approach was applied to quantify the contributions of precipitation and potential evapotranspiration to water resource dynamics across China's major river basins.Historical observations indicate that water resources declined in over 40%of the country,with an 80%confidence interval of-4.13 to-2.01 mm/a.Under the SSP126,SSP370,and SSP585 scenarios,water resources show overall increases but with significant spatiotemporal variability and uncertainty.For river basins in Southwest China,the projected variation ranges are-11.16%to 20.49%,-14.70%to 28.62%,and-10.89%to 46.43%,respectively.Attribution analysis across nine representative basins reveals that reduced precipitation and increased potential evapotranspiration jointly drive water resource declines in more than 60%of years,with dominant drivers varying by basin and scenario.The relative contribution of decreasing precipitation gradually increases with rising aridity index.Reduced precipitation remains the dominant factor in arid regions,with contribution on rates of 0.93 for the historical period and 0.65,0.60,and 0.60 for the three future emission scenarios,respectively.This study provides a scientific basis for the long-term optimal allocation of water resources in China's major river basins.