岩溶区径流与水文干旱预估——以赤水河上游流域为例OA

In this study,we explored future trends in runoff and hydrological drought in the upper reaches of the Chishui River basin,aiming to provide a scientific basis for ecological conservation,water resource management,and flood and drought disaster prevention within the basin.Based on meteorologi-cal and hydrological data from the upper reaches of the Chishui River during 2000-2019,a Soil and Wa-ter Assessment Tool(SWAT)model was constructed.Utilizing data from five climate models of the Sixth Coupled Model Intercomparison Project(CMIP6)and incorporating the Standardized Runoff Index(SRI)and run theory,we projected changes in climate,runoff,and hydrological drought under two Shared So-cio-economic Pathway(SSP)scenarios(SSP1-2.6 and SSP5-8.5)from 2020 to 2060.Results show:(1)The monthly runoff rate at Maotai hydrological station achieved a coefficient of determination(R2)and Nash sensitivity index(NSE)exceeding 0.8 during both the calibration and validation periods,indicating that the SWAT model demonstrates good applicability in this basin.(2)In the future,the basin will become warmer and wetter.Under scenario SSP1-2.6,precipitation is projected to increase by approximately 10%,and a temperature rise of 0.2℃ per decade,while under scenario SSP5-8.5,the increase in precipita-tion will exceed 20%,accompanied by a temperature rise of 0.5℃ per decade.(3)The annual runoff will increase by 0.009 billion m³/a under scenario SSP1-2.6 and by 0.015 billion m³/a under scenario SSP5-8.5.Under scenario SSP1-2.6,the monthly runoff will increase during both dry and wet seasons,but not ex-ceeding 15%.Under scenario SSP5-8.5,the monthly runoff increases by 10%-20%during the wet sea-son,while decreasing by 15%-30%during the dry season.(4)Under scenario SSP1-2.6,the hydrologi-cal drought frequency decreases,with occasional droughts occurring in spring and winter,while under sce-nario SSP5-8.5 the hydrological drought frequency increases slightly,with a higher probability of droughts in both spring and winter.