喀斯特流域近40年不透水面变化特征及其对地表径流的影响OA

[Objective]To provide a scientific support for optimizing territorial space,flood risk management and agricultural security in karst mountainous areas.[Method]This study examines a typical karst watershed using remote sensing data(1985-2022)and integrates the SCS-CN hydrological model,multiple linear regression,and geostatistical methods to analyze the spatiotemporal dynamics of impervious surface ex-pansion and quantitatively simulate its effects on surface runoff and flood inundation extent over the past four decades.[Result]The results show that impervious surface area increased from 3.31 km2 to 22.05 km2,with spatially contiguous growth along the northwest-southeast axis.Surface runoff exhibited a strong positive correlation with impervious surface coverage,showing more pronounced increases under low-intensity rainfall.Flood-prone areas progressively shifted from low-lying farmland downstream to urban zones in mid-upper reaches,endangering agricultural land,urban infrastructure,and arable resources.[Conclusion]The study underscores the critical need for impervious surface scientific manage-ment in karst regions to coordinate urban development and mitigate urban flooding risks.These findings provide a scientific basis for territorial spatial planning and sustainable agricultural development in karst mountainous areas.