滇中地区土壤侵蚀时空变化及多尺度驱动因子OA

[Objective]As a critical ecological barrier in the upper reaches of the Yangtze River,the central Yunnan region faces prominent soil erosion issues.Investigating the multi-spatiotemporal evolution patterns and multi-scale driving factors in this region is of great significance for guiding subsequent soil erosion control and sustainable ecological restoration.[Methods]Based on the RUSLE model and GIS/RS technology,this study quantitatively inverted the spatiotemporal dynamics of soil erosion in central Yunnan region from 1990 to 2022.The geodetector method was employed to systematically analyze the driving factors of natural and anthropogenic effects on soil erosion at two scales:the regional scale and the sub-basin scale.[Results]1)Soil erosion in central Yunnan region was dominated by slight and light levels.Spatially,it showed a distribution pattern of"strong erosion in the northeast and river valleys,and weak erosion in the northwest."Temporally,it exhibited a trend of"overall contraction with intensified extreme erosion."2)At the regional scale,fractional vegetation cover(-q=0.290)and land use type(-q=0.156)had the highest explanatory power,and fractional vegetation cover combined with slope constituted the dominant driving combination(-q=0.557).At the sub-basin scale,the interaction effects of fractional vegetation cover and slope(-q=0.603)and land use type(-q=0.517)increased significantly,and the impact of human activities strengthened as the scale decreased.High-risk areas were mainly distributed in grassland regions with elevations of 1 000-2 000  m,slopes> 35°,moderately weathered strata,and fractional vegetation cover of 10%-30%.[Conclusions]The findings reveal the scale dependency and heterogeneity of driving factors of soil erosion in central Yunnan region,which can provide a scientific basis for differentiated and precise soil and water conservation measures.