Abstract:
Guizhou Province, the core of the karst area in southwestern China, is a region characterized by severe soil erosion and rocky desertification, where the characteristics of soil erosion vary across different karst landform types. Taking Guizhou Province as the study area, this study focused on the analysis of the spatiotemporal evolution of soil erosion in Guizhou from 2010 to 2020 by improving the Revised Universal Soil Loss Equation(RUSLE)on the basis of the features of different karst landforms, and to determine the differences in the effects of land use and topography on soil erosion under various karst landform types. The results showed that soil erosion in Guizhou had an increasing trend from 2010 to 2020, with most areas classified as slight and mild erosion. The highest annual erosion (26.96 t·hm
−2·a
−1)occurred in 2015, and the lowest (9.23 t·hm
−2·a
−1)in 2011. The leading factors and interactive factors of soil erosion were identified by the geographic detector method, with the interaction between land use and slope playing a predominant role. Among the landform types, the highest erosion rate was observed in karst trough valleys(22.32 t·hm
−2·a
−1), while the lowest in karst plateaus(15.80 t·hm
−2·a
−1). Under the karst trough valley landform, the soil erosion rates for cultivated land, shrubland, and sparse woodland reached 31.05, 19.62 and 16.97 t·hm
−2·a
−1, respectively. Within the same karst landform type, the erosion increased with the slope, however, the responses of soil erosion to slope differed depending on the changing karst landforms.The response of the karst gorge to slope was significantly stronger than ones in other karst regions. Compared with the average soil erosion on slopes below 5°, that on slopes exceeding 25° increases by 97.48%, those in other karst regions increased by 60.00% to 80.00%. This study elucidates the effect of landform types and land use on soil erosion in karst regions, which is of important theoretical and practical significance for effective erosion control in these regions.