Influence of the Morphology and Spatial Distribution of Exposed Bedrock on Soil Erosion on Karst Slopes

［Objective］ By studying the influence of the morphology and spatial distribution of exposed bedrocks on soil erosion on karst slopes, it is helpful to deepen the understanding of erosion laws under natural rainfall conditions on karst slopes, and to provide a reference for rocky desertification control in karst areas. ［Methods］ Through the monitoring of natural rainfall, the effects of natural rainfall, the morphology and spatial distribution of outcropping bedrock on the sediment production of karst slopes were studied by taking different rock-soil covered slopes as the research objects. ［Results］ 1) The change in the morphology of exposed bedrock could significantly affect surface runoff, and such effect was rain-intensity dependent. 2) The morphology of exposed bedrock was one of the key factors in the dynamic changes of soil flow, and the spatial distribution of bedrock significantly affected the formation of soil flow under different rainfall intensities. Among them, the aggregation distribution (R-type) was the most conducive to the generation of soil flow.3) The change of bedrock morphology mainly affected the underground runoff under the conditions of light rain and moderate rain, while in large-scale rainfall events (such as rainstorm and heavy rainstorm), the spatial distribution pattern of bedrock was closely related to the formation of underground runoff. 4) The morphology and spatial distribution of exposed bedrock played an important role in soil erosion and sediment transport during extreme rainfall events. ［Conclusion］ The morphological changes of exposed bedrock significantly affect the trends of surface runoff and soil flow, and such effects vary with rainfall intensity. In the future, soil erosion control measures should be taken according to different rainfall types.