基于RUSLE模型的孙水河流域土壤侵蚀空间分异特征

土壤侵蚀一直是我国开展区域生态环境治理所关注的热点问题之一。在RS和GIS技术支持下,基于RUSLE模型分析了凉山州孙水河流域不同土地利用类型、海拔和坡度条件下土壤侵蚀强度的特征,定量评价了研究区土壤侵蚀空间特征。结果表明:孙水河流域平均土壤侵蚀模数为1 954.32 t/(km~2·a),土壤侵蚀严重区域主要集中于孙水河干流及其支流沿岸;坡耕地和中覆盖草地是流域内主要侵蚀土地利用类型;海拔2 000～3 000 m流域土壤侵蚀较为严重,平均土壤侵蚀模数超过2 000 t/(km~2·a);当坡度低于25°时,土壤侵蚀模数随着坡度的增加而增大,15°～25°是该流域侵蚀最为严重的地带。研究成果可服务于凉山州孙水河流域水土保持治理工作,为实现乡村振兴提供一定理论支持。

Research on Spatial Variation of Soil Erosion in Sunshui River Basin Based on RUSLE Model

Soil erosion has always been one of the hot issues that China has paid attention to when developing regional ecological environment management. With the support of RS and GIS technology, this study analyzed the characteristics of soil erosion intensity under different land uses, altitudes and slope conditions in the Sunshui River Basin of Liangshan Prefecture based on the RUSLE model, and quantitatively evaluated the spatial characteristics of soil erosion. The results showed that:(1) The average soil erosion modulus of the Sunshui River Basin was 1 954.32 t/(km²·a), and the areas with severe soil erosion were mainly concentrated along the mainstream of the Sunshui River and its tributaries. (2) Moreover, the slope farmland and middle-cover grassland were the main types of eroded land use in the watershed. Soil erosion in the 2 000~3 000 m altitude zone of the basin was more serious, with an average soil erosion modulus exceeding 2 000 t/(km²·a). (3) Furthermore, the soil erosion modulus increased with the increases of slope, and 15°~25° was the most severely eroded zone in this watershed. We expect that these research results could serve the water and soil conservation and management work of the Sunshui River Basin in Liangshan Prefecture, and provide certain theoretical support for the realization of rural revitalization.