基于GIS方法的泸沽湖流域水土流失敏感性评价

泸沽湖流域具有珍贵的高原生物和独特的摩梭族文化，但随着旅游开发的加快，水土流失风险开始显现。研究基于RS和GIS技术，选取土地利用类型、坡度、沟谷密度和土壤4个影响因子，对泸沽湖流域水土流失敏感性空间分布特征进行了分析评价。结果表明:不敏感和轻度敏感区占流域总面积的52.61%，反映泸沽湖流域水土流失保持现状基本良好；但仍存在明显的水土流失风险及空间差异，中部敏感区占流域总面积的38%，而高度和极敏感区占流域总面积的9.39%；高度和极敏感区主要分布在环湖带，影响因素除了坡度较高外，筑路和开垦农田等人类活动导致的土地覆被变化及易侵蚀土壤类型是局部区域重要的影响因素。研究结果可为泸沽湖流域水土流失防治和生态保护提供科学依据。

GIS-Based Assessment on the Sensitivity of Soil and Water Loss in Lugu Lake Watershed

There are many rare alpine species and a unique matriarchal culture (the special Mosuo culture) in the Lugu Lake Watershed. Lugu Lake is a deep alpine fresh water lake with first class water quality. However, with the rapid development of tourism, the risk of soil and water loss has begun to be found. In this study, land use types, soil types, gully density and geographic gradient were selected as indicators used to assess the soil and water loss sensitivity. Based on RS and GIS technology, the spatial distribution of the soil and water loss sensitivity of the Lugu Lake Watershed was studied. The results show that 52.61% of the watershed is insensitive and slightly sensitive, 38% of the watershed is moderate sensitive and 9.39% of the watershed is strong sensitive or extremely sensitive. There are significant differences in the spatial distribution of the soil and water loss sensitivity in the Lugu Lake Watershed and the strong and extreme soil and water sensitive areas mainly distributed around the lake. The change of the land cover caused by human activities (such as road construction and farming) and the easily eroded soil are the important impact factors on local high soil and water sensitivity. Our study provides useful references for the prevention and control of soil and water loss and the ecological conservation in the Lugu Lake Watershed.