水土流失是环境日益恶化和制约可持续发展的重要原因 ,而坡耕地则是水土流失的重要策源地。长江等河流的泥沙6 0 %～ 70 %源于坡耕地 ,如何有效治理坡耕地水土流失 ,是有效实施我国西部生态环境建设的前提。为防治坡耕地的水土流失 ,坡改梯得到了大力推广和政府的支持 ,但其局 Soil and water loss is an important reason for the deteriorating environment and restricting sustainable development. However, sloping farmland is an important source of soil and water loss. From 60% to 70% of the sediment in rivers such as the Yangtze River stems from sloping farmlands. How to effectively control soil erosion on sloping farmland is a prerequisite for the effective implementation of the ecological environment in western China. In order to prevent and control the soil and water loss in sloping arable land, the slop and ladder upgrading has been vigorously promoted and supported by the government. However, its bureau