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土壤侵蚀是坡耕地土壤退化的主要影响因子之一。在金沙江干热河谷区坡耕地的实验表明， 沿坡耕地等高线种植高密度高固氮植物篱并合理经营，可有效防治土壤侵蚀。１９９７ 年植物篱处理的土壤侵蚀量减少到对照的１４ ．５ ％ ～２３ ．９ ％ ，１９９８ 年侵蚀量仅为对照的１ ％ ～３ ％ 。坡耕地土壤侵蚀集中发生在雨季中期。土壤侵蚀过程也是土壤养分加速流失的过程，分析表明流失土壤中全氮和有机质在侵蚀土壤中含量分别是表土平均含量的２ ．３ 倍和２ ．４７ 倍以上。在培植等高植物篱系统后，经过４ ～７ ａ 的正常耕作，坡耕地可形成以植物篱为地埂的梯地。
Soil erosion is one of the main factors affecting soil degradation on sloping farmland. Experiments on sloping farmland in the dry-hot valley of the Jinsha River show that planting high-density, high-nitrogen-fixing hedgerows along the contours of the sloping farmland and operating them rationally can effectively prevent and control soil erosion. In 1997, the amount of soil erosion after hedgerow treatment decreased to 14% of the control. 5% ~ 23. 9%, 1998 erosion is only 1% to 3% of the control. Slope farmland soil erosion concentrated in the mid-rainy season. The process of soil erosion is also the process of accelerating the loss of soil nutrients. The analysis shows that the contents of total nitrogen and organic matter in the eroded soil are the average contents of the topsoil, respectively. 3 times and 2. 47 times more. After cultivating the contour hedgerow system, after 4 ~ 7 years of normal farming, the sloping farmland can form the terrace with hedgerows as the land.