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楚雄市的土地退化以水蚀为主要动力，在云贵高原具典型代表性。全市退化土地面积１１５９．４４ｋｍ２，占总面积的２６．１７％。土地退化的危害有：降低土壤肥力，冲断桥梁，加剧自然灾害，毁坏水利工程。其形成原因中自然因素是：地形破碎，降水分布不均匀，地表物质疏松；人为原因是：人口快速增长增加对土地的压力，导致乱垦坡地，砍伐森林和超载放牧。
Chuxiong’s land degradation takes water erosion as the main driving force, with typical representative in Yun-Gui Plateau. The city’s degraded land area is 1159.44km2, accounting for 26.17% of the total area. The hazards of land degradation are: reducing soil fertility, breaking bridges, exacerbating natural disasters and destroying water conservancy projects. The natural causes are as follows: the terrain is fragmented, the distribution of precipitation is uneven and the surface material is loose. The man-made reason is that the rapid population growth increases the pressure on the land, resulting in indiscriminate cultivation of slopes, deforestation and overgrazing.