长江上游重点水土流失区陡坡耕地的出路

长江上游重点水土流失区坡耕地面积５４９１ 万ｈｍ２ ，占耕地面积的６２８ ％ ，其中＞ ２５°的陡坡耕地约占坡耕地面积的１／５ 。坡耕地全部退耕还林影响群众生活，而且可能会加剧冲沟侵蚀。宁南县将一些２５°～３０°的陡坡地集中连片改造为梯地，并配套有较完善的坡面水系工程，不但有效防治了水土流失，而且作物产量和产值大幅度提高。因此，长江上游重点水土流失区＞ ２５°的陡坡耕地退耕还林工作不能一刀切。光热条件好、人多地少的地区，可以将２５°～３０°的陡坡地集中连片改造为梯地，配套完善的坡面水系，以取得良好的生态、社会、经济效益。

The Way Out for Steep Land in Focal Areas With Severe Soil and Water Loss in the Upper Yangtze River

There are 5 491 000 hm 2 of slope land in severe soil and water loss region in the upper Yangtze River that accounts for 62.8% of total farm land, in which one fifth of them is steep slope land with slope grade over 25 degree. If all the slope land is forested from cultivation, the local people's life will be influenced and furthermore the gully erosion may be intensified. Some of the steep slope land with grade of 25 to 30 degree have been constructed to be terrace in large scale and equipped with perfect slope water system projects, which not only controls soil and water loss but also significantly increases grain production and output. Therefore, we should not take only way to forest the cultivated land on steep slope of larger than 25 degree in the severe soil and water loss region in the upper Yangtze River. In the areas of more population density and less land as well as with favorite heat and light conditions, the steep slope land with grade of 25 to 30 degree can be improved into terrace in large scale and completed with slope water system in order to achieve good ecological, social and economic effects.