近二三十年来,在全球范围内,人类为实施水土保持计划投入大量资金并付出巨大的代价,相反,其投入的效益却日趋下降,受侵蚀的地区和其它形式的土地退化面积不断增加.因此,水土保持专家和援助机构开始探讨水土保持项目的效益.在近十年来,国际水土保持团体,通过对过去水土保持失败教训的反思与分析,开始以新的思维方式探讨水土保持的发展战略. Over the past two decades or so, mankind has invested heavily in and paid a huge price for implementing soil and water conservation plans on the global scale. On the contrary, the efficiency of its investments has been declining. Areas under erosion and other forms of land degradation have been continuously increasing. Therefore, soil and water conservation experts and aid agencies started to explore the benefits of soil and water conservation projects.In the past ten years, the international soil and water conservation groups started to explore the development strategy of soil and water conservation with a new way of thinking through the reflection and analysis of the lessons of failure of soil and water conservation in the past .