本文选择我国水土流失最为严重的黄土丘陵沟壑区作为研究地区,通过野外调查、土地利用填图,结合区域国民经济发展规划提出了4种基本土地利用规划方案附加2种保护性耕作措施;开展了生态适宜性、经济可行性和社会可接受性评价。提出:在得到大量外部经济支持的前提下,应积极实行15°以上的坡耕地全部退耕还林还草的方案,其中在中等坡度的地区(15°-25°)应发展果园和经济林;若缺少外部强有力的经济支持,该区土地利用调整应逐步开展,短期内(约0-5年),建议坡度大于25°的坡耕地逐步退耕还林还草,其中,坡度大于25°,地形条件较好的地区应种植果园和经济林;中期(约5-10年),坡度大于20°的黄土地区应逐步退耕还林还草,其中坡度介于20°-25°之间的地区应转变为果园和经济林;10年之后,建议大于15°的坡耕地全部转变为其他用途,其中坡度介于15°-25°的黄土地区应转变为果园和经济林,坡度大于25°的地区转变为林地/灌丛和草地

With population growth and arable land decrease, the pressure of human activity on land resource is becoming greater. How to realize sustainable land use has become the focus of global society. Both the time scale and spatial scale have to be concerned when a sustainable land use planning was made. Normally, ecological suitability, economic feasibility and social acceptance of land use scenario have to be considered. Currently, most works concern more on theoretical aspect of sustainable land use rather than some practical approaches to realize sustainable land use. In this study, a procedure for carrying out such a planning is presented, based on results from a research project in a small catchment on the Loess Plateau. A land suitability evaluation for rainfed agriculture based on biophysical parameters, and a comparison between land suitability and current land use, were first carried out. Some potential land use scenarios, based on surveys on biophysical and socio-economic parameters in the catchment, and plans by the authorities, were proposed for further evaluation of their effects on soil erosion, economic feasibility and social acceptance. The results indicated that the following land use scenario was acceptable: all land with deep soil and slopes smaller than 15° is used for agriculture cropland, possibly combined with biological conservation measures, such as mulching combined with improved fallow, and all land with slopes steeper than 15° is used for other purposes (orchards and other cash trees, woodland, shrubland, grassland). A great reduction of on-farm income, however, would be induced on the short term by such a scenario. Local farmers will find it difficult to accept unless financial support from external sources is available. On the long term, the scenarios will be promising for both economic income improvement and soil erosion control since some production will be obtained from the conversion of cropland into orchards/cash trees (preferably on slopes 15～25°). Thus the land-use modification should be carried out gradually. On the short term (5 year), it is suggested that cropland on slopes steeper than 25° is returned to woodland/shrubland/grassland while also fruit trees are planted on slopes of 15～25°. Within 10 years, cropland with slopes steeper than 15° is suggested to be converted into orchard/woodland/shrubland/grassland.