Abstract:泾河流域人为新增水土流失呈逐年增加趋势。最大的增洪增沙是开荒 (包括陡坡开荒和毁林开荒 )。 90年代人为年均增洪 15 10万 m3 ,年均增沙 146 5万 t,比 80年代分别增加 2 6 .4%和 40 .2 % ;比 70年代分别增加85 .3%和 6 9.0 %。制止人为新增水土流失刻不容缓。西部大开发 ,生态环境建设必须同步 ,才能实现泾河流域国民经济和社会的可持续发展。

Abstract:The article analyzed the feature of soil and water loss in southern region, and appraised systematically the effects of furring mulches on controlling soil and water losing. It could be concluded that vegetation construction based on furring mulches is a new way to controlling soil erosion in southern region.

Abstract:Based on the data of Guojialiang test site, we built up soil erosion and sediment yield models and erosion control models of the hedgerow. The study produced water and sediment transport networks of the catchment from digital elevation model (DEM) and brought them to the models. The combination of GIS and models simulated the influence of upper runoff to the blower slope and the spatial process of runoff and sediment transport in a catchment. The result of the simulation from 1995 to 1999 showed that the cultivated slope land, bare slope land and natural grass land with low vegetative cover have the highest erosion modulus in Qingbiankohe catchment, and they are the important regions for erosion control. We simulated the system of the hedgerow crops in these regions whose areaonly has 18.2% of the whole catchment. The results shows that the control effect for runoff is between 8% and 46% and the control effect for sediment is between 42% and 50%. The simulation results of nutrient loss showed that the loss of the organic matter is severe on the current conditions. However, it is a efficient method to control the nutrient loss on the condition of hedgerow crops system.

Abstract:Sustainable land use has ever been the same aim of all country government and ecology scientists. However, in reality, theory and method of sustainable development cannot always be implemented into actual land use. One of the main cause is, most research confined in natural branch has emphasized on "what and how should be done" and neglected "what and how is done in reality". On the base of analysis of farmers inspect and investigation on the spot in Mu Us Sandland, a study of actual land use decision making processes and influential factors in that process was paid to the arid and semi arid zone, Northwest China. Differences of those three social groups on standpoint, view and influential force in the process of land use decision making were discussed.

Abstract:Husbandry, as the backbone industrialization of the Loess Plateau, its sustainable development must follow the listed principle: It is prerequisite that farm must provide enough food by improving the yield per area and environment must to be maintained and improved, then farmer' income probably be improved and the poverty status be changed. At the same time sustainable development need to solve the inner contradiction of husbandry, optimize and harmonize the outside condition i.e. the support of economic, social and technique system.