During the process of preliminary designing for soil and water conservation of the Yufeng watershed, Suining city, Sichuan province, ArcView, one software of Geographic Information System, is applied to complete the spatial analysis, to obtain the fundamental data of prelimilary design for soil and water conservation, to map and print required layouts, and to make the system demonstration.

Taking Xingfeng watershed as a case,its watershed basic unit concentration flow is simulated and the results are satisfactory.

Characteristics of typical rainstorm,flood and sediment yield in Luoyugou Watershed;

This thesis chooses Luoyugou watershed in Gansu province Tianshui city as the example research area,imitating and studying the runoff,sediment and water quality in the research area with the application of distributed hydrological model SWAT(the Soil and Water Assessment Tool),and stressing on the influence of precipitation and forest vegetation change to ecological hydrology responds.

Buxus rugulosa community being first discovered in Yuqu River Basin in Tibet;