Application Of Distributed Hydrological Model To Water Integrated Management In Weihe River Basin

The Weihe River basin, as the largest tributary of the Yellow River, mainly covers the Loess Plateau that geographically belongs to the semi-arid area. In the latest decades, the basin is characterized by fragile natural environment, extremely deteriorating ecological environment, serious soil erosion, frequently drought, coupled with severe scarcity of water resources and water pollution and the decrease in some species even distinction, which has become a key obstacle to the sustainable consumption of the waters resources along the basin, and bottlenecked the social and economic development of Shannxi Province.Presently, the distributed hydrological model began to be applied to the small-scale watershed. The integrated management and distributed hydrological model have been applied to many small watersheds in China and abroad. GBHM₂ model (developed by Yang Dawen from Tsinghua University) is selected as the methodology of the thesis after referring to the various similar study cases, with the attempt to simulate the water hydrological information of the Weihe River basin for its comprehensive management.Primarily, the digital elevation model(DEM) of the Weihe River basin is set up; based on it the overall watershed of the basin is extracted. Considering the natural distribution of its tributaries, the overall watershed is grouped into 65 sub-watersheds, and meanwhile each sub-watershed is divided into a series of hillslope elements as the minimum study unit of GBHM₂. According to GBHM₂ model system, two categories of database including the spatial and attributive information of the Weihe River basin are obtained with the assistance of GIS and some other statistical literatures. This model is applied to simulate the total water quantity of the Weihe River in different inputs and the spatial and temporal distribution characteristics of the current runoff and precipitation of each sub-watershed; the study results are sound. Finally, based on the pollution load and distribution characteristics of each sub-watershed, together with the analysis of simulated results of daily runoff, the program of reducing pollution load for each sub-watershed is put forward respectively. The thesis will be a valuable reference to the policy-making body of the Weihe River basin. Moreover, the thesis provides a detailed technical pattern for an overall pollution harnessing and management of water resources concerning the basin.