Study On Rainwater Resources Utilization And Its Effects On Eco-environment In Sanchuanhe Basin

On the evaluation of water resources, only the sum of the surface water and groundwater which don't repeat each other are considered, the rainwater hasn't been appraised as the total amount of water resource. In fact, rainwater is the renewable and liquid fresh water, and can be utilized. So rainwater totally accords with the definition of the traditional water resource, and it ought to be dealt with as total amount of water resource. Through the rich collection on space and time, rainwater can well become strong supplement of surface water and groundwater. And in the particular area, such as the Loess Plateau, rainwater has already become a kind of irreplaceable water resources utilization form. In the thesis, the study object is Sanchuanhe basin that is the first level branch of Yellow River basin, its total area is 4161km2, and the new concept that regards the annual precipitation of the district as total amount of water resource meets the water resource characteristic of the Loess Plateau, it is the theoretical foundation of this research.beginning with the potential of rainwater resources and the regional society, economy and ecology, the near and far future planning of the underlying surfaces are designed, the index system of the rainwater resources utilization is determined for big area, and the plannings on the basin are evaluated scientifically, the present status and the near and far future planning of the rainwater resources utilization are analyzed and evaluated in the basin. On the basis, through the analysis of long-term monitoring data of the hydrometric station in Sanchuanhe basin, the effects on eco-environment such as the benefit on soil and water conservation in different periods are appraised. And the following basic conclusions are drawed.1. It is the research basis of the potential of rainwater resources utilization in Sanchuanhe basin how to determine the index system of the rainwater resources utilization for big area. On the foundation of integration analysis of the water storage and silt detention, the index system on water storage and silt detention in sub-region two of the first pair of districts of loess hilly and gully region is summed up, and the index system on the rainwater resources for big area is obtained from this. The index system includes local utilization potential, actual runoff, discount factor of slope runoff and runoff potential. The scientific basis is established for the research of the potential of rainwater resources utilization in Sanchuanhe basin.The index system includes the all underlying surface types. In order to improve the...