Study On The Ecologuical Response Of Hydrology On Forest Vegetation In Some Typical Watershed In North China

The forest vegetation which have huge hydrology function such as restrainting headwaters,regulating flows,improving water quality,protecting soil and water environment, so the forest vegetation ecological construction is the critacal path to resolving the problem of water resources and water environment.This thesis chooses Banchegnzi watershed,Shachang watershed and Huairou watershed in north China as examples research area, imitating and studying the runoff in the research area with the application of distributed hydrological model SWAT(the Soil and Water Assessment Tool), and stressing on the influence of forest vegetation change to ecological hydrology responds.Based on the information data of land use, soil classification, hydrology and meteorology, SWAT model (Soil and Water Assessment Tool) is applied to simulate the eco-hydrological process in Banchegnzi watershed,Shachang watershed and Huairou watershed. LH-OAT sensitivity analysis and SCE-UA automatic model calibration were implemented in SWAT 2005 version. This thesis is the first employed these two new functions to calibrate and validate the parameters quickly and accurately in north China. According to the model evaluation results, it shows that SWAT model could be successfully used to simulate the hydrological process in in north China.According to the analysis result of SWAT model, applying the GIS spatial analysis function, the thesis analyze the special distribution of runoff in 1990,1995, 2000 and 2005 about the contribution of hydrological respondes by different kinds of forest vegetation. The result showes that the forest vegetation deeply influence the runoff.The more rainfall in a month, the more runoff; contrarily is the opposite. The change of landuse mainly expresses in the decrease of the shrubbery and conifer area and the increment of the broadleaf area, the relative hydrology change is the decrease of runoff. Through the prediction of forest vegetation in 2010,establishment of scenery model, different analysises are carried on the influence of hydrology responds with different forest vegetation cover . The result showes that forest vegetation cover have evidence ecological hydrology function of reducing runoff.