Study On The Watershed Rainfall-Runoff Model Based On The Effort Of Forest

The problem of the relationship between the forest and the water is always the keyproblem of forest ecological system research, and also is one of the important content of thehydrologic cycle exploration. Time and space distribution of moisture, transmissionconversion and the influence of the hydrologic cycle mechanism that forest ecological systeminfluence are the cores of the forest hydrology research. The relationship between the forestand the water is very complex, it is not only influenced by forest ecological systemdevelopment, but also by mountain air, plants, soil, underground strata heterogeneity andspace such as the factors such as rainfall evaporation, time and space change, which increasethe difficulties of the forest describe runoff forming mechanism and hydrological responsepattern. In the background of global climate change, human activity intensifies; frequentchange under the cushion basin time and space distribution, hydrologic vegetation changes tothe response of the various fields has become a hot issue.The research about the effect on runoff by the change of forest vegetation has importantsignificance on the forest management and water resources reasonable and the sustainableutilization of forest ecological environment and for maintenance and ecological balance. Thisthesis aims to small watershed forest hydrological characteristics, in combination with rainfallrunoff model theory, on the basis of runoff formation, considering the forest vegetationchanges; establish the small watershed forest rainfall runoff model which revels thecharacteristics. In this paper take the Hun-River upstream watershed forest for example, usethe forest coverage rate and volume of forest vegetation influence as rainfall runoff model ofthe two indexes, according to the forest coverage rate that is more than60%on average andalso the average volume of forest vegetation that is more than5000m~3/km~2and the forestcoverage rate that is less than60%, and also the average volume of forest vegetation that isless than5000m~3/km~2divided into two levels to rate parameters. The results which this paperstudied are as follows:(1)Combined with the wetted area using the experience of stored-full runoff model andmethod of determining parameters, the thesis present the reflect the state of forest vegetationcharacteristics of forest watershed rainfall runoff model。It improves the previous in forestareas without considering the impacts of forest vegetation on rainfall-runoff calculation.(2) Forest vegetation better, more stable infiltration rate, underground runoff is more a,this reveals the forest vegetation which enhances the soil infiltration capacity and reflects theproportion of runoff components. In the watershed confluence, basin water storage coefficient, flow parameters are different, the flood process line reflected peak flow difference.(3) Based on the measured data, the simulation calculation and test, the computationalresults are compared, the model not only has good accuracy, but also can roughly reflect thetwo different forest vegetation on water conservation, regulating flood effect. The model hasstronger practicability, and provides the forest hydrological function deepening study to drawlessons from action.