黄土高原地区中小尺度分布式水文模型

在考虑了降雨和地形特性基础上开发研究了适用于干旱半干旱地区的中小尺度分布式水文模型(THIHMS-SW),依据黄土高原水土保持措施的建设原则,将土壤表层离散为不等厚的数层进行饱和非饱和土壤水分运动数值计算。采用所建模型,对相对天然状态下的岔巴沟流域进行了连续3a的模拟计算。除个别洪峰及较小流域外,得出的模拟计算效果在整个流域范围内均较好,相关系数达到0.84,Nash效率系数达到0.70,峰现时间及最大洪峰流量都得到较好再现。结果表明,模型在黄土高原地区具有较好的适用性。

Distributed hydrological model of small and moderate size watersheds in the Loess Plateau

Taking into consideration of the characteristics of local rainfall and topography, a distributed hydrological model, the Tsinghua integrated hydrological model for small watersheds, was established and used to analyze the water and soil conservation measures in the Chabagou watershed in the Loess Plateau. In the model, the topsoil is categoried into several layers with different thicknesses to calculate the soil moisture movement in saturated and unsaturated zones. A simulation of the hydrological condition for 3 years shows that the predicted largest peak discharges and the time to peak match well with the observed data when the watershed is in a relatively natural state. The Nash coefficients were all higher than 0.70, although more analysis of some specific floods and smaller sub-watersheds is needed to obtain better simulation results.