Distributed model of hydrological cycle system in Heihe River basin I.Model development and Verification

The GIS technique is applied as a data processing plateform to develop a distributed model for simulating the hydrological cycle system in the Heihe River basin,namely WEP-HeiHe.The physical mechanism of hydrological cycle and the artificial system of water utilization in the basin are considered.The structure of the model is introduced.The simulation consists of two aspects: hydrological cycle and energy cycle.The hydrological process components include evapotranspiration,infiltration,runoff,movement of ground water,interaction between groundwater and river water,overland flow,river flow and artificial cycle process of water utilization.The parameters of the model are calibrated by 5 years runoff data obtained from the Yingluoxia Hydrological station.The validity of the model is verified by the simulation calculation of runoff variation process in 1981 to 2002.It shows that the proposed model can be applied to forecast the evolution of river basin water resources under the conditions of changing environment.