• Complex river system;
  • unclosed river basin;
  • Wei River


As the largest tributary of Yellow River and the ‘Mother River’ of Guanzhong Plain in Shaanxi Province, Wei River plays a great role in the development of West China. The lower reach of Wei River is the key economic district of this region. In this study, TOPMODEL with infiltration excess runoff was modified and applied to simulate inflow process between the Xianyang and Huaxian (outlet of the study area) hydrological stations for an unclosed river basin with a complex river system as well as ungauged tributaries. At the Qinduzhen and Muduwang hydrological stations, the Nash-Sutcliffe efficiencies were between 0.70 and 0.84, and the relative errors were between −2% and 12%. Integrated with the observed streamflow in Jing River and Shichuan River and the segmented Muskingum flow routing method, streamflow at Huaxian was simulated. Comparison of the simulation results with and without the south inflow showed that the simulated streamflow at Lintong hydrological station with the south inflow between Xianyang and Lintong was closer to the observed streamflow than the one without the south inflow. However, the difference between the simulated streamflow at Huaxian with and without the south inflow was insignificant. This demonstrates that the streamflow simulation at Lintong is important for simulating flows in the study area with reliability.