Integrated model for surface water and groundwater in arid inland river regions and its application

On the basis of hydrodynamics an integrated model for simulating the coupling of surface water and groundwater is established.The scale problem happened to coupling of surface water model and groundwater model,the problem of determination of base flow and the method of moving water table are investigated.The validity of the model is verified by the simulation result of typical examples of 1-D open channel flow,1-D and 2-D saturated-unsaturated flow of groundwater.Finally,the model is applied to analyze the interchange between surface water and groundwater in the middle reaches of Heihe River,which is an inland river located at the arid region of China.The result shows that in the upper reaches of the river about 17% water is infiltrated,about 30% of incoming water of Yingluo Gorge river section located at the downstream of the Heihe Bridge is obtained from groundwater and the spring water coming from groundwater is gradually decreased year by year.