Finally , by using of the mathematical model , it is calculated and predicted the effect of the different tongguan riverbed elevations as well as the different conditions of incoming water and sediment on the variance of the flood elevation and the tend of aggradation and degradation of the lower weihe river bed . it is answered quantitively the lessening extent of sediment silt and the decreasing extent of the flood elevation of the lower weihe river after 14 years on two different incoming water and sediment conditions with three different tongguan elevations , respectively 328m , 327m and 326m . these results supply important references to the planning of flood control and comprehensive regulations of the weihe river basin 最后用验证后的数学模型对不同水沙系列、不同潼关高程( 328m 、 327m 、 326m )下渭河下游的冲淤趋势和洪水位的变化进行了预测计算，从定量上回答了潼关高程从328m降至327m (相当于潼关高程降1m )和潼关高程从328m降至326m (相当于潼关高程降2m )时，渭河下游14年之后各河段的减淤程度以及不同流量级洪水位的降低幅度，这些成果对于渭河下游防洪治理规划的制定具有重要的参考价值。
