半湿润地区河滩湿地水文特性的模拟研究

Simulating hydrological characteristics of riverine wetlands in semi-humid regions

本文利用DRAINMOD模型模拟分析了泾河-渭河-灞河交汇区不同宽度河滩湿地受河道水位变化影响的水文过程。结果显示，河道水位变化和滩地宽度对河滩地湿润程度以及河道排水，补水过程的影响较复杂。一年之中，由于河道水位变化以及降雨分布的不同会出现交替的补水，排水现象；而年际间，丰水年河道的排水效果明显；河道对滩地的补水主要发生在河道水位很高而降雨平均或稀少的年份，在河滩宽度很小的情况下，河道向滩地的补水量可以达到16～21cm，约为当地年平均降雨量的1／3。同时，研究结果还显示，在平均河道水位条件下，河道向湿地的补充水量有限，不能有效提高湿地湿润状态。

The DRAINMOD model was used to analyze hydrological characteristics of a riverine wetland with different widths affected by the variation of fiver channel water level at the confluence of Jinghe River-Weihe River and Babe River in Shanxi Province, China. The result shows that the effects of water level variation and wetland width on the wetness of wetland and drainage/recharge process are very complicated. The river channel drains or recharges the wetland alternatively in the period of a year due to the variations of water level and precipitation. In the year with abundant rainfall the effect of drainage is obvious. In the year with annual precipitation lower than average level, the effect of recharge from river takes place when the water level in river channel is relatively high. When the width of wetland is narrow, the recharged water amount may reach 16 - 21cm, which is about 1/3 of the average annual precipitation. Further investigation shows that under the condition of average water level the effect of water recharge is not significant, the wetness of wetland can not be elevated.