洞庭湖区间径流模拟

Modeling of interval runoff in the region of Dongting Lake

洞庭湖对长江中游洪水有着重要的调蓄作用,其调蓄能力不仅受到湖区面积和容积的限制,还受到其上游四水来水和区间洪水的影响。四水来水可通过水文控制站实测,但是区间洪水难以估计。在洞庭湖洪水模拟中通常忽略区间洪水或做简单概化处理,从而影响了洪水模拟精度。本研究以洞庭湖区间洪水模拟为目标,根据洞庭湖区间流域的特点,将洞庭湖区间划分为山丘区与堤垸区,根据其不同的产汇流特点,分别采用分布式水文模型GBHM和基于栅格的新安江模型进行模拟,并利用洞庭湖水量平衡对模拟结果进行间接验证,结果显示区间洪水模型具有较高的模拟精度。

The Dongting Lake plays an important role in regulating and storing the flood of Yangtze River.Its storage capacity is limited by its surface area and volume,and also by the flows from its upper four reaches and from the polder region.The runoffs from the four reaches can be measured by hydrological stations,while the lake＇s inflow from the polder region is difficult to estimate.In this study,the polder region was divided into a hillside area and an embankment area,and by the difference in their runoff features a distributed hydrological model GBHM and a grid-based Xin＇anjiang model were used for simulation,respectively.The results were indirectly verified by the principle of water balance,and the verification shows a relatively high accuracy of this model.