洞庭湖区退垸还湖的防洪效应

Flood Preventing and Controlling Influence of Recovering Flood Storages of Dongting Lake

以1954年汛期来流资料及1995年实测地形资料为背景,采用洞庭湖区洪水调度数学模型定量分析了退垸还湖对湖区调蓄量及长江中游的防洪影响,并对湖区不同部位平退对调蓄量和洪水位的影响进行比较。结果表明,退垸还湖可以减轻洞庭湖区及长江中游的防洪压力,对距离城陵矶较近的垸区采取退垸还湖措施对城陵矶水位影响相对大一些。

Dongting Lake is well-known for its flood preventing function in the mid-reach of the Yangtze River and its flood storage capacity is very important for the flood control. In practic, to enlarge the flood storage capacity of Dongting Lake is one of the most important flood control measures for the mid-reach of Yangtze River, Therefore, the area of Dongting Lake must be enlarged, which is one of the most important factors that affect the flood storage capacity. On the contrary, the reclamation cuts back the flood storage capacity. Many specialists have done much work about recovering the flood storages. However, it hasn't been studied that different part of Dongting Lake has different effect on flood control. The present paper has given analysis of not only the flood control influence of recovering the flood storages but also the change of the flood-level after retreating the flood storages in the different part of Dongting Lake.It can be concluded that recovering the flood storages can obviously bring down the flood-level of Dongting Lake and the mid-reach of Yangtze River, and that the flood storages nearer Chenglingji play a more important role in bringing down the floodlevel, that recovering the flood storages nearer Chenglingji is more important for flood control.