退圩还湖工程后水系连通分析——以平旺湖、得胜湖为例

Analysis on the connectivity of the water system after the project of returning polder area to lakes: Taking Pingwang Lake and Desheng Lake as examples

兴化市位于里下河地区腹部,其列入《江苏省湖泊保护名录》中的湖泊湖荡共有20个。目前这些湖泊存在开发围占、水流堵塞及生态系统恶化等问题,严重削弱湖泊调蓄和湿地功能。退圩还湖工程对湖泊范围内占用圈圩进行清退,从而扩大湖区自由水面面积,改善水环境。以平旺湖、得胜湖为例,通过构建里下河平面水网模型的方法,分析退圩还湖实施后成湖区的流场分布。结果显示,退圩还湖后水流顺畅,湖体中部水流流速大,边界处由于口门换水,不易产生淤积,整个湖体设计对生态改善有积极影响。

Xinghua is located in the abdomen Lixia river region where a total of 20 lakes were taken in the"lake protection list of Jiangsu province".At present,there were problems such as development and occupation,water flow blockage and ecosystem deterioration,which seriously weakened the functions of lake storage and wetland.The project of returning polder area to lakes cleared the occupied areas in the lake area,thereby expanding the free surface area and improving the water environment.Taking Pingwang Lake and Desheng Lake as examples,the method of constructing a water network model for the Lixia River was used to analyze the flow field distribution of the lake area after the implementation of returning polder area to lakes.The results showed that the water flow was smooth and the flow velocity in the middle of the lake body was high after returning polder area to lakes.Because of the change of water at the mouth of the lake,it was not easy to deposit,and the design of the whole lake body had a positive impact on the ecological improvement.