【摘要】 江湖水系连通是改善水环境、修复水生态和提高人居环境的重要措施,但有关城市内湖水系连通工程的动态连通性定量评价不够完善。基于岳阳城区芭蕉湖-南湖连通工程方案,从长江引水至芭蕉湖通过王家河流域新开挖河道自流至南湖,以改善王家河和南湖水质状况与修复水生态功能。采用MIKE21水动力模型分别模拟汛期和非汛期时6、12和24 m~3/s的流量条件下,南湖出口最低控制水位为25.86 m和26.06 m的12种工况,分析不同引水条件下两湖的连通性,并提出一个定量评价指标。结果表明:引水初期流量取24 m~3/s和控制南湖出口最低水位为25.86 m时,汛期和非汛期连通性均达最佳状态,此时换水周期分别缩短至5.59、5.17 d。从连通性指数的变化来看,"引江济湖"和"两湖连通"增强了水系连通性,可提高水体自循环能力。更多还原

【Abstract】 The connection between rivers and lakes is an important measure to improve the aquatic environment, restore freshwater ecology and improve the living environment of human beings. However, the quantitative evaluation of the dynamic connectivity of the lake water system connectivity project in the city is few. Based on the plan of Bajiao-South Lake connecting project in Yueyang City of Human Province, the water from the Yangtze River to Bajiao Lake will be self-flowing to the South Lake through a newly excavated river channel in the Wangjiahe River Basin to improve water quality and aquatic ecological functions of Wangjiahe River and South Lake. The MIKE21 hydrodynamic model was used to simulate the 12 operating conditions at the minimum control water levels of 25.86 m and 26.06 m at the South Lake exit under the flow rates of 6 m~3/s, 12 m~3/s, and 24 m~3/s in flood season and non-flood season, respectively. The connectivity of the two lakes under water diversion conditions was analyzed and a quantitative evaluation index was proposed. The results showed that when the initial flow was 24 m~3/s and the minimum water level was 25.86 m, the connectivity between the flood season and the non-flood season reached the best state. The water exchange period was shortened to 5.59 d and 5.17 d, respectively. Judging from the changes in the connectivity index, the "leading to the lake" and the "two lakes connected" promoted water system connectivity and improved the ability of the water body to circulate.更多还原