南四湖是我国北方最大的淡水湖,地跨江苏和山东两省,自北向南由南阳、昭阳、独山、微山四湖相连而成,湖区面积1280平方千米,承接江苏、山东、河南、安徽四省的来水,是南水北调东线工程的必经之路和重要调蓄湖泊。南四湖经历了从陆地到洼地再从天然湖泊到水库型湖泊的历史演变,如今已作为生态环境的支撑,成为周边地区经济社会发展不可缺失的保障。 Nansi Lake is the largest freshwater lake in the north of our country. It stretches across Jiangsu and Shandong provinces. It is connected with Nanyang, Zhaoyang, Dushan and Weishan four lakes from north to south. The lake area covers an area of ​​1,280 square kilometers and takes over Jiangsu, Shandong The incoming water from four provinces of Henan and Anhui is the only route through which the East Route Project of South-to-North Water Diversion works and an important reservoir lake. Nansi Lake has undergone a historical evolution from land to depression and from natural lakes to reservoir lakes. Nowadays, Nansi Lake has become an indispensable guarantee for the economic and social development in the surrounding areas as the support of the ecological environment.