Dynamic Monitoring of the Lake Area in the Middle and Lower Reaches of the Yangtze River Using MODIS Images Between 2000 and 2016

The middle and lower reaches of the Yangtze river are an important component of the Yangtze River Economic Zone that is a center of immense biological wealth, apart from its social and economic importance in China. As the main supply of water sources, a complete understanding of the change in the lake area is essential for the development of the Yangtze River Economic Zone. In this paper, we collected Moderate Resolution Imaging Spectroradiometer medium resolution (500 m) data from 2000 to 2016 to examine the long-term variation of the four largest lakes in this area, Poyang Lake, Dongting Lake, Taihu Lake, and Chaohu Lake. Taihu Lake and Chaohu Lake have a relatively stable lake area. Because they are clearly affected by human activities, the inflow and outflow of water from these two lakes are almost the same. In contrast, Poyang Lake and Dongting Lake experience rapid and large short-term fluctuations in the water area. These two lakes with large drainage areas have high amounts of water flowing into and out of them. The area of Poyang Lake and Dongting Lake showed a downward trend before 2010. However, we found the annual minimum area of the two lakes increased by 60.51 km ² /year (Poyang Lake) and 51.64 km ² /year (Dongting Lake) after 2010. The timely and proper monitoring in this study is of major significance for protecting these lakes.