Abstract:

Satellite-based observation provides an effective way to track water variations, since it can be used to retrieve many major hydro-physical variables, especially the water surface area. Here we used multi-satellite data to explore three-decade surface area variations of Poyang Lake, the largest freshwater lake in China. Our results revealed that the water area had declined generally in the last three decades. There existed a downtrend period of about 10 years. Generally, the decreasing trend of the decline was found to be significantly related to basin-scale climate change. Furthermore, the seasonal data demonstrated the remarkable change in surface area from over 3000 km(2) in summer to less than 1000 km(2) in winter. In the period examined, the lake surface area shrank to minimum values in 2003 and 2006. This was possibly related to land-use and land-cover change and construction of reservoirs in the basin, in addition to local climate change.