Abstract:Lake is an important factor to maintain ecological balance. As the largest freshwater lake in China, water area of Poyang Lake has been changed due to the advance and prolonged dry season. It is of great significance for the stability of regional ecological environment and economic development to study the variation characteristics and driving factors of water area in Poyang Lake during the dry season. In this study, based on the remote sensing image data of Poyang Lake in dry season from 1973 to 2018, Mann-Kendall trend test, Mann-Kendall mutation analysis and Pettitt mutation test were used to analyze the area change of Poyang Lake during the dry season, and the double mass curve method was used to quantify the effects of the difference of inflow and outflow as well as land use change caused by human activities on the water area of Poyang Lake. The results showed that:(1) During the study period, the water area of Poyang Lake showed a very significant decline in the dry season (P<0.01), the year of the abrupt transition point was 2002 (P<0.01). (2) The difference of runoff in and out of the lake showed an insignificant increase trend over the years. From 1980 to 2015, the land use of Poyang Lake basin showed an increase in industrial and construction land in urban and rural areas, while other land use types showed a decreasing trend. (3) Taking 1977 to 2002 as the base period, the contribution rate of land use change caused by human activities was 87.48% to the change of Poyang Lake's water area during the dry season from 2003 to 2016, which was the main reason for the significant reduction of water area of Poyang Lake in dry season. The results could provide scientific basis for the rational utilization of water resources and the maintenance of regional ecosystem balance in Poyang Lake.