Water Area Variation and Response of River-lake Interactions in Poyang
Lake from 1977 to 2021
Lake has an essential role in Earth’s hydrologic cycle. The changing of
lake water areas shows the ecological health of lakes by instant
feedback. Remote sensing monitoring reflects the changes in lake water
intuitively. This study, based on remote sensing, combined with the
hydrological data, meteorological data, and land use survey,
investigated the Poyang lake water area changes from 1977 to 2021.
Examined the relationship between the lake water area and the impact
factor and analyzed the influence of river lake interaction on the lake
water area. The results showed that: (1) From 1977 to 2017, the water
area of Poyang Lake in flood season (June to September) and dry season
(November to Next February) showed a significant downward trend by
years. (2) In flood season, runoff, sediment, and precipitation
significantly correlate with a water area. In the dry season, sediment
significantly correlated with a water area. (3) The Three Gorges Dam
water impoundment at the upper reaches of the Yangtze River weakened and
eliminated the block and reverse flow of the Yangtze River on Poyang
lake, causing the water area to decrease in advance at the end of the
flood season after 2005, and decrease rapidly in the dry season after
2003. (4) The change in lakebed elevation caused by sedimentation and
human activities also accelerated the shrinkage of the water area.
Results demonstrated that the variation of river lake interaction is the
primary cause of the Poyang Lake water area’s dramatic change.