Fig.7 Characteristics of sediment in Poyang Lake estuary during
1980-2020
4.2.3
Changes of Evaporation and Precipitation in Poyang Lake.
From 1977 to 2020, the evaporation of the dry season has an
insignificant increasing trend (Z=0.56). Evaporation of flood season has
a significant downward trend (Z=-2.14), declining rate being4.62
*10-1mm/a, and change point at 1992. The Pearson
analysis test result shows that evaporation and lake area has no
significant correlativity. In the dry season, the correlation
coefficient is 0.11. In the flood season, the correlation coefficient is
0.06. (Figure 8)
In Figure 9, from 1977 to 2020, flood season precipitation had an
insignificant downward trend (Z=-0.41), and dry season precipitation
significantly increased (Z=2.48). The correlation coefficient of flood
season precipitation and area is 0.31, at a 99% confidence level. In
the dry season, the correlation coefficient is insignificant.