Analysis on inflow and outflow of water resources zones around Taihu Lake and its contribution

Based on the data of inflow and outflow, precipitation, and water diversion of Taihu Lake from 1986 to 2018, the TFPW-MK trend test method and other statistical methods were used to analyze the variation characteristics of inflow and outflow water volume of water resources zones around the Taihu Lake and the water exchange period of Taihu Lake. The influence factors of significant changes of annual inflow water volume of Huxi Zone and annual outflow water volume of Wangyu River and Taipu River were discussed. The results show that the annual water inflow and outflow, net water inflow and the annual water inflow and outflow of each water resources zone and its proportion show different trends. The interannual variations of the annual inflow and outflow water volume and proportion of inflow of Wangyu River and proportion of outflow of Huxi Zone are the most significant. The average annual inflow and proportion of the Huxi Zone was the largest in the water resources zones in different decades, and the average annual outflow and its proportion of Taipu River after 1980 s was the largest. Huxi Zone has the largest contribution rate to the growth of water inflow, and Zhexi Zone has the largest contribution rate to the growth of water outflow. Rainfall has great influence on the interannual fluctuation of inflow water volume of Huxi Zone and outflow water volume of Wangyu River and Taipu River. The average water exchange period of Taihu Lake showed a decreasing trend, which decreased from 200 d in 1980 s to 154 d in 2010 s. © 2021, Editorial Board of Water Resources Protection. All rights reserved.