Rice field. Poyang Lake area, Jiangxi Province, China, in May 2018.
Source – Evgeniya Soldatova, CC SA 4.0.
With China’s largest freshwater lake drying up, work crews dig trenches to keep water flowing to the rice crops.
Poyang Lake, located in Jiujiang, is the largest freshwater lake in China. The lake is fed by the Gan, Xin, and Xiu rivers, which connect to the Yangtze through a channel.
The lake’s depth can vary between the wet and dry seasons, but in recent years the size of the lake has been decreasing overall. In a normal year, the area of the lake averages 3,500 square kilometers (1,400 sq mi).
However, in early 2012, due to drought, sand quarrying, and the practice of storing water at the Three Gorges Dam the area of the lake reached a low of about 200 square kilometers (77 sq mi).
Needless to say, Poyang Lake has seen a dramatic decline in water levels this year, with it being reduced to just 25 percent of its normal size. Because of the decreased water level, channels normally used to bring water to crops in the landlocked southeastern province of Jiangxi have been cut off.
Work crews have been using excavators to dig trenches to bring water to rice fields and other crops. The crews are having to wait until after dark because it is so hot during the day, according to CTV News Canada.
The severe heat wave is wreaking havoc across much of southern China. High temperatures have sparked mountain fires that have forced the evacuation of 1,500 people in the southwest, and factories have been ordered to cut production as hydroelectric plants reduce their output amid drought conditions.
The extreme heat and drought have wilted crops and shrunk rivers including the giant Yangtze, disrupting cargo traffic.
A lake with multiple uses
Besides being a vital water supply for agriculture, Poyang Lake provides a habitat for half a million migratory birds and is a favorite destination for birding. During the winter, the lake becomes home to many migrating Siberian cranes (Leucogeranus leucogeranus), up to 90 percent of which spend the winter there.
A fishing ban has been in place since 2002. In January 2020, China imposed a 10-year fishing moratorium on 332 sites along the Yangtze, including Poyang Lake to protect marine biodiversity.
The Three Gorges Dam while helping to control flooding, can now cause Poyang Lake to dry up. The Jiangxi local government has proposed to build the Poyang Lake Dam to maintain water levels in the lake, building a sluice wall across the connection between the lake and the Yangtze river.
There is a lot of criticism over the dam. An environmental impact assessment is pending. Scientists, as well as environmental groups such as the World Wide Fund for Nature, have criticized the proposal, arguing that artificially engineering water levels in the lake will adversely affect wildlife diversity.
Poyang Lake used to welcome its wet season from April to August, yet the extreme weather this year not only caused the lake to enter the earliest dry season in 71 years, but satellite images also show an alarming sign of the tidal-flat presenting tree-shape landscapes in certain sections of Poyang Lake.