NANCHANG - China's largest freshwater lake, Poyang, has shrunk by one third in the past three days due to reduced water supply from the Yangtze River and little rainfall.

At 8 am Wednesday, the lake's surface area was 1,490 sq km, a reduction of 679 sq km compared with 2,169 sq km on Monday, said the Jiangxi Provincial Hydrological Bureau.

The water level at Xingzi hydrological station was 11.99 meters at 4 pm Wednesday, 2.13 meters lower than the levels in normal years. The water level is falling by 30 cm per day.

Reduced water supply from the upper Yangtze River due to dams and little rainfall in the past month in Jiangxi were two major causes for the shrinking, said the bureau.

The average precipitation was less than 5 mm since Sept 20 in Jiangxi province.

The lake's flood season began on April 30 and lasted until Oct 18. The flood period was 33 days longer than that of last year.

The sharp fall of water levels in the lake will affect shipping and fishing as well as the water supply for nearby residents.