How was Hongze Lake formed?

There are three major factors in the formation of Hongze Lake.

1. The depression formed by crustal fracture is a natural factor for the formation of Hongze Lake, and the embryo began in the small lake before Tang and Song Dynasties. There are mainly Fuling Lake, Pofu Creek, Mudun Lake and Wanjia Lake.

2. The Yellow River's capture of Huai River is an objective factor to form the embryonic form of Hongze Lake. In the fifth year of the Song Dynasty (A.D. 1 194), the Yellow River decided to take it, and it was divided into north and south branches on the Liangshanpo. The south branch joins Surabaya and flows southward into the Huaihe River, which is the beginning of the diversion of the Yellow River.

In the fifth year of Xianfeng in the Qing Dynasty (AD 1855), the Yellow River moved north and entered the sea from Lijin. The Yellow River occupied the Huaihe River for nearly 700 years. Because the Yellow River is condescending, it flows into the Huaihe River, where Huanghuai meets, the flow increases and the water level rises, connecting small lakes and depressions such as Fuling Lake and Broken Kettle Pond into a lake.

3. Building a high weir (Hongze Lake levee) is a man-made factor and a decisive factor for the complete formation of Hongze Lake.

Extended data:

According to the History of Huaihe River, about 3 million years ago, Hongze Lake was originally a part of the Yellow Bay, where the lower reaches of the ancient Huaihe River passed. Because a large amount of sediment carried by the Yangtze River, the Yellow River and the Huaihe River are deposited in their respective estuaries, they accumulate into estuarine deltas, and then gradually develop and expand, forming a delta plain that continues to extend to the ocean, and the coastline gradually advances from land to the ocean.

At the same time, the sediment carried by the current accumulates in the bay area along the delta impact plain. In this way, the impact and accumulation year after year finally isolated this shallow bay from the sea and closed it into a lagoon. This is the embryonic form of Hongze Lake. Hongze Lake was originally composed of several small lakes, such as Broken Kettle Pond, Baishuitan, Fuling Lake, Mudun Lake and Wanjia Lake, with a small scope.

With the passage of time, ancient working people built dams and weirs on several small lakes, such as Pofutang and Baishuitang, reclaimed lakes for farmland, and opened canals to divert water for irrigation. In addition, from 1 194 to 1855, the Yellow River captured the Huaihe River for more than 660 years, and the original lake area was expanded year by year due to long-term floods and war damage.

In the 19th year of Emperor Kangxi of Qing Dynasty (1680), heavy rain continued for 70 days in Huanghuai area, and the water in Huanghuai area rose. After the ancient Sizhou city was flooded by Hongze Lake, a vast Hongze Lake with an area of 2069 square kilometers was formed today.

Baidu Encyclopedia-Hongze Lake