Poyang Lake - Hayoko

Located in the northern part of Jiangxi Province, China, this is the country's largest freshwater lake. Its area is 3,976 square kilometers. The lake surface is 21 meters above sea level. Its maximum depth is 23.7 meters. During the flood season, its area expands to 5,050 square kilometers. It is a gourd-shaped lake, wider in the south and narrower in the north. It was originally formed when water accumulated in a large basin formed during the Yanshan Movement, but due to the slow rise in most areas, especially on the southern shore, and the accumulation of silt from rivers, the lake's area is now less than half of what it was. Water from the Gan River, Xiu River, Po River, Fu River, Xin River, etc. flows into the lake, and then flows into the Yangtze River (Changjiang) via the lake's mouth in the north. In ancient times, it was called Pengze, Pengli, Penghu, etc., but in the Ming Dynasty, it came to be called Poyang Lake. Because the lake is slightly higher in altitude than the Yangtze, backflow from the Yangtze is not observed at normal water levels, and mud from various rivers is easily discharged, so the rate of sediment accumulation is slower than that of Dongting Lake. The lake shore is covered with fertile plains that stretch for thousands of miles, and it is well-connected by water and irrigation, making it a popular place for fish farming and lotus cultivation.

[Kono Michihiro]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

中国、江西省北部にある同国最大の淡水湖。面積3976平方キロメートル。湖面の標高21メートル。水深は最大23.7メートル。洪水期には面積は5050平方キロメートルに拡大する。南が広く北が狭いひょうたん形の湖である。元来は燕山(えんざん)運動の時期に形成された大盆地に水がたまったためできた湖だが、大部分の地域とくに南岸部の緩慢な上昇と河川の流し込む泥の堆積(たいせき)により、現在では湖の面積は半分以下になっている。贛水(かんすい)、修水、鄱江(はこう)、撫河(ぶが)、信江などの水が流入し、北方の湖口を経て長江(ちょうこう／チャンチヤン)（揚子江(ようすこう)）に流入する。古くは彭沢(ほうたく)、彭蠡(ほうれい)、彭湖(ほうこ)などと称していたが、明(みん)代になって鄱陽湖とよばれるようになった。標高が長江より少し高いので、正常な水位では長江からの逆流現象はみられず、各河川の泥をよく流出するので、洞庭(どうてい)湖に比べると土砂の埋積速度は遅い。湖岸は一望千里の沃野(よくや)をなし、水運と灌漑(かんがい)の便に恵まれ、養魚やハスの栽培も盛んである。

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