The Yangtze River, or Chang Jiang is the longest river in Asia, and the third-longest in the world. It flows for 6,300 kilometres (3,915 mi) from the glaciers on the Tibetan Plateau in Qinghai eastward across southwest, central and eastern China before emptying into the East China Sea at Shanghai. It is also one of the biggest rivers by discharge volume in the world. The Yangtze drains one-fifth of China’s land area and its river basin is home to one-third of China’s population. Along with the Yellow River, the Yangtze is the most important river in the history, culture and economy of China. The prosperous Yangtze River Delta generates as much as 20% of China’s GDP.
The river is an important physical and cultural dividing line between North and South China. Chinese living north of the Yangtze speaks varying dialects of Mandarin. Most of the provinces south of the river have native Sinitic languages that are unintelligible to Mandarin-speakers. The Yangtze River flows through a diverse array of ecosystems and is itself habitat to several endemic and endangered species including the Yangtze River dolphin, Chinese alligator, and the Yangtze sturgeon.
For thousands of years, man has used the river for water, irrigation, sanitation, transportation, industry, boundary marking and war. The Three Gorges Dam on the Yangtze River is the largest hydro-electric power station in the world. In recent years, the river has suffered from industrial pollution, agricultural run-off, siltation, and loss of wetland and lakes, which exacerbates seasonal flooding. Some sections of the river are now protected as nature reserves. A stretch of the Yangtze flowing through deep gorges in western Yunnan is part of the Three Parallel Rivers of Yunnan Protected Areas, a UNESCO World Heritage Site.
The Yangtze River is important to the cultural origins of southern China. Human activity was found in the Three Gorges area as far back as 27 thousand years ago, initiating debate over the origin of the Chinese people. In the Spring and Autumn Period, Ba and Shu were located along the western part of the river, covering modern Sichuan, Chongqing, and western Hubei; Chu was located along the central part of river, corresponding to Hubei, Hunan, Jiangxi, and southern Anhui. Wu and Yue were located along the eastern part of the river, now Jiangsu, Zhejiang, and Shanghai. Although the Yellow River region was richer and more developed at that time, the milder climate and more peaceful environment made the Yangtze River area more suitable for agriculture. From the Han Dynasty, the region of the Yangtze River became more and more important to China’s economy. The establishment of irrigation systems (the most famous one is Dujiangyan, northwest of Chengdu, built during the Warring States period) made agriculture very stable and productive.
By the Song dynasty, the area along the Yangtze had become among the most wealthiest and developed parts of the country, especially in the lower reaches of the river. Early in the Qing dynasty, the region called Jiangnan (that includes the southern part of Jiangsu, the northern part of Zhejiang, and the southeastern part of Anhui) provided 1/3-1/2 of the nation’s revenues. The Yangtze has long been the backbone of China’s inland water transportation system, which remained particularly important for almost two thousand years, until the construction of the national railway network during the 20th century. The Grand Canal connects the lower Yangtze with the major cities of the Jiangnan region south of the river (Wuxi, Suzhou, Hangzhou) and with northern China (all the way to Beijing).
The less well known ancient Lingqu Canal, connecting the upper Xiang River with the headwaters of the Guijiang, allowed a direct water connection from the Yangtze Basin to the Pearl River Delta. Historically, the Yangtze became the political boundary between north China and south China several times (see History of China) because of the difficulty of crossing the river. This occurred notably during the Southern and Northern Dynasties, and the Southern Song.
Many battles took place along the river, the most famous being the Battle of Red Cliffs in 208 AD during the Three Kingdoms period. Politically, Nanjing was the capital of China several times, although most of the time its territory only covered the southeastern part of China, such as the Wu kingdom in the Three Kingdoms period, the Eastern Jin Dynasty, and during the Southern and Northern Dynasties and Five Dynasties and Ten Kingdoms periods. Only the Ming occupied most parts of China from their capital at Nanjing, though it later moved the capital to Beijing. The ROC capital was located in Nanjing in the periods 1911-1912, 1927–1937, and 1945-1949.