The Yangtze River, or Chang Jiang, is the longest river in China and Asia, and the third-longest in the world. The river is about 6,300 kilometres (3,915 mi) and flows from its source in Qinghai Province, eastwards into the East China Sea at Shanghai. It acts as a dividing line between North and South China, although geographers generally consider the Qinling-Huai River line to be the official line of geographical division. As the largest river in the region, the Yangtze is historically, culturally, and economically important to China. One of the dams on the river, the Three Gorges Dam, is the largest hydro-electric power station in the world. The section of the river flowing through deep gorges in Yunnan province is part of the Three Parallel Rivers of Yunnan Protected Areas: a UNESCO World Heritage Site.

The name Yangtze River, as well as other similar names such as Yangtse River, Yangzi River and Yangtze Kiang, is derived from Yangzi Jiang listen. The name supposedly comes from the ancient ferry crossing Yangzi Jin. Because it was the name first heard by missionaries and traders, this name was applied in English to the whole river. The modern Chinese name, Chang Jiang, literally means "Long River". (Jiang is the classical Chinese for river.) and may sometimes also be used in English. It is also known to many as the 'Main Street' of China.

Like many rivers, the river is known by different names over its course. At its source, it is called in Chinese the Dangqu. Downstream, it is called the Tuotuo River and then the Tongtian River. Where it runs through deep gorges parallel to the Mekong and the Salween before emerging onto the plains of Sichuan, it is known as the Jinsha River. The Three Gorges Dam on the river is the largest dam in the world.

The Yangtze was earlier known to the Chinese as simply Jiang, which has become a generic name meaning "river", or the Da Jiang. The Tibetan name for the river is Drichu. The Yangtze is sometimes referred to as the Golden Waterway.

Geography

The river originates in a glacier lying on the west of Geladandong Mountain in the Dangla Mountain Range on the eastern part of the Tibetan plateau. It runs eastward through Qinghai, turning southward down a deep valley at the border of Sichuan and Tibet to reach Yunnan. In the course of this valley, the river's elevation drops from above 5000 m to less than 1000 m. The headwaters of the Yangtze are situated at an elevation of about 4,900 m (16,100 ft). In its descent to sea level, the river falls to an altitude of 305 m (1,001 ft) at Yibin, Sichuan Province, the head of navigation for riverboats, and to 192 m (630 ft) at Chongqing. Between Chongqing and Yichang (I-ch'ang), at an altitude of 40 m (130 ft) and a distance of about 320 km (200 mi), it passes through the spectacular Yangtze Gorges, which are noted for their natural beauty but are dangerous to shipping.

It enters the basin of Sichuan at Yibin. While in the Sichuan basin, it receives several mighty tributaries, increasing its water volume significantly. It then cuts through Mount Wushan bordering Chongqing and Hubei to create the famous Three Gorges. Eastward of the Three Gorges, Yichang is the first city on the Yangtze Plain.

After entering Hubei, the Yangtze receives more water from thousands of lakes. The largest of these lakes is Dongting Lake, which is located on the border of Hunan and Hubei provinces, and is the outlet for most of the rivers in Hunan. At Wuhan, it receives its biggest tributary, the Han River, bringing water from its northern basin as far as Shaanxi.

At the northern tip of Jiangxi, Lake Poyang, the biggest freshwater lake in China, merges into the river. The river then runs through Anhui and Jiangsu provinces, receiving more water from innumerable smaller lakes and rivers, and finally reaches the East China Sea at Shanghai.

Four of China's five main freshwater lakes contribute their waters to the Yangtze River. Traditionally, the upstream part of the Yangtze River refers to the section from Yibin to Yichang; the middle part refers to the section from Yichang to Hukou County, where Lake Poyang meets the river; the downstream part is from Hukou to Shanghai. It is home to many thousands of people.

Characteristics

The Yangtze flows into the East China Sea and was navigable by ocean-going vessels up a thousand miles from its mouth even before the Three Gorges Dam was built. As of June 2003, this dam spans the river, flooding Fengjie, the first of a number of towns affected by the massive flood control and power generation project. This is the largest comprehensive irrigation project in the world and has a significant impact on China's agriculture. Its proponents argue that it will free people living along the river from floods that have repeatedly threatened them in the past and will offer them electricity and water transport—though at the expense of permanently flooding many existing towns (including numerous ancient cultural relics) and causing large-scale changes in the local ecology.

Opponents of the dam point out that there are three different kinds of floods on the Yangtze River: floods which originate in the upper reaches, floods which originate in the lower reaches, and floods along the entire length of the river. They argue that the Three Gorges dam will actually make flooding in the upper reaches worse and have little or no impact on floods which originate in the lower reaches. Twelve hundred years of low water marks on the river were recorded in the inscriptions and the carvings of carp at Baiheliang, now submerged.

The Yangtze is flanked with metallurgical, power, chemical, auto, building materials and machinery industrial belts and high-tech development zones. It is playing an increasingly crucial role in the river valley's economic growth and has become a vital link for international shipping to the inland provinces. The river is a major transportation artery for China, connecting the interior with the coast.

The river is one of the world's busiest waterways. Traffic includes commercial traffic transporting bulk goods such as coal as well as manufactured goods and passengers. Cargo transportation reached 795 million tons in 2005. River cruises several days long, especially through the beautiful and scenic Three Gorges area, are becoming popular as the tourism industry grows in China.

Flooding along the river has been a major problem. The rainy season in China is May and June in areas south of Yangtze River, and July and August in areas north of it. The huge river system receives water from both southern and northern flanks, which causes its flood season to extend from May to August. Meanwhile, the relatively dense population and rich cities along the river make the floods more deadly and costly. The most recent major floods were the 1998 Yangtze River Floods, but more disastrous were the 1954 Yangtze River Floods, killing around 30,000 people. Other severe floods included those of 1911, which killed around 100,000, 1931 (145,000 dead), and 1935 (142,000 dead).

The Yangtze is very polluted, especially in Hubei (Shashi District).

History

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.

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