Yangtze River - Geography

Geography

The river originates from several tributaries, two of which have claims to be the source. The Chinese government has recognized the source of the Tuotuo tributary at the base of a glacier lying on the west of Geladandong Mountain in the Dangla Mountain Range on the eastern part of the Qinghai-Tibet Plateau. However, the geographical source (i.e., longest river distance from the sea) lies in wetlands at 32°36′14″N 94°30′44″E / 32.60389°N 94.51222°E / 32.60389; 94.51222 and 5,170 m (16,960 ft) above sea level at the head of the Dan Qu tributary. These tributaries join and the river then 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 5,000 m (16,000 ft) to less than 1,000 m (3,300 ft). 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, 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.

The origin of the Yangtze River is dated to about 45 million years ago in the Eocene, but many people do not accept this point.