The Yangtze River case study application
The river basinThe Yangtze is Asia 's longest river with 6,300 km and about 700 tributaries. It flows from the Tibetan Plateau to the East China Sea. (see also: GIS/Mapserver)
It is heavily used for transportation, as a source of hydroelectric power and irrigation for agriculture.
The Yangtze River Basin covers an area of 1.9 million km² with a population of approximately 400 million, including China's major population and industrial centres, while its agricultural areas generate close to half the country's total crop production. The average rainfall (at Chikiang) is about 1,250 mm, runoff around 500 mm, specific sediment yield for the basin between 250 to 500 t/km²/y.
The Central Yangtze refers to the section of the river basin from Yichang in Hubei province
to Hukou in Jiangxi province. This is a region of floodplains and lakes and is one of the
Global 200 priority eco-regions for conservation.
River basin data
The Yangtze River (Chang-jiang in Chinese) is the largest river of China. It is about 6,300 km long, has total hydrographic catchment area of 1.8 million km2. Chang-jiang appropriately means "Long River". The Yangtze River begins in the in the Kunlun Mountains, Tibetan Plateau and is fed by snow and ice melt from the surrounding mountains, in the southwestern section of Qinghai Province in China, and flows generally south through Sichuan Province into Yunnan Province. In the vicinity of Huize the river bends sharply to the northeast. Thereafter, it flows generally northeast and east across central China through Sichuan, Hubei, Anhui, and Jiangsu Provinces to meet the East China Sea, about 23 km north of Shanghai.
There are over 400 sub-catchments larger than 1,000 km2 in Yangtze basin. 8 of these subcatchments exceed 80,000 km2, including: Yalong River, Mingjiang River, Jialing River, Wujiang River, Yuanjiang River, Xiangjiang River, Hanjiang River and Ganjiang River. There are also many lakes along the river, their total area is over 15,200 km². Most of thelakes are situated in the middle and lower reaches of Yangtze. Poyang Lake and Dongting Lake are the two largest freshwater lakes in China.
The Yangtze basin is located in the center of China, and it covers 19 provinces. With its numerous tributaries, the Yangtze river provides an important transportation network through the heart of some of the most densely populated and economically important areas in China. There are about 400 million people living in Yangtze river watershed.
Not so long ago, the major tasks of watersheds management in China were concentrated on flood control, water resources development and hydro power. Increasingly, water quality and environmental protection have to be taken into account, but flood control and water resources development are still high priorities. Most recently, the concepts of integrated watershed management for sustainable development have been adopted as the guiding policy principle.
This ecoregion of the central Yangtze basin mainly includes Dongting Lake, Poyang Lake, Jianghan Lakes, Anqing Lakes, and the mainstream and tributaries of Yangtze River. The total area accounts for 42% of the total Yangtze River Basin.
The Central Yangtze is affectionately known as China 's home of rice and fish in recognition of its fertile soils and the bounty of its rivers. In the rainy summer season the Yangtze River becomes swollen with the heavy rainfall in the upper Basin. The floodplain has a role in absorbing the overflow. In full flood the lakes merge with the river thereby reducing potential flood damage.
Despite centuries of change, the lakes and floodplains of the Central Yangtze continue to support a wealth of distinctive natural diversity. The flora and fauna of this area are uniquely adapted to the seasonal changes in the water cycle - fish move freely between them while non-aquatic animals make for higher ground.
Chang-jiang Water Resources Commission (CWRC) is one of the Seven Watershed Management organizations in China, directly under the MInistry. The Commission is located in Wuhan, Hubei province, and is responsible for the Yangtze river watershed and the southwest river valleys of China. It is authorized by the State to exercise administrative water management in its region: to provide overall management of water resources in the valley in accordance with the Water Law of the People's Republic of China; to take charge of the comprehensive, planning, harnessing, development, management and protection of the water resources in the entire valley; to give instructions to conduct examination, coordination and supervision on, and to perform services for the regional water resources facilities.
also located in the Yangtze River basin is the Nanjing Hydraulic Research Institute (Nanjing, Jiangsu province) which is also a famous research institute in the water sector, but not institutionally under the CWRC.