Top rivers of China: 1. The Yangzi (Changjiang or Yangtze River) , 2. the Huanghe (Yellow River), 3. The Heilongjiang (Heilong River, Amur) in northeast China. 4. Zhujiang (Pearl River) in Guangdong. Other major rivers are the Liaohe River and Songhua River in the northeast, Huai River in the north, and Lancang River (Mekong) in the southwest, and Yarlung Tsangpo River in Tibet.
China has 50,000 rivers totaling some 420,000 kilometers in length and each having a catchment area of more than 100 square kilometers. The Yangzi has a catchment area of 1.8 million square kilometers and is the third longest river in the world after the Amazon and the Nile.
China has 50,000 rivers totaling some 420,000 kilometers in length and each having a catchment area of more than 100 square kilometers. Some 1,500 of these rivers each have catchment areas exceeding 1,000 square kilometers. Most rivers flow from west to east and empty into the Pacific Ocean. The Yangzi (Changjiang or Yangtze River), which rises in Tibet, flows through Central China, and, having traveled 6,300 kilometers, enters the Yellow Sea near Shanghai. The Yangzi has a catchment area of 1.8 million square kilometers and is the third longest river in the world after the Amazon and the Nile. The second longest river in China is the Huanghe (Yellow River), which also rises in Tibet and travels circuitously for 5,464 kilometers through North China before reaching the Bo Hai Gulf on the north coast of Shandong Province. It has a catchment area of 752,000 square kilometers. The Heilongjiang (Heilong or Black Dragon River) flows for 3,101 kilometers in Northeast China and an additional 1,249 in Russia, where it is known as the Amur. The longest river in South China is the Zhujiang (Pearl River), which is 2,214 kilometers long. Along with its three tributaries, the Xi, Dong, and Bei—West, East, and North—rivers, it forms the rich Pearl River Delta near Guangzhou, Zhuhai, Macau, and Hong Kong. Other major rivers are the Liaohe in the northeast, Haihe in the north, Qiantang in the east, and Lancang in the southwest.
Because the river level drops precipitously toward the North China Plain, where it continues a sluggish course across the delta, it transports a heavy load of sand and mud from the upper reaches, much of which is deposited on the flat plain. The flow is channeled mainly by constantly repaired manmade embankments; as a result the river flows on a raised ridge fifty meters or more above the plain, and waterlogging, floods, and course changes have recurred over the centuries. Traditionally, rulers were judged by their concern for or indifference to preservation of the embankments. In the modern era, China has undertaken extensive flood control and conservation measures.
Flowing from its source in the Qingzang highlands, the Yellow River courses toward the sea through the North China Plain, the historic center of Chinese expansion and influence. Han Chinese people have farmed the rich alluvial soils of the plain since ancient times, constructing the Grand Canal for north-south transport (see History of China - Imperial era). The plain itself is actually a continuation of the Dongbei (Manchurian) Plain to the northeast but is separated from it by the Bohai Gulf, an extension of the Yellow Sea.
Like other densely populated areas of China, the plain is subject not only to floods but to earthquakes. For example, the mining and industrial center of Tangshan, about 165 km east of Beijing, was leveled by an earthquake in July 1976 that was believed to be the largest earthquake of the 20th century by death toll.
The Qinling Mountains, a continuation of the Kunlun Mountains, divides the North China Plain from the Yangtze River Delta and is the major physiographic boundary between the two great parts of China Proper. It is in a sense a cultural boundary as well, influencing the distribution of custom and language. South of the Qinling mountain range divide are the densely populated and highly developed areas of the lower and middle plains of the Yangtze River and, on its upper reaches, the Sichuan Basin, an area encircled by a high barrier of mountain ranges.
The country's longest and most important waterway, the Yangtze River is navigable over much of its length and has a vast hydroelectric potential. Rising on the Qingzang Plateau, the Yangtze River traverses 6,300 km through the heart of the country, draining an area of 1.8 million km² before emptying into the East China Sea. The roughly 300 million people who live along its middle and lower reaches cultivate a great rice- and wheat-producing area. The Sichuan Basin, favored by a mild, humid climate and a long growing season, produces a rich variety of crops; it is also a leading silk-producing area and an important industrial region with substantial mineral resources.
Second only to the Qinling range as an internal boundary is the Nanling, the southernmost of the east-west mountain ranges. The Nanling overlooks the part of China where a tropical climate permits two crops of rice to be grown each year. Southeast of the mountains lies a coastal, hilly region of small deltas and narrow valley plains; the drainage area of the Pearl River and its associated network of rivers occupies much of the region to the south. West of the Nanling, the Yunnan-Guizhou Plateau rises in two steps, averaging 1,200 and 1,800 m in elevation, respectively, toward the precipitous mountain regions of the eastern Qingzang Plateau.
The Hai River, like the Pearl River and other major waterways, flows from west to east. Its upper course consists of five rivers that converge near Tianjin, then flow seventy kilometers before emptying into the Bohai Gulf. Another major river, the Huai River, rises in Henan Province and flows through several lakes before joining the Pearl River near Yangzhou.
Inland drainage involving a number of upland basins in the north and northeast accounts for about 40 percent of the country's total drainage area. Many rivers and streams flow into lakes or diminish in the desert. Some are useful for irrigation.
China's extensive territorial waters are principally marginal seas of the western Pacific Ocean; these waters wash the shores of a long and much-indented coastline and approximately 5,000 islands. The Yellow Sea, East China Sea, and South China Sea, too, are marginal seas of the Pacific Ocean. More than half the coastline (predominantly in the south) is rocky; most of the remainder is sandy. The Bay of Hangzhou roughly divides the two kinds of shoreline.