Kyrgyz mosque in the Pamirs, western Uygur Autonomous Region of Xinjiang, China.Dugald Bremner/Stone
The second step lies to the north of the Kunlun and Qilian mountains and (farther south) to the east of the Qionglai and Daliang ranges. There the mountains descend sharply to heights of between 6,000 and 3,000 feet (1,800 and 900 metres), after which basins intermingle with plateaus. This step includes the Mongolian Plateau, the Tarim Basin, the Loess Plateau (loess is a yellow-gray dust deposited by the wind), the Sichuan Basin, and the Yunnan-Guizhou (Yungui) Plateau.
The third step extends from the east of the Dalou, Taihang, and Wu mountain ranges and from the eastern perimeter of the Yunnan-Guizhou Plateau to the China Sea. Almost all of this area is made up of hills and plains lying below 1,500 feet (450 metres).
The most remarkable feature of China’s relief is the vast extent of its mountain chains; the mountains, indeed, have exerted a tremendous influence on the country’s political, economic, and cultural development. By rough estimate, about one-third of the total area of China consists of mountains. China has the world’s tallest mountain and the world’s highest and largest plateau, in addition to possessing extensive coastal plains. The five major landforms—mountain, plateau, hill, plain, and basin—are all well represented. China’s complex natural environment and rich natural resources are closely connected with the varied nature of its relief.
The topography of China is marked by many splendours. Mount Everest (Qomolangma Feng), situated on the border between China and Nepal, is the highest peak in the world, at an elevation of 29,035 feet (8,850 metres; see Researcher’s Note: Height of Mount Everest). By contrast, the lowest part of the Turfan Depression in the Uygur Autonomous Region of Xinjiang—Lake Ayding—is 508 feet (155 metres) below sea level. The coast of China contrasts greatly between South and North. To the south of the bay of Hangzhou, the coast is rocky and indented with many harbours and offshore islands. To the north, except along the Shandong and Liaodong peninsulas, the coast is sandy and flat.
China is prone to intense seismic activity throughout much of the country. The main source of this geologic instability is the result of the constant northward movement of the Indian tectonic plate beneath southern Asia, which has thrust up the towering mountains and high plateaus of the Chinese southwest. Throughout its history China has experienced hundreds of massive earthquakes that collectively have killed millions of people. Two in the 20th century alone—in eastern Gansu province (1920) and in the city of Tangshan, eastern Hebei province (1976)—caused some 250,000 deaths each, and a quake in east-central Sichuan province in 2008 killed tens of thousands and devastated a wide area.
China’s physical relief has dictated its development in many respects. The civilization of Han Chinese originated in the southern part of the Loess Plateau, and from there it extended outward until it encountered the combined barriers of relief and climate. The long, protruding corridor, commonly known as the Gansu, or Hexi, Corridor, illustrates this fact. South of the corridor is the Plateau of Tibet, which was too high and too cold for the Chinese to gain a foothold. North of the corridor is the Gobi Desert, which also formed a barrier. Consequently, Chinese civilization was forced to spread along the corridor, where melting snow and ice in the Qilian Mountains provided water for oasis farming. The westward extremities of the corridor became the meeting place of the ancient East and West.
Thus, for a long time the ancient political centre of China was located along the lower reaches of the Huang He (Yellow River). Because of topographical barriers, however, it was difficult for the central government to gain complete control over the entire country, except when an unusually strong dynasty was in power. In many instances the Sichuan Basin—an isolated region in southwestern China, about twice the size of Scotland, that is well protected by high mountains and is self-sufficient in agricultural products—became an independent kingdom. A comparable situation often arose in the Tarim Basin in the northwest. Linked to the rest of China only by the Gansu Corridor, this basin is even remoter than the Sichuan, and, when the central government was unable to exert its influence, oasis states were established; only the three strong dynasties—the Han (206 bc–ad 220), the Tang (ad 618–907), and the Qing, or Manchu (1644–1911/12)—were capable of controlling the region.
Apart from the three elevation zones already mentioned, it is possible—on the basis of geologic structure, climatic conditions, and differences in geomorphologic development—to divide China into three major topographic regions: the eastern, northwestern, and southwestern zones. The eastern zone is shaped by the rivers, which have eroded landforms in some parts and have deposited alluvial plains in others; its climate is monsoonal (characterized by seasonal rain-bearing winds). The northwestern region is arid and eroded by the wind; it forms an inland drainage basin. The southwest is a cold, lofty, and mountainous region containing intermontane plateaus and inland lakes.
The three basic regions may be further subdivided into second-order geographic divisions. The eastern region contains 10 of these, the southwest contains two, and the northwest contains three. Below is a brief description of each division.
The eastern region
The Northeast Plain
The Northeast Plain (also known as the Manchurian Plain and the Sung-liao Plain) is located in China’s Northeast, the region formerly known as Manchuria. It is bordered to the west and north by the Da Hinggan (Greater Khingan) Range and to the east by the Xiao Hinggan (Lesser Khingan) Range. An undulating plain split into northern and southern halves by a low divide rising from 500 to 850 feet (150 to 260 metres), it is drained in its northern part by the Sungari River and tributaries and in its southern part by the Liao River. Most of the area has an erosional rather than a depositional surface, but it is covered with a deep soil. The plain has an area of about 135,000 square miles (350,000 square km). Its basic landscapes are forest-steppe, steppe, meadow-steppe, and cultivated land; its soils are rich and black, and it is a famous agricultural region. The river valleys are wide and flat with a series of terraces formed by deposits of silt. During the flood season the rivers inundate extensive areas.
Da Hinggan (Greater Khingan) Range, southeast of Hailar, Inner Mongolia Autonomous Region, China.Richard Harrington/Comstock
The Changbai Mountains
To the southeast of the Northeast Plain is a series of ranges comprising the Changbai, Zhangguangcai, and Wanda mountains, which in Chinese are collectively known as the Changbai Shan, or “Forever White Mountains”; broken by occasional open valleys, they reach elevations mostly between 1,500 and 3,000 feet (450 and 900 metres). In some parts the scenery is characterized by rugged peaks and precipitous cliffs. The highest peak is the volcanic cone of Mount Baitou (9,003 feet [2,744 metres]), which has a beautiful crater lake at its snow-covered summit. As one of the major forest areas of China, the region is the source of many valuable furs and famous medicinal herbs. Cultivation is generally limited to the valley floors.
The North China Plain
Comparable in size to the Northeast Plain, most of the North China Plain lies at elevations below 160 feet (50 metres), and the relief is monotonously flat. It was formed by enormous sedimentary deposits brought down by the Huang He and Huai River from the Loess Plateau; the Quaternary deposits alone (i.e., those from the past 2.6 million years) reach thicknesses of 2,500 to 3,000 feet (760 to 900 metres). The river channels, which are higher than the surrounding locality, form local water divides, and the areas between the channels are depressions in which lakes and swamps are found. In particularly low and flat areas, the underground water table often fluctuates from 5 to 6.5 feet (1.5 to 2 metres), forming meadow swamps and, in some places, resulting in saline soils. A densely populated area that has long been under settlement, the North China Plain has the highest proportion of land under cultivation of any region in China.