- The Han dynasty
- The early republican period
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 meters), 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.
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 meters). 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 meters]), 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 meters), 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 meters). 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 meters), 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.
The Loess Plateau
This vast plateau of some 154,000 square miles (400,000 square km) forms a unique region of loess-clad hills and barren mountains between the North China Plain and the deserts of the west. In the north the Great Wall of China forms the boundary, while the southern limit is the Qin Mountains in Shaanxi province. The average surface elevation is roughly 4,000 feet (1,200 meters), but individual ranges of bedrock are higher, reaching 9,825 feet (2,995 meters) in the Liupan Mountains. Most of the plateau is covered with loess to thicknesses of 165 to 260 feet (50 to 80 meters). In northern Shaanxi and eastern Gansu provinces, the loess may reach much greater thicknesses. The loess is particularly susceptible to erosion by water, and ravines and gorges crisscross the plateau. It has been estimated that ravines cover approximately half the entire region, with erosion reaching depths of 300 to 650 feet (90 to 200 meters).
The Shandong Hills
These hills are basically composed of extremely ancient crystalline shales and granites of early Precambrian age (i.e., older than about 2.5 billion years) and of somewhat younger sedimentary rocks dating to about 540–420 million years ago. Faults have played a major role in creating the present relief, and, as a result, many hills are horsts (blocks of the Earth’s crust uplifted along faults), while the valleys have been formed by grabens (blocks of the Earth’s crust that have been thrust down along faults). The Jiaolai Plain divides this region into two parts. The eastern part is lower, lying at elevations averaging below 1,500 feet (450 meters), with only certain peaks and ridges rising to 2,500 feet and (rarely) to 3,000 feet (900 meters); the highest point, Mount Lao, reaches 3,714 feet (1,132 meters). The western part is slightly higher, rising to 5,000 feet (1,524 meters) at Mount Tai, one of China’s most sacred mountains. The Shandong Hills meet the sea along a rocky and indented shoreline.
The Qin Mountains
The Qin (conventional Tsinling) Mountains in Shaanxi province are the greatest chain of mountains east of the Plateau of Tibet. The mountain chain consists of a high and rugged barrier extending from Gansu to Henan; geographers use a line between the chain and the Huai River to divide China proper into two parts—North and South. The elevation of the mountains varies from 3,000 to 10,000 feet (900 to 3,000 meters). The western part is higher, with the highest peak, Mount Taibai, rising to 12,359 feet (3,767 meters). The Qin Mountains consist of a series of parallel ridges, all running roughly west-east, separated by a maze of ramifying valleys whose canyon walls often rise sheer to a height of 1,000 feet (300 meters) above the valley streams.