The Northeast Plain, the largest of China?s plains and its major heavy industrial base, lies between the Greater and Lesser Hinggan and the Changbai ranges. Also known as the Songliao Plain, it is made up mainly of the alluvial deposits of the Liaohe, Songhua and Nenjiang rivers and stretches from the middle Nenjiang valley in the north to the Liaodong Bay in the south. It covers 350,000 square kilometers in northeast China, measuring 1,000 kilometers from north to south and 400 kilometers from west to east in its widest part. The Northeast Plain consists of three sections: the Songnen Plain in the Liohe valley, and the Sanjiang (Three-River) Plain at the confluence of the Songhua, Wusuli and Heilong rivers. Most of the northeast Plain is less than 200 meters above sea level, the watershed of the Songhua and Liaohe rivers near Changchun being a little higher in elevation (200-250 meters).

The Northeast Plain is in the temperate humid and semi-humid zone. Although its temperature is low in winter and its freezing period long, its high summer temperature and its famous fertile black soil are ideal for crop growth. Its main crops include soya beans, sorghum, wheat, sugar-beet, flax and rice. The Northeast Plain was developed later than the two other major plains. The northern part of the Songnen Plain and the entire Sanjiang Plain were desolate wasteland known as the ? Great Northern Wilderness? before 1949. Part of the region has now been turned into a farming area, although much of the land there remains to be brought under the plough. The Northeast Plain is an important commodity grain grower.

The Northeast Plain has a well-developed industry, including iron and steel making in Anshan, coal mining in Fushun and Fuxin, machine-building in Shenyang, Harbin and Qiqihar, automobile manufacture in Changchun, chemical production in Jinlin and Shenyang, and oil industry in Daqing.

The North China Plain, an important agricultural region with the largest cultivated acreage in China, is situated in eastern China in the lower Huanghe River valley, bordering on the Taihang and Funiu ranges in the west, the coasts of the Huanghai and Bohai seas and the Shandong Hills in the east, the Yanshan Mountains in the north, the Tongbai and Dabie ranges in the southwest and on northern Jiansu and Anhui in the southeast where it links with the Middle-Lower Changjiang (Yangtze River) Plain. With a total area of 300,000 square kilometers, the North China Plain is the second largest in China, embracing the municipalities of Beijing and Tianjin and provinces of Hebei, Shandong, Henan, Anhui and Jiangsu.

Mainly the product of the alluvial deposits from the Huanghe, Huaihe and Haihe rivers the North China Plain is also called the Huang-Huai-Hai Plain. It has a low and gentle terrain mostly less than 50 meters above sea level. The lower Huanghe River travels across the central part of the plain and divides it into two sections. The northern section, in the Haihe valley, is called the Heihe Plain or Hebei plain; and the southern one, in the Huaihe valley, is called the Huang-Huai Plain. In the past several decades, agricultural development has been furthered by comprehensive measures taken to harness the three rivers, which have often caused floods in the plain. With smooth terrain, fertile soil, hot and wet summers, and an annual precipitation of 600 mm.--all conducive to crop growth--the North China Plain has a long history of agricultural development. Its major crops include wheat, maize, cotton, peanuts and tobacco. The vast, flat shallows on the shores of the Bohai and Huanghai seas are ideal salt-fields. Crisscrossed by railways, the North China Plain is easily accessible and has well-developed mining and other industries. Its major cities include Beijing, Tianjin, Shijiazhuang, Tangshan, Zhengzhou, Jinan and Xuzhou.?

The Middle ?Lower Changjiang (Yangtze River) Plain?located in the sub-tropics with hot summers, plentiful rainfall and fertile soil?consists of a series of plains of vary in width on both sides of the Yangtze River, in the section from the Three Gorges in the west to the coast in the east. It is bounded by the Huang-Huai Plain in the north and the Jiangnan Hills in the south, and sprawls over the provinces of Hubei, Hunan, Jiangxi, Anhui, Jiangsu and Zhejiang and the municipality of Shanghai.

Created by mud and silt from the Yangtze River and its tributaries, the Middle-Lower Changjiang (Yangtze River) Plain covers an area of 200,000 square kilometers, mostly less than 50 meters above sea level. It includes four sections: the Lianghu (Two-Hu) Plain in northern Hunan and central ?south Hubei and the Poyang Lakeside Plain in Jiangxi, both in the middle Yangtze River valley; and Central Anhui Plain and the Yangtze River Delta between Jiangsu and Zhejiang, both in the lower Yangtze River valley.

Unlike the flat, open Northeast and North China plains, the Middle-Lower Changjiang (Yangtze River) Plain contains rolling hills and hillocks in its north and south as well as towering mountains, such as Lushan, Huangshan and Dabieshan. It is chequered with streams and rivers, and lakes, including the major freshwater lakes Dongting, Poyang, Taihu, Gaobao, Chaohu and Honghu, giving it the name ?water country?. These rivers and lakes are a rich source of fish, shrimps, water chestnuts, lotus seed and root and reeds. It is known for intensive cultivation in farming, and abounds in rice, cotton, wheat, rapeseed and silk. Long referred to as a ?land of fish and rice?, it is one of the country?s major grain-producing regions.

The Middle-Lower Changjiang (Yangtze River) Plain has a well-developed economy, convenient communications and a dense population. Its major cities include Shanghai, Nanjing, Hangzhou, Hefei, Nanchang and Wuhan.

Other Large Plains--The Hetao Plain, an alluvial plain in the middle Huanghe River valley, covers a total area of 25,000 square kilometers. A major faming area of Inner Mongolia and Ningxia, it includes the Yinchuang (Xitao) Plain in Ningxia, the Houtao Plain and Tumochuan (Qiantao) Plain in Inner Mongolia. The Weihe (Guanzhoug) Plain in central Shaanxi covers an area of 13,000 square kilometers and has bee known for its irrigation projects since ancient times. Located here are the historically renowned cities of Xian and Xianyang. The Chengdu (Western Sichuan) Plain in northwestern Sichuan Basin has an area of 6,000 square kilometers rich in natural resources and is known as a ?land of affluence?. The Tainan Plain in southwestern Taiwn has an area of 5,000 square kilometers. The 11,000-square-kilometer Zhujiang Delta in central-south Guangdong, one of the country?s most densely populated regions, has well-developed agriculture, large coastal plains include the Chaozhou-Shantou Plain in Guangdong and the Ningshao Plain in Zhejiang.

(china.org.cn)