Sung-Liao Plain

a level plain in Northeast China. Area, about 300,000 sq km. Elevations of 200 to 300 m predominate, dropping to under 100 m in the southwest. The Sung-Liao Plain is composed primarily of alluvial and lacustrine deposits; the section near the Yellow Sea is composed of marine deposits. Along the divide of the Sungari River and the Liao Ho there are hills composed of granites, gneisses, and basalts covered with a loessial mantle. Eolian forms of terrain, including dunes, are found in the west and southwest.

The Sung-Liao Plain has a temperate monsoonal climate with cold winters and rainy summers. The average January temperature is –8°C in the south and between –20° and –22°C in the north. The average July temperature is between 20° and 25°C. The annual precipitation ranges from 400 to 700 mm.

The steppes have chernozem and chestnut soils. In the west there are occasional salt marshes and loose sands; in the north some areas of ground remain frozen for years. In the northern most and easternmost regions of the plain there is forest steppe with forests of aspen, elm, oak, and birch. In the south and east the plain is densely populated and used for agriculture (producing kaoliang, green bristlegrass, corn, and, in the south, rice). Pastureland predominates in the west. Major cities in the plain are Harbin, Ch’angch’un, Chichihaerh, Shenyang, Fushun, and Chilin.