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The Greater Khingan Range (simplified Chinese: 大兴安岭; traditional Chinese: 大興安嶺; pinyin: Dà Xīng'ānlǐng; Mongolian: Их Хянганы нуруу; Manchu: Amba Hinggan), also called the Greater Hing'an Range or Greater Hinggan Range, is a volcanic mountain range in northeast China. The range extends roughly 1,200 kilometres (750 mi) from north to south, narrowing toward the south. It divides the Manchurian plain of northeastern China to the east from the Mongolian Plateau of Inner Mongolia to the west.
The area has an elevation of 1,200 to 1,300 metres (3,900 to 4,300 ft), and the highest peak reaches 2,035 metres (6,677 ft). The range is much broader in the north, at 306 kilometres (190 mi), than it is in the south, at 97 kilometres (60 mi). It was formed during the Jurassic Period (roughly 200 to 145 million years ago), and is essentially a tilted fault block; its ancient fault line forms its eastern edge, facing the Northeast Plain. The ranges are markedly asymmetrical, with a sharp eastern face and a more gentle western slope down to the Mongolian Plateau at an elevation of 790 to 1,000 metres (2,590 to 3,280 ft). The eastern slopes are more heavily dissected by the numerous tributaries of the Nen and Sungari rivers, but generally the mountains are rounded with flat peaks. The ranges are composed largely of igneous rocks (i.e., formed through the solidification of magma).
Dense forests cover the range. This eco-region is noted for its Daurian flora, which has influence from the adjacent Siberian and Manchurian floras. The mountains form an important climatic divide. They take most of the precipitation from the southeasterly winds and produce a comparatively wet climate (precipitation exceeds 500 millimetres (20 in) annually) that contrasts sharply with the arid region to the west. The northern section of the mountains is the coldest part of eastern China, with extremely severe winters (mean temperature −28 °C (−18 °F)) and with large areas under permafrost. Forests of larch, birch, aspen, and pine cover the region with shrubs covering at the highest elevations. The rich and diverse wildlife include deer, elk, marten, hare, and many other fur-bearing animals. However, the central and southern sections of the range have considerably warmer temperatures and drier climates than in the north, with January temperatures of about −12 °C (10 °F), annual precipitation of 250–300 millimetres (9.8–11.8 in), and comparatively light snowfalls. The coniferous forests of the north gradually give way in the south to broad-leaved forests and then to patches of grassland interspersed with woodland. In the south, the forests cover the higher ground above 1,500 metres (4,900 ft), while tall grasses cover the majority of the area. In May 1987 the devastating Black Dragon fire swept the Da Hinggan forests, destroying perhaps 10,000 square kilometres (3,900 sq mi) of timber. The Black Dragon Fire gained its name from the Heilong Jiang (“Black Dragon River”; i.e., the Amur) that flows through the area.
The Da Hinggan region was to a large extent unexplored until the 20th century. The exploitation of the northern part of the region began with the construction early in the 20th century of the first railway across the mountains—the Chinese Eastern Railroad from Qiqihar in Heilongjiang province, to Manzhouli, north of Lake Hulun, in northeastern Inner Mongolia near the border with Russia. During the Japanese occupation of Northeast China (Manchuria; 1931–45), a number of railways were constructed into the mountains north and south of this line in order to extract lumber, the most important being those running into the area north of Tulihe (Tol Gol). These lines were later extended eastward into the Yilehuli Mountains, which strike east and west and join the Da Hinggan Range to the Xiao Hinggan Range. Farther south a more recent line follows the Tao’er River valley northwest from Baicheng in Jilin province to Suolun (Solon) and the hot springs at Arxan in Inner Mongolia.