Trans-Himalayas

Kangtissushan, a mountain system in China, in the southern part of the Tibetan Plateau. The mountains run almost parallel to the Himalayas, from which they are separated by a longitudinal subsidence, which occupies an enormous tectonic depression. The length of the mountains is about 1,600 km, and the width of the central portion is up to 300 km. The predominant elevations of the main peaks are 5,000-5,500 m. The highest peak is Mount Aling Kangri, 7,315 m. The passes (including Ding-La, Kongbo Pa, and Goring) lie at an altitude of 5,000 m and higher. The mountains are composed predominantly of Mesozoic granites, quartzites, schists, and limestones. Thick layers of acid lavas alternate with red beds.

The system of the Trans-Himalayas consists of several ranges with a latitudinal strike. The most significant in terms of length and altitude are the Aling Kangri in the north and the Nyenchen Tanglha and Kailas in the south. Between them are the secondary ranges (such as the Lapchung and Kanchung Kangri). The interior regions of the Trans-Himalayas are an alternation of chaotically situated broken chains and intermontane subsurface drainage basins at an altitude of about 4,500 m. There are lakes (Nam Tso and others) in the basins. The northern chains show little ruggedness and are marked by flat or dome-shaped peaks, shallow intermontane valleys, and intensive development of physical weathering processes. The slopes and the feet of the mountains are covered by loose weathering products. The southern branches of the Trans-Himalayas form the divide between the Indian Ocean and the closed drainage area of Tibet. They are almost a continuous chain of snow-covered mountains with high peaks, with large glaciers descending to the south and to the north. The surface of the southern chains is very rugged with deep, steep-sided gorges in which flow short but abundant rivers of the Tsangpo (Brahmaputra) and Upper Indus basins.

The climate as a whole is severe and in the northern part differs little from the climate of the Tibetan Plateau. The southern ranges are in the sphere of influence of the Indian monsoon. On the northern ranges, there are alpine cobblepebble desert landscapes, in places with low-humus and sometimes solonchak desert soils of a coarse mechanical composition. The vegetation does not form a solid cover. In the central basins of the Trans-Himalayas the landscapes are alpine low-grass steppe, and on the windward slopes there are alpine meadows with meadow grass, sheep’s fescue, and cushion-like perennial plants. There are no forests; tree-like juniper is encountered only near the lakes. The soils of the alpine steppes are shallow and do not have an illuvial-calcareous horizon. The lands are used basically as natural pastures. Farmed areas are encountered only in some places. Among the animals in the area, the most characteristic ungulates are the yak, sheep, the chiru, and the bharal, and of the predators, wolves and the Tibetan fox. On the southern slopes of the Nyenchen Tanglha and Kailas, one can clearly trace the altitudinal zonality of the landscapes. In the upper areas of the slopes there is a predominance of glaciers, snowfields, barren rocks, and alpine deserts. Meadow-steppe vegetation grows in the middle portion of the slopes. The southernmost chains are covered predominantly by mountain meadows.