Included here is the Tibetan Plateau bordered by the eastern Pamirs and eastern Hindo Kush Mountains to the west, the Karakorum Range and Himalayas to the south, the Bayan Khara Shan Mountains to the east and the Transalai (Zaalai) Range to the north It is the highest, largest and youngest plateau on Earth with a mean elevation exceeding 4500 m.

Tibetan High Cold Desert

In the north, such as the northernmost parts of Chiangtang (northern Tibet), high cold desert conditions prevail. The landscape shaped by glaciations and frost weathering, is largely composed of rocky slopes and rubble-strewn valleys. Here the two endemic species Carex moorcroftii (Cyperaceae) and Ceratoides compacta (Chenopodiaceae) make up the bulk of the vegetation. The coldest and driest climate in Tibet occurs in the northwestern parts of the Chiangtang Plateau. Here there is an almost non-existent growing season. The few scattered plants include the endemic Ceratoides compacta (Chenopodiaceae), which rarely achieves more than about 8 % ground cover, and its few companion species include Pegeophyton scapiflorum and the endemic Hedinia tibetica (Brassicaceae). In the slightly warmer southern areas, plants such as Pennisetum flaccidum and several endemic species such as Artemisia wellbyi (Asteraceae) and Orinus thoroldii (Poaceae) may be found.  On the western Ali Mountain plateau, the cold desert community mainly consists of Ajania fruticulosa, the suffrutescent Cerotoides latens (a relict of the ancient Tethys flora) and the endemic perennial Christolea crassifolia (Brassicaceae). Above a altitude of about 4500 m feathergrasses such as Stipa brevifolia, S. glareosa and S. subsessiliflora enter the community, and on Mount Chiangchenma this desert vegetation reaches an altitude of 5200, where it forms the world’s highest desert.

References

Chang, D. H. S. 1981. The vegetation zonation of the Tibetan Plateau. Mountain Research and Development, 1: 29-48.

Walter, H. & Box, E. O. 1983. Deserts of Central Asia. In: Ecosystems of the World 5 - Temperate Deserts and Semi-Deserts. Ed. N. E. West. Elsevier Scientific Publishing Company.

Wang, W., Wang, Q., Li. S. & Wang, G. 2006. Distribution and species diversity of plant communities along a transect on the northeastern Tibetan Plateau. Biodiversity and Conservation, 15: 1811-1828.

Ward, F. K. 1936. A sketch of the vegetation and geography of Tibet. Proceedings of the Linnean Society of London, 148: 133-160.