Deserts

Junggar Basin semi-desert

The Junggar Basin of northwestern China and Mongolia supports a vast expanse of semi-desert. Gaps in the mountains to the north permit enough precipitation to support thin steppe vegetation in many areas. Plant cover is insufficient for livestock, but sufficient for well-adapted species like Przewalski’s horse, Bactrian camel, specialized jerboas and geckos. Przewalski’s horse is extinct in the wild, but a small population of Przewalski’s camels still survives here. Most of the original habitat of this ecoregion has been converted to irrigated agriculture, and oil extraction threatens to destroy the remaining ecosystem.

Location and General Description

Situated between the Tian Shan and Altai Mountain Ranges of northwestern China, the Junggar Basin is similar in many ways to the larger Tarim Basin that lies across the Tian Shan Range to the south. Unlike the Tarim, the Junggar opens to the northwest through a series of large gaps in the encircling ranges. Because it is exposed in this way to the climatic influences of Siberia, the Junngar Basin has colder temperatures and more precipitation than the enclosed basins to the south. Mean annual precipitation in the center of the basin varies from 80 to 100 millimeters (mm); the periphery receives from 100 to 250 mm.

This basin holds the Gurbantunggut Desert, China’s second largest. Because there is ample runoff from the surrounding mountains, the basin also supports several lakes, the largest of which is Lake Saissan in Kazakhstan. Because the north slope of the Tian Shan receives more precipitation than other mountain ranges in this part of China, the plains at the southern margin of the Junggar Basin are well suited to irrigated agriculture.

Vegetation within the desert consists of a thin scrub of Anabasis brevifolia while the peripheral areas support a dwarf woodland dominated by saxaul bush (Haloxylon ammodendron) and the gymnosperm Ephedra przewalskii. Because the Gurbantunggut Desert is moist enough to support some vegetation, sands have been stabilized in most places. This desert consists of only about 5 percent shifting dunes, compared with the Taklimakan of the Tarim Basin where 85 percent of the area consists of shifting dunes. Biologically rich meadows, marshland, and riparian communities originally occurred at the foot of the mountains, but nearly all of these places have been converted to irrigated agriculture during recent centuries. The process has speeded up in recent decades, as the Chinese government is eager to translocate people to places like this from the crowded eastern portion of the country.

Oases in the eastern part of the Junggar Basin support poplar (Populus diversifolia), a tree that forms deciduous forest stands in places where snowmelt from the mountains raises the water table close to the surface. Nitraria roborovsky, N. sibirica, Achnatherum splendens, tamarisk (Tamarix sibirimosissima), and willow (Salix ledebouriana) also flourish in the oasis areas. Caragena and other shrubby legumes provide good quality browse for wild and domestic ungulates. On sand dunes Nitraria sphaerocarpa is predominant.

Biodiversity Features

The Junggar Basin is one of the last places where Przewalski’s horse (Equus przewalskii) was known to survive in the wild. A few centuries ago, two subspecies occurred from eastern Mongolia to as far west as central Europe, inhabiting productive forest and plain habitat. Over time, the horse was marginalized to steppe and semi-desert habitats. Today, this species is probably extinct in the wild. Although captive populations comprise 500 individuals, because these are descended from an original captive population of only 12 animals, loss of genetic diversity and inbreeding is a serious concern. The Junggar Basin is one place where Przewalski’s horse could be reintroduced in the future, with proper measures to safeguard its habitat. Today, several international efforts are underway to reintroduce this species to its historic homeland in Central Asia.

caption Aqik Lake plain, Arjin Mountains Nature Reserve, Xinjiang, China. (Photograph by WWF)

The northeastern part of the Junggar Basin lies in Mongolia and includes the Dzungarian section of Great Gobi National Park, an International Biosphere Reserve. The Dzungarian, which is largely desert steppe, provides important habitat for the world's largest remaining herds of wild ass (Equus hemionus) as well as herds of goitered gazelle (Gazella subgutturosa). The Dzungarian was also the last refuge of Przewalski's horse, the world's last truly wild horse. Some of the last remaining wild Bactrian camels (Camelus ferus) survive in Great Gobi National Park, which extends into both the Junggar Basin and the Alashan Plateau, the adjacent ecoregion to the east. This portion of the Junggar Basin provides excellent habitat for the wild camels because it is moist enough to support some scrub vegetation.

This ecoregion contains a single endemic mammal, Cheng's jird (Meriones chengi). Cheng's jird is a gerbil that is classified by IUCN as critically endangered. There are also several species of the small, rodent-like mammals called jerboas (family Zapodidae) that inhabit the Junggar Basin. Jerboas comprise a small family of mammals that are adapted to burrowing and jumping in sandy habitats. Their hind legs are as much as five times the length of their forelegs, and they have long, flexible tails. Several species are endemic to the Central Asian deserts and are capable of jumping as far as 3 meters (m).

Other species of special significance include the plate-tailed gecko (Teratoscincus przewalskii) a beautifully colored, nocturnal lizard endemic to Central Asia, and other reptiles such as the Gobi gecko (Cyrtapodion elongatus) and sand boa (Eryx tataricus).

Current Status

Nearly all of the original meadow, marsh, and riparian habitat in the Junggar Basin has been converted to irrigated agriculture. The region has seen recent large increases in human population due to migration and translocation from the eastern part of China.

Types and Severity of Threats

Oil exploration and extraction is potentially damaging to this ecoregion, unless accompanied by careful mitigation.

In the more pristine Dzungarian region of Mongolia, threats include uncontrolled motor-vehicle use and overconsumption and pollution of scarce natural water resources by humans and domestic livestock. Overgrazing is also a threat in some areas.

Additional information on this ecoregion

Further Reading

  • Barthel,H. 1983. Die regionale und jahreszeitliche Differenzierung des Klamas in der Mongolischen Volksrepublik. Gartenbau 25: 85-86, Berlin.
  • Conservation International
  • Equine Veterinary Network.
  • Geographical Survey of Xinjiang Province
  • Grubov, V.I. 1999. Plants of Central Asia, vol. 1 Science Publishers, Inc., Enfield, New Hampshire, USA. (translated from: Rasteniya Central’nov Asii, vol. 1, 1963. Nauka Publishers, Leningrad). ISBN: 9781578080601
  • Haase, G. 1983. Beitrage Zur Bodengeographie der Mongolischen Volksrepublik. Studia geogr. 34: 231-367, Brno.
  • Laidler, L. and K. Laidler. 1996. China’s threatened wildlife. Blandford, London. ISBN: 0713723726
  • MacDonald, D. editor. 1999. The encyclopedia of mammals. Barnes and Noble Books. ISBN: 0760719411
  • MacKinnon, J. 1996. Wild China. The MIT Press, Cambridge MA. ISBN: 0262133296
  • MacKinnon, J., Meng Sha, C. Cheung, G. Carey, Zhu Xiang and D. Melville. 1996. A biodiversity review of China. Worldwide Fund for Nature (WWF) International, Hong Kong. ISBN: 0198549407
  • Man, J. 1997. Gobi: Tracking the Desert. Yale University Press, New Haven, CT ISBN: 0297818597
  • Mongolia Ministry for Nature and Environment, United Nations Development Programme (UNDP)/Global Environment Facility (GEF), and World Wide Fund for Nature (WWF). 1996. Mongolia’s wild heritage. Avery Press, Boulder, Colorado. ISBN: 0937321044
  • Murzayev, E. M. 1971. The Deserts of Dzungaria and the Tarim Basin. In S. R. Eyre, editor, World vegetation types. Columbia University Press, New York.
  • United Nations in Mongolia
  • Zhao, Ji., editor. Zheng Guangmei, Wang Huadong, Xu Jialin. 1990. The Natural History of China. McGraw Hill Publishing Company, New York ISBN: 0070107521

Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

 

Glossary

Citation

Fund, W. (2014). Junggar Basin semi-desert. Retrieved from http://www.eoearth.org/view/article/51cbee457896bb431f696947

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