Deserts and xeric shrublands

"Xeric" redirects here. For the comic book grant foundation, see Xeric Foundation.
For xeric animals, see Xerocole.

Deserts and xeric shrublands are a biome characterized by receiving only a small amount of moisture,[1] usually defined as less than 250 mm of annual precipitation. They form the largest terrestrial biome, covering 19% of the earth's land surface area.[2]

Character of the biome

Main article: Desert
Further information: Xerophyte and Xerocole

Biodiversity: Deserts and xeric shrublands may have a very diverse and rich flora. Reptile fauna may also be very diverse with pronounced local endemism in some regions.

Minimum resources: Many species track seasonally variable and patchy resources and require large natural landscapes to persist. Available water sources and riparian habitats are critical for the persistence of many species.

Poor soils: Because biomass productivity is low, the litter layer is almost nonexistent and the organic content of surface soil layers is very low. Also, evaporation tends to concentrate salts at the soil surface.

Sensitivity to disturbance: As the desert is highly sensitive to grazing, soil disturbance, burning, plowing, and other cover alteration; restoration potential can be very low and regeneration very slow. The introduction of exotic species may be a serious problem.

Desertification

The conversion of productive drylands to desert conditions, known as desertification, can occur from a variety of causes. One is human intervention, including intensive agricultural tillage or overgrazing[3] in areas that cannot support such exploitation. Climatic shifts such as global warming or the Milankovitch cycle (which drives glacials and interglacials) also affect the pattern of deserts on Earth.

Desert and xeric shrublands ecoregions

Aldabra Island xeric scrub Seychelles
Arabian Peninsula coastal fog desert Oman, Saudi Arabia, Yemen
East Saharan montane xeric woodlands Chad, Sudan
Eritrean coastal desert Djibouti, Eritrea
Ethiopian xeric grasslands and shrublands Djibouti, Eritrea, Ethiopia, Somalia, Sudan
Gulf of Oman desert and semi-desert Oman, United Arab Emirates
Hobyo grasslands and shrublands Somalia
Ile Europa and Bassas da India xeric scrub Bassas da India, Europa
Kalahari xeric savanna Botswana, Namibia, South Africa
Kaokoveld desert Angola, Namibia
Madagascar spiny thickets Madagascar
Madagascar succulent woodlands Madagascar
Masai xeric grasslands and shrublands Ethiopia, Kenya
Nama Karoo Namibia, South Africa
Namib desert Namibia
Namibian savanna woodlands Namibia
Red Sea coastal desert Egypt, Sudan
Socotra Island xeric shrublands Yemen
Somali montane xeric woodlands Somalia
Southwestern Arabian foothills savanna Oman, Saudi Arabia, Yemen
Southwestern Arabian montane woodlands Saudi Arabia, Yemen
Succulent Karoo South Africa
Carnarvon xeric shrublands Australia
Central Ranges xeric scrub Australia
Gibson Desert Australia
Great Sandy-Tanami Desert Australia
Great Victoria Desert Australia
Nullarbor Plain xeric shrublands Australia
Pilbara shrublands Australia
Simpson Desert Australia
Tirari-Sturt's Stony Desert Australia
Western Australian mulga shrublands Australia
Deccan thorn scrub forests India, Sri Lanka
Indus Valley desert India, Pakistan
Northwestern thorn scrub forests India, Pakistan
Thar desert India, Pakistan
Baja California desert Mexico
Central Mexican matorral Mexico
Chihuahuan desert Mexico, United States
Colorado Plateau shrublands United States
Great Basin shrub steppe United States
Gulf of California xeric scrub Mexico
Meseta Central matorral Mexico
Mojave desert United States
Okanagan (South) shrub steppe Canada
Snake-Columbia shrub steppe United States
Sonoran desert Mexico, United States
Tamaulipan matorral Mexico,
Tamaulipan mezquital Mexico, United States
Wyoming Basin shrub steppe United States
Araya and Paria xeric scrub Venezuela
Aruba-Curaçao-Bonaire cactus scrub Aruba, Bonaire, Curaçao
Atacama desert Chile, Peru
Caatinga Brazil
Cayman Islands xeric scrub Cayman Islands
Cuban cactus scrub Cuba
Galápagos Islands xeric scrub Ecuador
Guajira-Barranquilla xeric scrub Colombia, Venezuela
La Costa xeric shrublands Venezuela
Leeward Islands xeric scrub Anguilla, Antigua and Barbuda, British Virgin Islands, Guadeloupe, Saint Martin, Saint Barthélemy, Saba, US Virgin Islands
Malpelo Island xeric scrub Colombia
Motagua Valley thornscrub Guatemala
Paraguana xeric scrub Venezuela
San Lucan xeric scrub Mexico
Sechura desert Peru
Tehuacán Valley matorral Mexico
Windward Islands xeric scrub Barbados, Dominica, Grenada, Martinique, Saint Lucia, Saint Vincent and the Grenadines
Saint Peter and Saint Paul Archipelago Brazil

See also

References

  1. ↑ Merriam-Webster.com Merriam-Webster Dictionary definition of xeric
  2. ↑ Lockwood, M. Managing Protected Areas: A Global Guide. p. 199.
  3. ↑ C.Michael Hogan. 2009. Overgrazing. Encyclopedia of Earth. Sidney Draggan, topic ed.; Cutler J. Cleveland, ed., National council for Science and the Environment, Washington DC

External links

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