Deserts (main)

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Deserts


Desert biomes cover about one fifth of the Earth's surface and are defined to occur where rainfall is less than 50 centimeters per year. Although most deserts, such as the Sahara of North Africa and the deserts of the southwestern USA, Mexico, and Australia, occur at low latitudes, another kind of desert, cold deserts, occur in the basin and range area of Utah and Nevada and in parts of western Asia. Most deserts have a considerable amount of specialized vegetation, as well as specialized vertebrate and invertebrate animals. Soils often have abundant nutrients because they need only water to become very productive and have little or no organic matter. Disturbances are common in the form of occasional fires or cold weather, and sudden, infrequent, but intense rains that cause flooding.

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    A polar desert is a biome with precipitation below 250 millimeters per annum and a mean temperature during the warmest month of less than 10 degrees Celsius. Typically... More »
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    Cactus is a family of plants that are specially adapted to survive arid conditions, most often having leaves reduced to spines, and succulent characteristics. The scientific... More »
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Recently Updated
Desertelephantsnwnamibia.jpg Namibian savanna woodlands Last Updated on 2015-09-07 13:29:18 WWF Terrestrial Ecoregions Collection The Namibian savanna woodlands ecoregion covers the Great Escarpment that delimits the interior of southern Africa from both the Kaokoveld Desert and Namib Desert. This broken and deeply dissected escarpment is an area of high endemism for plants, invertebrates, amphibians, reptiles, mammals and birds. The northern area of the ecoregion, the Kaoko escarpment, is an endemism "hotspot" (area of extremely high species richness and endemism). The Namibian savanna woodlands comprise a land area of approximately 87,100 square miles. This northern area is poorly protected and is under threat from poaching, off-road driving, and to a lesser extent from farming, and resultant habitat fragmentation; much of this destabilisation in the Angolan portion of the ecoregion stems from the Cuban mercenaries aided... More »
Namibdesertcentralflight.jpg Kaokoveld Desert (Deserts) Last Updated on 2015-07-14 14:38:13 WWF Terrestrial Ecoregions Collection The Kaokoveld Desert represents the northern area of the vast Namib Desert. It is a harsh, arid landscape of rugged mountains, gravel plains and shifting sand dunes. Surface water is scarce, with only one perennial river flowing through the region, the Kunene River. However, the dry riverbeds transecting the area are the lifelines of the desert. They are well vegetated and are home to large mammals such as African Elephant, Black Rhino and Giraffe. The remainder of the landscape is poorly vegetated and extremely arid. Coastal fogs allow a range of interesting, desert-adapted animal species to survive in this low-rainfall environment. The relict gymnosperm Welwitschia mirabilis, which represents the sole surviving member of its family, is found throughout the ecoregion. The Kaokoveld Desert is well protected in... More »
5257365421 6f354b518a o.jpg Madagascar spiny thickets Last Updated on 2015-06-25 20:16:56 WWF Terrestrial Ecoregions Collection The Madagascar spiny thickets or spiny desert of southern Madagascar, also referred to as deciduous thicket, is a globally distinctive ecoregion. This ecoregion is part of the Deserts and Xeric Shrublands biome, within the Afrotropics Realm. While the island of Madagascar is notable for exceptional levels of endemic plants and animals, the spiny thicket is particularly distinctive with 95 percent of the plant species endemic to the ecoregion. Members of the endemic Didiereaceae family present dominate the thicket, which have similar xeric adaptations to New World cacti, such as small leaves and spines, but with the Madagascar spiny thickets displaying more woody rather than succulent characteristics. There are a total of 288 recorded vertebrate taxa in the Madagascar spiny thickets, including several endemic... More »
AsaguaronpsceneIMGP45931295838737.jpg Cactus (Deserts) Last Updated on 2015-04-08 23:49:44 Cactus is a family of plants that are specially adapted to survive arid conditions, most often having leaves reduced to spines, and succulent characteristics. The scientific family name Cactaceae is applied to this group comprising 121 different genera. This plant family is concentrated in the Americas and has a surprisingly broad latitude range in both the Northern and Southern Hemispheres. A considerable number of cacti species are threatened, chiefly due to habitatlossto agriculture, trampling by illegal human immigration into the southwestern USA, large-scale desert solar power projects, as well as overcollecting. The cactus family is generally considered native to the Americas.A notable exception is Mistletoe cactus, Rhipsalis baccifera, which is thought to have spread, fairly recently,from the American tropics to the subtropics and the deserts of the... More »
NamibiasussusDSCN2004.jpg Namibia (Deserts) Last Updated on 2014-07-07 16:10:29 Namibia is a nation of over two million people in southern Africa, bordering the South Atlantic Ocean, between Angola to the north and South Africa to the south. Namibia is mostly high plateau with the Namib Desert along the coast and the Kalahari Desert in east. It is one of the least densly populated nations in the world. Namibia's major environmental issues include: limited natural fresh water resources; desertification; wildlife poaching; habitat fragmentation; and, land degradation which has led to few fully protected intact conservation areas. Most of the country is susceptible to prolonged periods of drought. South Africa occupied the German colony of Southwest Africa during World War I and administered it as a mandate until after World War II, when it annexed the territory. In 1966 the Marxist Southwest Africa People's... More »
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