Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature.[ ] and xeric (Ancient Greek ξηρός 'dry') form the largest terrestrial biome, covering 19% of Earth's land surface area.[
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Temperature extremes are a characteristic of most deserts. High daytime temperatures give way to cold nights because there is no insulation provided by humidity and cloud cover. The diversity of climatic conditions, though quite harsh, supports a rich array of habitats. Many of these habitats are ephemeral in nature, reflecting the paucity and seasonality of available water.[ Woody-stemmed shrubs and plants characterize vegetation in these regions. Above all, these plants have evolved to minimize water loss. Animal biodiversity is equally well adapted and quite diverse.][
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Degradation
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
Woody plant encroachment
Xeric shrublands can experience woody plant encroachment, which is the thickening of bushes and shrubs at the expense of grasses.
Ecoregions
The World Wide Fund for Nature highlights a number of desert that have a high degree of biodiversity and endemism:[
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The Nama Karoo of Namibia has the world's richest desert fauna.
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The Carnarvon xeric shrublands of Australia are a regional center for endemism.
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The Chihuahuan desert may be the most biodiversity desert ecoregion in the world.
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The Sonoran Desert and Baja deserts of Mexico are unusual desert communities dominated by giant columnar cactus.
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Madagascar spiny forests
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Atacama Desert
See also
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Xeriscaping — gardening or landscaping in xeric environments
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— animals adapted to xeric environments
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— plants adapted to xeric environments
External links
