Deserts

Definition: Those ecosystems in which less than one third of the area has vegetation or other cover. In general, Barren Land has thin soil, sand, or rocks. Barren lands include deserts, dry salt flats, beaches, sand dunes, exposed rock, strip mines, quaries, and gravel pits.

Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data

Bare Exposed Rock: Those ecosystems characterized by areas of bedrock exposure, desert pavement, scarps, talus, slides, volcanic material, rock glaciers, and other accumulations of rock without vegetative cover. This does not include rock exposures in tundra regions. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Beaches: Those ecosystems along shorelines characterized by smooth sloping accumulations of sand and gravel. The surface is stable inland, but the shoreward part is subject to erosion by wind and water and to deposition in protected areas. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Dry Salt Flats: Those ecosystems occurring on the flat-floored bottoms of interior desert basins that do not qualify as wetlands. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Mixed Barren Land: Those regions in which a mixture of barren land features occurs and the dominant land use occupies less than two-thirds of the area. This includes, for example, a desert region where combinations of salt flats, sandy areas, bare rock, surface extraction, and transitional activities could occur in close proximity. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Sandy Areas Other Than Beaches: Those ecosystems composed primarily of dunes -- accumulations of sand transported by wind. These accumulations most commonly are found in deserts although they also occur on coastal plains, river flood plains, and deltas and in periglacial environments. This does not include sand accumulations in tundra areas. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Strip Mines, Quaries, and Gravel Pits: Those regions where vegetative cover and overburden are removed to expose such deposits as coal, iron ore, limestone, and copper. This includes inactive, unreclaimed, and active strip mines, quarries, borrow pits, and gravel pits until other cover or use has been established. This does not include unused pits or quarries that have been flooded. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

Transitional Areas: Those regions that are in transition from one land use activity to another. This transitional phase occurs when, for example, forest lands are cleared for agriculture, wetlands are drained for development, or when any type of land use ceases as areas become temporarily bare as con- struction is planned for such future uses as residences, shopping centers, industrial sites, or subur- ban and rural residential subdivisions. This also includes land being altered by filling, such as occurs in spoil dumps or sanitary landfills. (Definition Source: A Land Use and Land Cover Classification System for Use with Remote Sensing Data)

J.Balaji M.Sc (Microbiology)

9440031596 India
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Growing Deserts

It's hard to imagine that global warming would have much effect on the world's already hot deserts. But even small changes in temperature or precipitation could drastically impact plants and animals living in the desert. In some cases global warming is predicted to increase the area of deserts, which already cover a quarter of Earth.

Human activities such as firewood gathering and the grazing of animals are also converting semiarid regions into deserts, a process known as desertification. Population growth and greater demand for land are serious obstacles in the effort to combat this problem.

Threats

• Global warming is increasing the incidence of drought, which dries up water holes.
• Higher temperatures may produce an increasing number of wildfires that alter desert landscapes by eliminating slow-growing trees and shrubs and replacing them with fast-growing grasses.
• Irrigation used for agriculture, may in the long term, lead to salt levels in the soil that become too high to support plants.
• Grazing animals can destroy many desert plants and animals.
• Potassium cyanide used in gold mining may poison wildlife.
• Off-road vehicles, when used irresponsibly, can cause irreparable damage to desert habitats.
• Oil and gas production may disrupt sensitive habitat.
• Nuclear waste may be dumped in deserts, which have also been used as nuclear testing grounds.

Solutions

• More efficiently use existing water resources and better control salinization to improve arid lands.
• Find new ways to rotate crops to protect the fragile soil.
• Plant sand-fixing bushes and trees.
• Plant leguminous plants, which extract nitrogen from the air and fix it in the ground, to restore soil fertility.
• Use off-road vehicles only on designated trails and roadways
• Dig artificial grooves in the ground to retain rainfall and trap windblown seeds.

Arid land.

go green

A2. The hottest place in the World is believed to be the Afar Depression (a.k.a. Danakil depression) where at 155m below sea level, the temp has been recorded at 69oC. Death Valley in the US, is at 86m below sea level and has recorded a temperature of 57oC.

A1. The hottest temperature ever recorded was in the Sahara desert. In the US the hottest temperature recorded was in death valley, just a few degrees off of the temperature in the Sahara desert.