Search results
Results from the WOW.Com Content Network
Desertification is a gradual process of increased soil aridity.Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."
Desertification is the process by which a piece of land becomes a desert, as the word desert implies. [3] The loss or destruction of the biological potential of the land is referred to as desertification. [4] It reduces or eliminates the potential for plant and animal production on the land and is a component of the widespread ecosystem ...
The driest areas usually receive 110–200 mm (4.3–7.9 in) of rain per year, [1] and the wettest just a little over 500 mm (20 in). The surrounding Kalahari Basin covers over 2,500,000 km 2 (970,000 sq mi) extending farther into Botswana, Namibia, and South Africa, encroaching into parts of Angola , Zambia and Zimbabwe .
Desertification is one of the issues of environmental concern in Nigeria, particularly the northern part of the country. According to UNEP [4] in 1993, Northern Nigeria has one of the highest rates of deforestation in the world at about 3.5%, caused by land degradation, increase in agricultural intensity, over-grazing of livestock, and demand for fuel by cutting down trees.
The largest hot desert in the world, the Sahara, covers 9 million square kilometres (3.5 × 10 ^ 6 sq mi) and contains several ergs, such as the Chech Erg and the Issaouane Erg in Algeria. [5] Approximately 85% of all the Earth's mobile sand is found in ergs that are greater than 32,000 km 2 (12,355 sq mi), [ 6 ] the largest being the Rub' al ...
But included in that 10–20% of land is the approximately 9 million square kilometers of seasonally dry-lands that humans have converted to deserts through the process of desertification. [7] The tallgrass prairies of North America, on the other hand, have less than 3% of natural habitat remaining that has not been converted to farmland. [12]
The characteristics of hot deserts include high temperatures in summer; greater evaporation than precipitation, usually exacerbated by high temperatures, strong winds and lack of cloud cover; considerable variation in the occurrence of precipitation, its intensity and distribution; and low humidity.
Drylands cover 41.3% of the Earth's land surface, including 15% of Latin America, 66% of Africa, 40% of Asia, and 24% of Europe. There is a significantly greater proportion of drylands in developing countries (72%), and the proportion increases with aridity : almost 100% of all hyper-arid lands are in the developing world.