What is desertification?

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What is desertification?

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Desertification is not the natural expansion of existing deserts but the degradation of land in arid, semi-arid, and dry sub-humid areas. It is a gradual process of soil productivity loss and the thinning out of the vegetative cover because of human activities and climatic variations such as prolonged droughts and floods. What is alarming is that though the land’s topsoil, if mistreated, can be blown and washed away in a few seasons, it takes centuries to build up. Among human causal factors are overcultivation, overgrazing, deforestation, and poor irrigation practices. Such overexploitation is generally caused by economic and social pressure, ignorance, war, and drought.

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Desertification is a process wherein semi-arid arable land is turned into desert, unable to sustain plant or animal life. Although desertification can be caused by natural processes, like climate change, it is generally agreed that human influences are greatly accelerating the rate of desertification worldwide. As pressures on the Earth grow due to increased population and global warming, it is estimated that the rate of desertification may start to rapidly increase, and it is already causing serious social and environmental problems in some African nations. In the United States, one of the most famous historical examples of desertification is the Dust Bowl of the 1930s, although the rapid destruction of grassland in the American west is comparable. In Africa, the rapidly expanding Sahara and serious desertification occurring in the Sahel region of West Africa are being cited by numerous humanitarian organizations as issues of concern. For humans, the reduction of usable land through d

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The source document for this Digest states: Summary for Decision-makers Desertification is defined by the U.N. Convention to Combat Desertification as “land degradation in arid, semiarid and dry subhumid areas resulting from various factors, including climatic variations and human activities.” Land degradation is in turn defined as the reduction or loss of the biological or economic productivity of drylands. This report evaluates the condition of desertification in drylands, including hyper-arid areas, by asking pointed questions and providing answers based exclusively on the reports generated for the MA. Desertification occurs on all continents except Antarctica and affects the livelihoods of millions of people, including a large proportion of the poor in drylands. Desertification takes place worldwide in drylands, and its effects are experienced locally, nationally, regionally, and globally. Drylands occupy 41% of Earth’s land area and are home to more than 2 billion people—a third o

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Desertification refers to the persistent degradation of dryland ecosystems by climatic variations and human activities. It occurs on all continents (except Antarctica) and affects the livelihoods of millions of people, including a large proportion of the poor in drylands. The U.N. Convention to Combat Desertification (UNCCD) defines it as “land degradation in arid, semiarid and dry subhumid areas resulting from various factors, including climatic variations and human activities.” Land degradation is in turn defined as the reduction or loss of the biological or economic productivity of drylands. In 2000, drylands, which occupy 41% of Earth’s land area, were home to a third of the human population, or 2 billion people. Ecosystem services are the benefits obtained by people from ecosystems, for instance crops, forage and wood. In drylands, water scarcity limits the production of such services provided by ecosystems. Persistent, substantial reduction in the provision of ecosystem services

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“…’desertification’ means land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities” — UNCCD, Article 1 Differing Interpretations Desertification is a term that has long been associated with drylands, which cover 40% of the land surface of the globe (Table 1) and are home to over one billion people, or 20% of the human population. Large areas of these drylands (in Asia, the Mediterranean, Africa, Oceania, and the Americas) are considered to be experiencing differing degrees of ‘desertification’ (Dean, et al. 1995, Hoffman, et al. 1995, Kassas 1995a, Le Houérou 1996, Mortimore 1998, Mouat and McGinty 1998). In many areas, natural vegetation has been eliminated or severely reduced through cultivation, overgrazing, and fuel gathering, and soils are eroding at accelerated rates. Many perceive that the capacity of the land to support human populations, livestock, and wild herbivores has thereby been subs

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