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Desertification

Land Management

Land management measures that combat desertification focus on improving sustainability and long-term productivity. Though damaged areas cannot always be restored to their pre-desertified conditions, they can often be reclaimed by designing a new state that can better withstand cultural and climatic stresses. Specific measures include developing a resilient vegetation cover of mixed trees, shrubs, and grasses suitable to local conditions that protects the soil from wind and water erosion and compaction. Redistribution of water resources, and redesign of water delivery systems, can reduce the effects of salination, groundwater depletion, and wasteful water use. Finally, limiting the agricultural demands made on drought-prone arid and semi-arid lands can be accomplished by encouraging farmers to grow drought-tolerant plants, and to move water-hungry crops, like cotton and rice, to more suitable climates.

Land management methods that halt or reverse desertification have been known in the United States since the end of the nineteenth century, but they have only recently have they been put into widespread use. United States federal policies do support soil conservation in croplands and rangelands, but only about one third of such land is under federal protection. The United States government has strongly supported the autonomy of private landowners and corporations who, in turn, have often traded sustainable land-use practices for short-term profits. Even the ravages of the dust bowl did not result in widespread anti-desertification measures.

In the developing world, particularly in Africa, where poverty and political unrest are common, progress toward mitigation of desertification and its devastating social costs has been slow. Many of the world's poorest people, who live in countries with the weakest and most corrupt governments, rely on unsustainable agriculture and nomadic grazing to subsist. Many African countries, including Niger, Mali, and Senegal, have experienced positive results with implementation of a system of local self-regulation. This strategy, encouraged by the United Nations, involves a pastoral association or a community assuming responsibility for maintaining a water source and its surrounding rangeland, while receiving free veterinary and health services. By these and similar means, cultural habits, subsistence needs, economic concerns, and ecological conservation can be addressed in a single, integrated program. Furthermore, such programs help local communities reduce their dependence on ineffective or corrupt centralized governments, and on the international aid community. Such comprehensive anti-desertification programs have been very successful on a limited scale, but progress has been slow because of the extreme poverty and sociopolitical powerlessness of the communities involved. The key to the success of any anti-desertification program is the need to adapt to local conditions, including those associated with climate, ecology, culture, government, and historical land-use.

Resources

Books

Mainguet, M. Aridity: Droughts and Human Development. Springer Verlag, 1999.

Press, Frank, and Raymond Siever. Understanding Earth. Chapter 14: Winds and Deserts. New York: W.H. Feeman and Company, 2001.

Sheridan, David. Desertification of the United States. Washington, DC: Council on Environmental Quality, U.S. Government Printing Office, 1981.

Other

National Atmospheric and Space Administration. "From the Dust Bowl to the Sahel." Distributed Active Archive Centers Earth Observatory. May 18, 2001. [cited October 24, 2002] <http://earthobservatory.nasa.gov/Study/DustBowl/>.

Public Broadcasting System/WGBH. "Surviving the Dust Bowl." The American Experience. 1999 [cited October 24, 2002]. <www.pbs.org/wgbh/amex/dustbowl/>.

United Nations Convention to Combat Desertification. "Text and Status of the Convention to Combat Desertification." February 14, 2002 [cited October 24, 2002]. <http://www.unccd.int/convention/menu.php>.


Marjorie Pannell
Laurie Duncan

KEY TERMS

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Arid land

—Land receiving less than 10 in (25 cm) of rainfall annually, with a high rate of evaporation and supporting a thin vegetation cover, chiefly of grasses and shrubs.

Gradualism

—A slow rate of change, implying that processes are spread out over time as well as space.

Sahel region

—A semi-arid region along the southern border of the Sahara Desert in western Africa with a dry savanna type of vegetation. In recent years this region has been encroached on by the Sahara Desert, partly as a result of poor land management.

Additional topics

Science EncyclopediaScience & Philosophy: Dependency - The Intellectual Roots Of Dependency Thinking to Dirac equationDesertification - The Sahelian Drought And United Nations Convention To Combat Desertification, Desertification In North America, Processes Of Desertification