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Interlinkages
Desertification and Land Degradation
    Current trends
  • Desertification and drought are problems of a global dimension that affect more than 900 million people in 100 coun- tries, some of them among the least developed in the world.
  • 3.6 billion hectares, 25 percent of the Earth's land area, are being affected by land-degradation. Desertification is occur- ring to some extent on 30 percent of irrigated areas, 47 percent of rainfed agricultural lands, and 73 percent of rangelands.
  • An estimated I.5-2.5 million hectares of irrigated land, 3.5-4.0 million hectares of rainfed agricultural land, and about 35 million hectares of rangelands lose all or part of their productivity every year due to land-degradation processes.

    Underling causes

  • Complex interactions among physical, biological, political, social, cultural, and economic factors cause desertification.
  • Population growth and the need for food production in ecologically fragile arid and semi-arid lands, is putting too much pressure on the ecosystems.
  • Many land-use projects are designed with little understanding of the socioeconomic conditions of the population and the dynamics and sustainability of the natural-resource base.
  • Inappropriate economic policies that undervalue natural resources and encourage misuse.

    Projected impact of human activities on desertification

  • By 2025 the number of people adversely affected by desertification is expected to double to I.8 billion people.

    Social and economic consequences of desertification

  • Intensive population pressures and improper resource use degrade the land, reduce its productivity, decrease food security and health prospects, increase poverty, and increase pressures for large-scale migration. The annual income lost worldwide due to desertification is estimated to be $42 billion.
  • Desertification and land degradation affect the regional and global energy balance, reduce carbon sequestration and storage, and increase carbon emission.
  • Land degradation in dryland systems can lead to the loss of genetic and species diversity. Drylands contain a significant endowment of plant and animal species biodiversity, a vital source of genetic materials that include important sources of medical, commercial, and industrial products.
  • Land degradation causes loss of productivity and impairment of aquatic ecosystems through sediment pollution, salt intrusion and general environmental degradation.

    Technologies, policies, and measures to mitigate desertification

  • Providing family planning, health, and education services (especially for women).
  • Developing programs to eradicate poverty and promote alternative livelihood systems.
  • Developing effective and sustainable uses of land and natural resources that do not endanger their future productivity.
  • Integrating anti-desertification schemes into national environment and development planning.
  • Involving beneficiaries in the planning and management of resources, to ensure equitable access.

    Status of international agreement

  • The Desertification Convention was originally signed by 116 countries in Paris in June I 994. The Convention came into force December 26, 1996, and 128 countries had ratified the convention by mid-1998. The first Conference of Parties (COP) was held in fall 1997 in Rome, Italy.



Source:
"Protecting Our Planet, Securing Our Future" UNEP / U.S. NASA / World Bank, 1997