Ressources en terres

Land degradation assessment

Leafless, dead trees cast little shade on the sere earth below. In time, they will crumble into dry dust, blowing over the baked soil of northern Senegal. Meanwhile, the average annual temperature continues to rise and the rains to decrease.

Land degradation: is the reduction in the capacity of the land to provide ecosystem goods and services and assure its functions over a period of time for the beneficiaries of these. Land degradation affects large areas and many people in dryland regions. Increased population pressures and excessive human expansion into drylands during long wet periods leave an increasing number of people stranded there during dry periods. The transfer of critical production elements to other uses (e.g. dry-season grazing lands) through the introduction of irrigated and non-irrigated cash crops, and the use of water for industrial and urban purposes at the expense of rural agricultural producers break links in traditional production chains in drylands. Where not compensated, such changes lead to the breakdown of the entire production systems. The removal of the protective cover to reduce competition for water and nutrients, ploughing, heavy grazing and deforestation all leave the soil highly vulnerable to wind erosion particularly during severe droughts. Heavy grazing around water points or during long droughts prevents or delays the regrowth of vegetation or favours only unpalatable shrubs.

Land degradation costs an estimated US$40 billion annually worldwide, without taking into account hidden costs of increased fertilizer use, loss of biodiversity and loss of unique landscapes.
The consequences of land degradation are reduced land productivity, socio-economic problems, including uncertainty in food security, migration, limited development and damage to ecosystems. Degraded land is costly to reclaim and, if severely degraded, may no longer provide a range of ecosystem functions and services with a loss of the goods and many other potential environmental, social, economic and non-material benefits that are critical for society and development.

Land Degradation Assessment in Drylands
The project started in 2006 with the general purpose of creating the basis for informed policy advice on land degradation at global, national and local level. This goal is to be realized through the  assessment of land degradation at different spatial and temporal scales and the creation of a baseline at global level for future monitoring. The project will complete its activity by 2010. More....

  Land degradation components

   Loss of biodiversity

  Salinization

  Water erosion

   Sand dune
   encroachment

  Rangeland
  degradation

   Outmigration

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