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Land degradation

Almost 25 per cent of land is degrading globally.

A new study has concluded that 24 per cent of the land area globally is facing degradation.

The Global Assessment of Soil Degradation (GLASOD) has for almost 30-years studied the extent and severity of the decline in the quality of soil, water and vegetation around the world. This new study published in the journal Soil Use and Management has indicated that for the period 1981-2003, 24 per cent of the land has been degraded.

One of the authors, Dr David Dent of ISRIC - World Soil Information explains: “Degradation is primarily driven by land management and catastrophic natural phenomena.

“Our study shows the extent and severity of land degradation measured in terms of loss of net primary productivity, making allowance for climatic variability. Overall, a quarter of the world’s population depends directly on these degrading areas. The worst-hit areas are Africa south of the Equator, SE Asia and S China. The worst-affected countries, with more than 50 per cent of territory degrading are, in Africa, the Congo, Zaire, Equatorial Guinea, Gabon, Sierra Leone, Zambia and the most affected (95 per cent degrading) Swaziland; in Asia,  Myanmar, Malaysia, Thailand, Laos, Korea and Indonesia. In terms of the rural population affected, the greatest numbers are in China, with nearly half a billion, India, Indonesia, Bangladesh and Brazil. The usual suspects, such as the African Sahel and around the Mediterranean are much less affected.”

The researchers conclude that a more detailed analysis of land use history is needed to uncover the underlying social and economic drivers of land degradation.

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