Desertification or ?the diminution or destruction of the biological potential of land that can lead ultimately to desert-like conditions? is a sad fact to reckon with today. Indeed, almost 4 billion hectares of dry lands in the world have been affected by desertification, putting some 80 million people at risk in more than 100 countries.

There are several factors that combine to bring about land degradation and the reduction of resource potential of vast areas. Human exploitation oversteps the natural carrying capacity of the land resource system especially in less economically developed countries where there is an ever growing need to over-cultivate the land to feed an ever increasing number of mouths. Paradoxically, under-exploitation of land ? due to migration of people in various parts of sub-Saharan Africa -where villagers have migrated to cities in search of better employment opportunities ? has left vast areas of farming land exposed to soil erosion, wind deflation and leaching, all of which impoverish the soil.

Deforestation is itself a major culprit. In many tropical forests, trees are being felled at an alarming rate, either by shifting cultivators, who clear large patches of forest to practice subsistence agriculture for a few years before abandoning the land to infertility, or by commercial exploiters logging trees indiscriminately and unscrupulously for financial gains. Adverse climatic conditions, including severe recurrent droughts, as can be seen in the Sudano-Sahelian region of Africa, add to the list of causes of desertification.

The most obvious consequences of desertification relate to the reduction of biological and economic productivity and the pollution of water and air. In affected areas, there is a marked reduction of crop yield for humans as well as livestock, a scarcity of fuel wood, a decrease of river flow and ground water resources, the encroachment of sand that overwhelms productive land, settlements and infrastructures, flooding, sedimentation of water bodies, and the deterioration of human life due to the deterioration of life-support systems.

This entire chaotic situation leads to the need for more relief aid and the socio-economically and politically destabilizing inflation of huge masses of migrating environmental refugees. Desertification is one element of planetary environmental degradation that contributes to climate change, adding dust and carbon dioxide to the atmosphere when forests are burnt and disrupting and reducing the global carbon dioxide sink in particular.

Since it is a global threat and affected countries are poor, pre-emptive, corrective and rehabilitative measures to combat desertification must be largely supported by the powerful, industrialized countries in terms of finance, technology and know-how. The strategy must aim at developing and managing resources in dry lands on the one hand, and, on the other, stopping land degradation, establishing large scale green belts, introducing soil and water conservation systems, reclaiming new areas for productive use, finding renewable energy sources, re-afforesting affected areas and last, but not least, analysing results and evaluating experiments and research on the issue ? a tall order by all standards.

<B>Bashir Taleb</B>