During the 1992 Earth Summit in Rio de Janeiro, Brazil, African governments called for a desertification convention, because they felt that the improvement of food production and land management had not been adequately addressed.

The Convention to Combat Desertification was adopted in June 1994 and by May 1995, a total of 105 countries had signed the international treaty. Eight SADC countries have signed the convention. Lesotho is the only SADC country along with 34 other states, that have so far ratifies it. Three SADC countries – Botswana, Mozambique and Swaziland- had not yet signed. Fifteen more countries need to ratify it before the CCD becomes an international law.

The ratification and coming into force of the convention, which focuses particularly on African drylands, is expected by 1997. It outlines the ways in which governments, donor agencies, local people, and Non-Governental Organisations (NGOs) could best work together to combat desertification.

Unlike other international environmental treaties, it includes concrete national commitments for practical action, particularly at the local level where desertification must primarily be fought. It places great emphasis on the machinery needed to implement it and monitor it progress.

The desertification convention is very unique because it calls for close collaboration between non-governmental and community-based organisations, and governments; participatory rural appraisal, involving the local communities; and it has a special mention od women’s participation.

Desertification is land degradation processes which occur in dry sub-humid areas as a result of various factors, including climatic variations and human activities.

It is a process of conversion of non-desert land to desert, usually as a result of overgrazing, depletion of organic matter in the soil, overuse of groundwater, changing patterns in precipitation, etc. This phenomenon occurs in more than 99 countries, affecting about 250 million people, mostly in Africa. Two-thirds of the continent are deserts or drylands, and 73 percent of its agricultural dryland are severely or moderately degraded.

More than 30 percent of the southern African land area is arid and semi-arid and is, therefore, under severe threat from scourges of drought and desertification.

Although scientists believe that desertification is a result of climate fluctuations and atmosphereic changes, it is now generally accepted that human activities are the primary causes of desertification. The process of desertification is set-off and enhance by people’s impact on ecosystems through deforestation, overgrazing, overcultivation, population growth and irrigation.

Colonisation brought inequalities in the distribution of land. This resulted in many indigenous people being restricted to limited and often marginal land. They made up the bulk of the population but they got less land than the settler farmers. Naturally, the indigenous population has continued to grow but there has not been any corresponding increase in the size and quality of land allocated to them. These problems are particularly acute in communal areas of Tanzania, Zimbabwe and the former "homelands" of South Africa.

Increasing poverty contributes to desertification as the disadvantaged groups are forced to overexploit their environment in the short-tern, without considering the long-term effects of their actions. With poverty, people have little or no alternatives to survive their needs.

The degree of aridity is decisive. In extreme deserts with 12 arid months, vegetation is concetrated in areas with more water and better soils, such as oasis and depositional basins. A slight interference in this sensitive ecosystem can cause an irreversible loss of natural balance. In fact the more arid the climate, the greater the destruction of the natural potential of the land can be.

The southern African region’s rainfall is very unreliable. The situation has become worse since the 1991-92 and 1994 –95 droughts and this has increased the rate of degradation of land and related resources. Areas threatened by desertification generally have low rainfall (less than 400 mm per year) and over-use of natural resources. The variability of rainfall in the desert-margin zone is another cause of desertification. The high divergence of rainfall from the main increases the instability of the ecosystem and enhances the desertification process.

Depletion of forest resources is mainly due to agriculture (shifting cultivation), settlements expansion (population movements) and demand for fuelwood. Charcoal production and tsetse-fly control are localised causes of deforestation.

In the SADC region, biomass fuels are the major source of energy for rural industries such as tobacco curing, tea-drying, fish-smoking, brick-burning, and salt production. The provision of alternative sources of energy and building materials are possible solutions to the problem. In Zimbabwe, between 70,000-100,000 ha of woodland are cleared each year for agriculture. Tanzania loses between 300,000-400,000 ha of forests annually to shifting cultivation.

The reduction in ground cover by plants that accompanies desertification, accelerates soil erosion by wind and water. South Africa loses about 300-400 million tonnes of topsoil every year, and Swaziland 50,000 tonnes from gully erosion alone. Virtually all cultivated and grazed areas in the SADC region are losing soil faster than it is being formed.

When the soil is trampled and compacted by cattle, it can loose its ability to support plant growth and to hold moisture, resulting in increased evaporation and surface run-off. Poor land management practices have led to excessive soil erosion resulting in poor crop yields.