Desertification was defined at the Rio Earth Summit in 1992 as degradation of drylands,the point at which that land no longer can be returned to a productive state. It results from complex interactions between unpredictable climate variations but primarily human activities. The term desertification was first coined by French scientists and explorer Louis Lavauden in 1927. One of the major cause of desertification is overgrazing due to the use of fences which has prevented the livestock from moving in response to availability of food. However, when used correctly, fencing is a good tool of veld management. But the core contention among all the environmental issues faced by planet Earth is Global Warming and consequent Climatic Change. In its report the Intergovernmental Panel for Climatic Change (IPCC), formed out of the Kyoto convention decades before, also said that Rise of average global temperature melts polar ice and mountain glaciers, raises sea-level and endangers coastal submersion. A decrease or nil in the total amount of rainfall in drylands result in the destruction of topsoil and vital soil nutrients needed for food production also leading to desertification. Deforestation and incorrect irrigation practices in arid areas causing salinisation can prevent plant growth which in turn triggers desertification when coinciding with drought. It also reduces the ability of land to support life, affecting wild species, domestic animals, agricultural crops and people. The reduction in plant cover that accompanies desertification leads to accelerated soil erosion by wind and water. Water is lost off the land instead of soaking into the soil to provide moisture for plants. Even plants that would normally survive droughts die. A reduction in plant cover also results in a reduction in the quantity of humus and plant nutrients in the soil, and plant production drops further.
As protective plant cover disappears, floods become more frequent and more severe. Desertification is self-reinforcing, i.e. once the process has started, conditions are set for continual deterioration. Desertification can be stopped, but unfortunately is usually brought to public attention when the process is well underway. Both individuals and governments can help to reclaim and protect their lands. Covering the dunes with large boulders or petroleum will interrupt the wind regime near the face of the dunes and prevent the sand from moving in areas of sand dunes. Shrubs and trees planted on the dune will also decrease the wind velocity and prevents much of the sand from moving. More efficient use of existing water resources and control of salinization are other effective tools for improving arid lands. On a much larger scale, a “Green Wall,” which will eventually stretch more than 5,700 kilometers in length, much longer than the famous Great Wall, is being planted in northeastern China to protect “sandy lands”— deserts believed to have been created by human activity. The World Day to Combat Desertification is celebrated every year on June 17 all over the world to highlight the urgent need to curb the process of desertification and to strengthen the visibility of this drylands issue on the international environmental agenda. The United Nations Convention to Combat Desertification (UNCCD) is the only internationally recognized, legally binding body that addresses the problem of land degradation in the drylands and which enjoys a truly universal membership of 191 countries. It plays a key role in global efforts to eradicate poverty, achieve sustainable development and reach the Millennium Development Goals, in particular with regard to the eradication of extreme poverty.The need of the hour is to treat desertification as a wake-up call and to try and take it through strengthened community participation and cooperation at all levels.