Every year, 12 million hectares of land become useless for cultivation, as the problem of desertification spreads out around the globe. This year is officially the International Year of Deserts and Desertification, and June 17 is World Day to Combat Desertification and Drought.

Human activities and climatic variations can rapidly change productive veld into a barren desert landscape, and careful land management is especially necessary in semi-arid areas. These are defined as areas where between 450 and 600mm of rain falls annually, and most of South Africa falls into this category.Worldwide, desertification affects 20 percent of the population, producing increased poverty and declining plant and animal production. SciDevNet reports that the largest single cause of desertification worldwide is the overgrazing of pastures, which is sometimes linked to the stopping of widespread nomadic stock movements.

Through overgrazing and soil erosion, South Africa is estimated to lose 300-400 million tonnes of soil annually. Soil erosion rapidly accelerates once started, with increased run off from rainfall carrying off more and more soil.This year's theme is "Desertification: a threat to humanity", and in March the department of environmental affairs earmarked five million rand for rehabilitating the soil in the Sekhukhune area of the Limpopo Province near Burgersfort. Overutilisation of natural resources in the area has resulted in a significant amount of silt from Sekhukhuneland being washed into the Olifants River.