Desertification is considered today as a major threat of land degradation in Mediterranean countries. More than one third of Greece is at a high risk of desertification or already desertified. Desertification as a natural process depends on many factors (physical, environmental, human) that act alone or interact with each other. The main process of desertification is soil erosion, which is most likely in degraded hilly areas. Erosion result in drastic reduction in the depth of the soil and thus the available water for plant growth, fertility and productivity of soil and vegetation. Also other important processes of desertification is the salinization of soils observed especially in low-lying coastal areas is accompanied by over-exploitation and degradation of groundwater. Desertification in addition to the severe effects of the natural environment, adversely affects the economy and society in a region, after degrading natural resources, reduces the productivity of a site and thus farmers' incomes, leading to population movements in other areas with more features employment.

Depending on the intensity of action of the processes of desertification, soil degradation can be reversible, meaning that will be able to recover if one or more of the desertification processes eliminated, or if irreversible degradation is very high (reducing soil depth greater than a critical value ). Protection of natural resources, an area of desertification requires detailed study and inventory of all the factors that cause and taking any necessary technical and institutional measures for the rational management and protection.

Source: Desertification - Problems and Measures - Konstantinos Kosmas, Agricultural University of Athens