ABSTRACT
Desertification is defined as “land degradation in arid, semiarid, and dry subhumid areas resulting mainly from adverse human impact” (UNEP, 1992). Desertification can also occur in cold and humid climates, especially under ecologically sensitive ecoregions (Arnalds et al., 2001). There are two important points in this definition. One, desertification addresses the problem of land rather than soil. The term land is broad-based and refers to an ecosystem that comprises climate, vegetation, soil, terrain, and hydrology. Two, desertification addresses the problem originating from adverse human impact or anthropogenic activities. Therefore, drought and other natural events merely exacerbate the problem but are not a driving factor in the process of desertification per se. The effects from the dust bowl of the 1930s were exacerbated by excessive tillage.
