Population society and desertification

The hot deserts of the world, the areas of little or no vegetation, are natural phenomena. Desertification, the aggravation or intensification of such conditions, is a human phenomenon, arising most commonly from society's search for secure livelihoods in dry environments. In most instances, this search proves successful. In others, it involves destructive processes in which the productive base deteriorates and the social system is imperilled. Unlike drought, which is usually a short-term diminution in available moisture (l-5 years), the physical processes involved in desertification are long-term, chronic, and pervasive. Dune and sand encroachment, degradation of vegetative cover and resources, soil erosion, and, where irrigation is used, waterlogging and salinization. Although distinct from short-term fluctuations, these long-term processes are intimately affected by them. Wind, storms, and drought greatly accelerate chronic destructive conditions.