The semiarid zone of the Democratic Republic of the Sudan encompasses about half of the surface area of the country. During the long drought phase in the Sudan, in which a chronic lack of food, fodder, and water prevailed, both humans and animals proved to what extent biological adaptation to sustain food and water deficits could go. Land-use systems in the Sudan have changed from pastoralism combined with small-hold shifting cultivation to sedentary, non-rotational farming, partly for subsistence and partly for cash. In the Sudan, under the present disastrous economic conditions and the ever-increasing human and livestock pressure on land, the imposition of adequate protective and remedial measures seems almost impossible. Soil erosion and the deterioration of the land's productivity is shown by the decrease in millet yields in the Sudan. Natural conditions in the semiarid zone of the Sudan entail a certain degree of susceptibility to ecological hazards.