Drought and desertification occur when:
- there is a climatic predisposition to drought, e.g. in certain arid and semi-arid areas worldwide;
- a high population density results in a greater need for resources;
- a region is dependent on agricultural activity for its economy, and is thus reliant on water and soil resources.
Desertification is accelerated by migratory movements and an exodus from rural areas, which has socioeconomic and political consequences and may aggravate tensions. This constant pressure in fact further degrades the environment.
The impact of this migration on natural resources is two-fold, affecting both the area of origin and the area of destination.
In the area of origin
People leave their area of origin because it has become degraded and unfruitful; these areas are often fragile, overexploited and prone to wind erosion. Moreover, the instability of techniques used to work the ground, poor levels of fertility, irrigation, etc. often do not allow for the generation of a surplus which could be reinvested to improve conditions. Indeed, the mass departure of men puts rural women in a difficult situation, as they must assume a new role for which they are often not prepared.
In the area of destination
The majority of immigrants arriving in destination areas practice intensive farming methods. Fallow periods are reduced, which in turn prevents fields from regenerating to full productive capacity. The arrival of migrants with other farming practices, such as the introduction of cotton production in Mali, has accelerated the pace of deforestation in this area. Other migrants practice intensive poaching in protected reserves, which leads to an imbalance of fauna in the locality.
Thus, poverty ultimately contributes to desertification which, in turn, generates more poverty.
In order to keep pace with global economic pressures, the ground in many regions has been overused and, generally, the most impoverished citizens are the worst affected.