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Salinity must be monitored and necessary measures must be taken immediately for a
sustainable agriculture. This is a necessity for both conserving environment and
agricultural production and sustainable agricultural production.
Figure 10.2. Distribution of Soil Salinity
Source: AQUASTAT, 2012
Soil salinization is a problem in 14 countries in Africa. The situation is of
particular concern in Morocco, Nigeria and Sudan, where the area salinized by irrigation
exceeds 100 thousand ha although less so in Kenya, Tunisia and United Republic of
Tanzania. Salinization also requires monitoring in; Djibouti, Gambia and Mozambique,
where soils are naturally saline; Namibia; Niger, where 350 ha have been abandoned
and others risk being so shortly; Somalia; and Zimbabwe. Finally, Egypt has controlled
its salinization since the 1970’s on a large part of its irrigation schemes through the
installation of drainage systems (Annex 9).
Other major environmental problems related to irrigation in Africa are: (i)
erosion and its consequences and silting up or sedimentation of water bodies, dams and
canals (ten countries); (ii) proliferation of aquatic vegetation (six countries); and (iii) the
drying up or the risk of drying up of wetlands (four countries). An estimated 70% to