ABSTRACT
Food production per capita in Sub-Saharan Africa is decreasing and the natural resource base is degrading. Already there is evidence that soil degradation has reduced crop yields in West Africa. This is due mainly to rapid population growth rate accompanied by salinity of lands, reduced fallowing, deforestation and erosion. Most countries in Sub-Saharan Africa, including Togo, are experiencing declining levels of food self-sufficiency. In 1965, for example, these countries were 107 per cent self-sufficient, but selfsufficiency declined to 103 per cent in 1975 and to only 93 per cent in 1985 (Rask, 1992). The population growth rate ranged between 2.5 per cent and 4.4 per cent between 1970 and 1975, for example, while crop production grew at a rate of only 1.7 per cent on average. Loss of self-sufficiency coincided with a period of declining per capita incomes and stable per capita food consumption. Hence poverty is the main cause of food insecurity in Africa, with the small subsistence farmers experiencing the lowest labour productivity. To ensure sustainable agricultural production and increase in incomes (and agricultural labour productivity), at least in the short run, it is important to improve soil fertility through the use of external nutrients such as fertilizers (Teboh, 1994).
