By Ezenwafor Ifeoma .v
Soil, which covers the surface of the earth, is the normal medium for plant
growth. Plants are anchored in the soil by their roots which spread in all directions
and which, by holding on to the soil, keep the plant in position. Soil is therefore the
source of food for plant, animal and man. Soil is fertile if it can supply adequate
nutrients to plants when they need them. About two-thirds of African depend on
agriculture for their livelihood and as the region's population continues to grow
rapidly, farmers are intensifying land use to meet food needs without proper
management practices and external inputs. The resulting depression of nutrients
from soil has caused crop production to stagnate or decline in many African countries
(FPRI, 1999)