(introduction...)

In Africa many soils can become bad.
Why?
The sun, the rain and the wind change the soil a great deal.
In Africa the rains are often very heavy.
After the rains the heat is very great.
Great heat after heavy rains ruins the soil: the humus is quickly destroyed.
The wind too ruins the soil So we have to protect the soil from sun, rain and wind by stopping the water from flowing away; by covering the soil.

· If you always farm the same field, the plants will take all the mineral salts out of the soil.

You must let the earth rest by fallows; by crop rotation; by land- use allocation.