This question was popular among the candidates. Many of the candidates who answered the question performed poorly. Some of the candidates were not able to mention the areas where lateritic soil were found. The areas of distribution of lateritic soil include:
- the Zaire Basin;
- the humid areas of West Africa;
- the Amazon Basin;
- the South Eastern Coast of North America;
- the Eastern Coast of Australia.
Some of the candidates who answered the question could not write a good account on the formation of lateritic soil. Lateritic soil is formed through the following processes:
- there is a contrasting weting and drying of the land amist a constant high
temperature;
- the rain water dissolves soluble minerals leaving behind iron and alluminium;
- the dissolved minerals are leached downwards;
- the water is drawn back to the surface during the dry season by capillary action,
bringing back most of the dissolved minerals in insoluble form;
- this insoluble mineral forms hard pans when the soil dries up;
- the concentration of iron and alluminium compounds gives the reddish coloration
of the soil.
Quite a good number of the candidates who answered the question were able to write on
the characteristics of lateritic soil.
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