This question was fairly attempted by the candidates. In 2(a)(i-ii), majority of the candidates were able to state the reason why more food and firewood are needed in most parts of West Africa, and state the causes of soil erosion. Although majority of the candidates could not explain the term overgrazing as required in 2(a)(iii – iv).
Also, in 2(b) most of the candidates could not explain how the use of the device (gas cooker) could help check deforestation. Further to this, majority of them could neither name the parts of the disc plough nor give a reason why disc ploughs are widely used in the forest regions of West Africa as required in 2 c(i – ii)
The expected answers include:
- Explanation of overgrazing
- Overgrazing is the excessive removal of vegetative cover of pasture
rangeland through grazing
- leading to the exposure of the land to agents of erosion.
(b) Explanation why the use of cooking device could help check deforestation
- The cooking device doses not use wood or charcoal to generate heat needed
for cooking,
- hence no need for the harvesting of firewood (deforestation).
(c)(i) Name of parts labelled I,II and III
I. Beam
II. Disc scraper
III. Furrow wheel
(ii) Reasons for using disc plough in the rain forest regions of West Africa.
- Disc ploughs can work on hard soil conditions where penetration is difficult
- Disc ploughs do not completely turn over soil slices, so grass turfs which
help to protect the soil from erosion are left on the soil surface
- Disc ploughs can roll over hidden rocks or stumps
- It works better in sticky soils due to the presence of scrapers that clean attached soil
- Can make deep cut into the soil |
