(a) Distinguish between deflation and abrasion (b) Using specific examples, describe one landform produced by each of the processes ill (a) above (c) Give any two reasons why wind erosion is more active in arid than in humid regions
Explanation
(a) The differences between deflation and abrasion are as follows; Deflation involves the lifting and blowing away of loose materials from the ground. Such unconsolidated sands and pebbles may be carried in the air or rolled along the ground depending on the size while abrasion involves the sand blasting of rock surfaces by winds when they hurl sand particles against them. The effect of sand blasting results in rock surfaces being scratched, polished and worn away. (b) One landform produced by deflation is the deflation hollows. Deflation results in the lowering of the land surface gradually until large depressions are formed called deflation hollows. One landform produced by abrasion is the Rock pedestals. The sand blasting effect of winds against any projecting rock masses wears back the soft layers so that an irregular edge is formed on the alternate bands of hard and soft rocks. Grooves and hollows are cut in the rock surfaces, carving them into fantastic pillars called rock pedestals. (c) Two reasons why wind erosion is more active in arid than in humid regions. (i) In arid regions like the desert, wind erosion is more active because of absence of vegetation. Absence of vegetation enables the-wind to move at high speed thereby causing wind erosion. (ii) Absence of moisture to bind the soil particles together. Since there is no moisture, the soil particles are loosely held hence they can easily be carried away by winds.