The answer is; desertification
Topsoil is usually the riches soil in terms of nutrient is important in support of plant vegetation. It is rich because it contains humus and other decomposed materials that recycle nutrients. When the topsoil is washed away, the local region becomes barren in that it cannot support vegetation. This causes the area to turn into a desert.
Answer:
A=T is the answer ..............
Answer:
A. (exponential) population
