Answer to Question 1
Desertification refers to the formation and expansion of degraded areas of soil and vegetation cover in arid, semiarid, and seasonally dry areas, caused by climatic variations and human activities. Erosion results in the loss of water-holding capacity. Water-holding capacity is determined by plant cover, humus, and the vegetative or litter mat; these things will slow the movement of water and allow for infiltration. Erosion removes topsoil and humus. When these are removed the ability to hold water is reduced and desertification results.
Answer to Question 2
Plastic items are likely to include plastic bags (shopping and produce), water and soda bottles, shampoo and liquid soap/detergent containers, shrink wrap and other packaging material, and disposable pens, razors, and so on.
Plastic bags can be reused, as can water bottles. Shampoo and liquid soaps/detergents can be purchased in larger containers, and reusable pens and razors can be purchased. Rather than accepting a plastic bag to hold your purchases, a canvas bag could be used.
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