Question

differences between the followings are 1. soil erosion and soil conservation 2. afforestation and deforestation 3. bands and shelter belts 4. topsoil and Bedrock 5. soil erosion by wind and soil erosion by water

Answer 1

2 afforestation means planting the trees deforestation means cutting down the trees

Answer 2

Soil erosion is the displacement of the upper layer of soil, one form of soil degradation. A low level of erosion of soil is a naturally occurring process on all land. The agents of soil erosion are water and wind, each contributing a significant amount of soil loss each year. Soil erosion may be a slow process that continues relatively unnoticed, or it may occur at an alarming rate causing a serious loss of topsoil. The loss of soil from farmland may be reflected in reduced crop production potential, lower surface water quality and damaged drainage networks.
Afforestation is the establishment of a forest or stand of trees (forestation) in an area where there was no previous tree cover.[1]
1. Biological methods: It includes the use of plant of vegetation cover. 

       (i) Agronomic practices: It includes natural protection by growing vegetation in a   manner that reduces soil loss. These are: 

(a) Contour farming: In which preparation of fields with alternate furrows and ridges to        reduce water flow. Ridges at the same level are known as contour. On slopes, however, this type of farming is coupled with terracing. 

(b) Mulching: It is effective against wind as well as waster erosion. Some such plants as maize stalks, cotton stalks etc.., are used as a 'mulch' (a protective layer formed by the stubble). Mulches reduce soil moisture evaporation and increase amount of soil moisture by addition of organic matter to soil. 

(c) Crop rotation: It decreases soil loss and preserves the productivity of land. 

(d) Strip cropping: It involves the planting of crop in rows or strips to check flow of water