Tag: striving for a better environment

If the same crop is grown year after year, fertility of soil is lost due to utilization of same minerals again and again, thus, disturbing the soil structure, which facilitates soil erosion. Legumes are useful in rotation of crops because of having nodulated roots which harbour nitrogen fixing Rhizobium bacteria and it leaves more nitrates in the soil when the roots are left over in fields and only aerial parts of legume crops are harvested.

Vermicomposting is a method in which earthworms are used to convert the organic wastes into compost, which is a good fertilizer for plants. It increases the soil fertility. Manure is the organic matter mainly animal feces and straw. It adds nutrients (nitrogen) in the soil, which increases the soil fertility. So, the correct option is D.

Anthropogenic soil erosion is caused by removal of plant cover through over grazing, litter collection, tree felling, leaving the soil unprotected during agricultural operations. Anthropogenic factors remove green cover and expose the soil to natural agents of soil erosion i.e., water and wind. When rains fall, most of the top layer of soil is washed away, if the soil is not covered by vegetation. 

Soil pollution is caused by removal or addition of substances which decrease its productivity. It is caused by agrochemicals, industrial wastes, municipal wastes etc. It adversely affects the fertility of the soil. Pesticides, weedicides, and fertilizers are added to soil in agriculture practices to remove unwanted plants and increase the fertility of the soil. These chemicals penetrate into soil and damages the soil.

When trees are cut on a large scale land becomes barren. This results in the loss of upper soil layer due to heavy wind or flowing water leading to soil erosion. Roots of plants hold the soil particles and prevent their loss. Hence afforestation i.e. growing plants to form a soil cover prevents soil erosion. Thus the correct answer is option B.

Terracing is a process of making sloped plane into series of succesively receding flat surfaces or platforms resembling stairs, this is how erosion is minimised.

Soil erosion is the phenomenon in which the top most layer of soil gets lost, since plants have the capability of holding the soil particles together and prevent them from being eroded away

Soil pollution greatly due to use of  large amount of herbicides, pesticides. There also some more reason of soil pollution like industrial wastes are dumped into fertile soil which get polluted and also not having proper satiation. But soil erosion is not responsible for soil pollution, soil erosion is mainly due to deforestation. So B option is right.