Mineral Riches in the Soil Questions in English

(C) Soil erosion is the removal of the top layer of soil by natural forces like wind and water.
Raising forests (afforestation) is an effective method to prevent soil erosion because the roots of trees bind the soil particles together,preventing them from being washed or blown away.
Deforestation and overgrazing remove the protective vegetation cover,making the soil more susceptible to erosion.
Excessive use of fertilizers can degrade soil quality but does not directly prevent physical erosion.

(D) When rain falls on soil without vegetational cover,there are no roots to hold the soil particles together.
As a result,the force of the falling raindrops and the flow of water wash away the top layer of the soil,which is rich in nutrients.
This process is known as soil erosion,leading to the loss of fertile surface soil.

(D) Soil is formed through the process of weathering of rocks over a long period of time.
During this process,the large rocks are broken down into smaller particles by physical,chemical,and biological factors.
Since minerals are inherent components of rocks,the parent rock serves as the primary and major source of minerals found in the soil.
Therefore,the correct option is $D$.

(B) The topsoil is the uppermost layer of the soil.
It is rich in humus,which is the organic matter formed by the decomposition of dead plants and animals.
It also contains various living organisms (such as bacteria,fungi,earthworms,and insects) and soil particles (sand,silt,and clay).
Therefore,topsoil is a mixture of humus,living organisms,and soil particles.

(D) Soil formation is a slow process involving the weathering of rocks.
$1$. The sun causes rocks to expand and contract,leading to cracks.
$2$. Water enters these cracks,freezes,and expands,breaking the rocks into smaller pieces.
$3$. Wind carries abrasive particles that wear down rocks over time.
$4$. Polythene bags are non-biodegradable synthetic materials that do not contribute to the natural weathering of rocks or the formation of soil; instead,they pollute the soil and hinder its natural processes.