The water holding capacity is the highest in clayey soil

A gardener often gently digs up the soil around the roots of garden plants or herbs for following reasons
(i) It enables easy root growth.
(ii) For easier percolation of water.
(iii) For aerating the soil enabling air to get into deeper layers of soil.
(iv) For removing the weeds.

In dense forests, the tree cover (canopy) prevents rainwater from directly falling on the ground/soil. Also roots of the vegetation bind the soil particles and hold them together. As a result, soil erosion is minimised. But in barren, open fields, the soil is exposed to the falling rain. The soil particles become loose due to the impact of raindrops and the flow of water carries them away. The flowing water further erodes the soil surface aggravating erosion.

(a) It is because these substances pollute the soil. They also kill the organisms living in the soil.
(b) Substances which pollute the soil are a number of waste products, chemicals, pesticides, polythene bags and plastics.
(c) Alertness, responsibility and ecofriendly nature

Soil in field A is sandy soil while in field B soil is clayey soil which has low percolation rate and water-logging is seen. Since, paddy requires lot of standing water, therefore it is grown in field B.

Labelled sketch of the cross-section of soil is

The farmer can convert acidic soil into neutral soil by adding a small quantity of quicklime or slaked lime solution to the soil

No, soil from a field cannot be used to make toys. In order to make toys, the soil should be clayey.

Polythene bags and plastics pollute the soil as they kill the organisms living in the soil. That's why, it is necessary to ban the use of polythene bags and plastics

The term shimmering means that the air shines with a slightly shaking light.

The absorption percentage of water can be calculated by the formula given below
Percentage of water absorb
\(\frac { amount\quad of\quad water\quad absorted(in\quad ml) }{ amount\quad of\quad soil(in\quad gm) } x100\)

Ans. Yes, soil erosion does not occur easily where the land is covered by vegetation (trees and other plants). It occurs easily in those areas of land which are not covered by vegetation (trees and other plants) or have very little vegetation. If there is vegetation on land,
(i) then the roots of vegetation growing in the soil bind the particles of topsoil firmly. Due to this, the blowing wind and flowing rainwater are not able to carry away topsoil and hence soil erosion does not occur.
(ii) then much of the falling rain hits the trees and plants before it hits the soil. In this way, the cover of vegetation softens the effect of heavy rains on the soil

The contamination of soil with waste materials especially used polythene bags and plastics, pesticides, fertilisers, acid rain industrial chemical wastes, etc., is called soil pollution
Pesticides are the poisonous chemical substances which are sprayed on standing crops to save them from the harmful insects and diseases. Some of these pesticides also mix up with the soil in the fields and pollute it. The grains, fruits and vegetables grown in this polluted soil contain pesticides. When we eat such contaminated grains, fruits or vegetables, the pesticides present in them damage our health also.