Tag: soil erosion and conservation

Questions Related to soil erosion and conservation

In our country, large patches of forests are being cleared for cultivation of crops. The environmental impact of such a practice will lead to

  1. Soil erosion

  2. Soil conservation

  3. Soil pollution

  4. Soil fertility


Correct Option: A
Explanation:

Soil erosion is washing away or blowing away the top layer of the soil. Plants in the forests are big and are present near to each other. During rain or wind, forest plants prevent the top layer of soil to be cleared. These plants keep the soil intact within their roots and do not let it to blow or washed away. But when such plants are cleared, nothing stops the wind or water to blow away or wash away the top soil layer. This leads to soil erosion. 

Which one of the following erosion processes is a natural process?

  1. Geological erosion

  2. Accelerated erosion

  3. Gully erosion

  4. Rill erosion


Correct Option: A
Explanation:
New soils can be formed through the slow weathering of the parent rock material, and from the deposition of air-borne or waterborne sediments. Under normal climate conditions, and with natural ground cover, soil erosion can often balance out with the rate of soil production. This is called natural, or geological erosion. Unfortunately, these geologic processes are very slow and are often overshadowed by the activities of man.
So the correct option is 'geological erosion'.

 

Farm land tends to erode most rapidly when planted with

  1. Wheat

  2. Potato

  3. Saccharum

  4. Clover


Correct Option: C
Explanation:

Farm land tends to erode more rapidly when continuously planted with sugarcane, as sugarcane requires high moisture and organic content. As the amount of moisture and organic content decreases the top layers of soil can be easily eroded by wind or water

So, the correct answer is 'Saccharum'

The best way to check soil erosion is by providing adequate trees and

  1. Grass cover

  2. Manure

  3. Water

  4. Sand


Correct Option: A

Material produced by weathering accumulates in

  1. Sedimentary Rocks

  2. Depositional basins

  3. Basins

  4. Igneous rocks


Correct Option: B

Removal of the soil by the action of wind and water is known as 

  1. Erosion

  2. Fossilization

  3. Leaching

  4. Calcification


Correct Option: A
Explanation:

The top layer of the soil is the vital component, since all the nutrients required by plants are present in this layer. The loss of topsoil or disturbance of soil structure is known as soil erosion or land erosion. Water erosion is the removal of soil from the lands surface by running water, including runoff from melted snow and ice. Soil erosion by wind is common in dry arid regions where soil is chiefly sandy and the vegetation is very poor or even absent. Fossilization is the alteration of an organism's remains, impressions or activities by physical, biological or chemical changes retaining the original material in some form. Leaching is the process of extracting minerals from a solid by dissolving them in a liquid, either in nature or through an industrial process. Calcification is the accumulation of calcium salts.

Therefore, the correct answer is option A.

To prevent soil erosion, a farmer plants a hedge across a field. This method works because

  1. The hedge prevents the soil from direct impact of rainwater.

  2. The roots of plants prevent the soil erosion.

  3. The hedge absorbs minerals from the soil, which makes it most compact.

  4. None of the above.


Correct Option: B
Explanation:

The vetiver grass is grown as a narrow hedge row across the slope of the land that slows down rainfall runoff velocity and filters out soil particles. The vetiver hedges can block the passage of soil. They can keep topsoil on site and, over time, retard most surface erosion. Hedges of this deeply rooted perennial are capable of catching eroded soil and helping to build up terraces that stabilize the site. 

Therefore, the correct answer is option B.

Soil erosion by wind brings about the serious damage in soil by changing the__________

  1. Soil permeability

  2. Soil structure

  3. Soil texture

  4. Soil plasticity


Correct Option: C
Explanation:
  • Surface texture is the best key to wind erosion protection. Very fine soil particles are carried high into the air by the wind and transported great distances (suspension). 
  • Fine-to-medium size soil particles are lifted a short distance into the air and drop back to the soil surface, damaging crops and dislodging more soil (saltation). 
  • Larger-sized soil particles that are too large to be lifted off the ground are dislodged by the wind and roll along the soil surface (surface creep). The abrasion that results from windblown particles breaks down stable surface aggregates and further increases the soil erodibility.

Arrange the following in the descending order of their role in soil erosion
(I) Wind erosion
(ii) Chemical degradation
(iii) Physical degradation
(iv) Water erosion

  1. iv $\rightarrow$ i $\to$ ii $\to$ iii

  2. iv $\to$ ii $\to$ iii $\to$ i

  3. $\to$ ii $\to$ iii $\to$ iv

  4. iv $\to$ iii $\to$ ii $\to$ i


Correct Option: A
Explanation:

Water erosion is when the flowing water carries away the soil with it.This amounts for the largest amount of soil erosion. Wind erosion is when the blowing wind carries the soil with it. physical degradation is a gradual process of many steps beginning from structural deterioration and ending in the differential loss of finer particles through erosion. Physical degradation is a gradual process in which the soil is broken down into finer particles. Chemical degradation mainly consists of soil pollution and acidification. Thus the correct answer is option A.

Arrange the following in descending order of their role in soil erosion.
(i) Wind erosion

(ii) Chemical degradation 
(ii) Physical degradation 
(iv) Water erosion

  1. i, ii, iii, iv

  2. iv, i, ii, iii

  3. iv, iii, ii, i

  4. iv, ii, iii, i


Correct Option: B
Explanation:

Soil erosion is the process of wearing of upper layer of soil by the natural physical forces such as water and wind or by farming activities. Water erosion and wind erosion are the two major physical forces which play an important role in soil erosion. The farming activities include chemical and physical degradation. Use of pesticides leads to soil erosion. Physical degradation such as cutting of trees leads to soil erosion.

Thus, the correct answer is 'iv, i, ii, iii.'