Environmental Studies · Geography

Deforestation and Land Degradation

2,619 Questions

Deforestation and land degradation address the environmental impacts of human activities on natural ecosystems. Key areas include soil erosion, forest fires, and the consequences of overgrazing. These subjects frequently appear in the geography and environmental science sections of competitive exams.

Causes of deforestationForest fires consequencesSoil erosion factorsDesertification impactsAgroforestry benefitsReforestation advantages

Deforestation and Land Degradation Questions

Multiple choice general knowledge the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Soil erosion can be prevented by _________.

  1. increasing bird population

  2. afforestation

  3. removal of vegetation

  4. overgrazing
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Afforestation, or the planting of trees, creates a root network that stabilizes the soil and reduces the impact of rain and wind. The other options either promote erosion or have no direct effect on soil stability.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Which is the main causative factor of desertification

  1. Developmental activities

  2. Tourism

  3. Overgrazing

  4. Irrigated agriculture
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Overgrazing is an important reason for desertification. Overgrazing denudes the soil of plant cover. Trampling by cattle decreases soil porosity. The exposed hardened soil undergoes erosion by wind and water. Wind erosion is more common, where drought conditions prevail for long periods. It causes desertification or conversion of once fertile land into desert.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Soil erosion can be prevented by

  1. Raising forests

  2. Deforestation

  3. Excessive use of fertilizer

  4. Overgrazing by animals
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Soil erosion is the process of washing and wearing away of the top fertile soil due to the physical pressure and force of water, wind or other farming activities like tilling, ploughing etc.
The soil can be prevented from getting eroded by planting and raising more trees as the roots of the trees hold the soil tightly and prevents it from getting washed away.
Deforestation means cutting down of trees and more we cut down the trees more the soil will be left loose and easily washed away and get eroded.
Excessive use of fertilizers can leave the soil degraded, loose, dry and barren and more vulnerable and easier to get eroded.
Overgrazing by animals can leave the soil loose, dry and barren totally exposed to get washed away and get eroded completely.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Which of the following is not the function of forest? 

  1. It is used to make paper.

  2. Resin, gum and drugs are obtained.

  3. Controls flood.

  4. Causes soil erosion.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Forests and trees make an essential contribution to food security by helping to maintain the environmental conditions needed for agricultural production. They stabilize the soil, prevent erosion, enhance the land's capacity to store water and moderate air and soil temperatures.

Therefore, the correct answer is option D.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Soil erosion can be prevented by

  1. Terrace farming

  2. Intensive cropping

  3. Deforestation

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Soil erosion can be prevented by:
(i) Intensive cropping means growing of more crops in the same fields and not leaving them unused. If the fields remain covered with crops throughout the year, top soil will not be exposed to winds or rains. Thus, no soil erosion will occur.
(ii) In hilly regions, small fields are formed in the form of steps or terraces for cultivation of crops. Such a farming in hilly regions Is called terrace farming. This technique reduces the flow of rain water down the slopes of hills. Moreover, eroded soil from upper regions of hills gets deposited in lower terraces. In this way, soil erosion can be prevented in hilly regions.
So, the correct answer is 'Both A and B'.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Soil erosion is caused due to

  1. Strong winds

  2. Heavy rains

  3. Keeping the fields fallow for a long time

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Causes of soil erosion are:
(i) Uncovered loose soil gets eroded when it is exposed to strong winds. The winds carry away the soil particles to other places,
(ii) When rain falls on the unprotected top soil, rain water washes it down into the streams and rivers etc.
(iii) Farmers loosen the top soil of the agricultural fields either for cultivation or for removing the weeds. Sometimes due to certain reasons, these agricultural fields remain fallow (not cultivated) for a long time. Top loosened soil of these agricultural fields, thus, becomes prone to erosion by winds or rains.
So, the correct answer is 'All of the above'.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Deforestation causes

  1. Soil erosion

  2. Soil pollution

  3. Water pollution

  4. Noise pollution
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In deforestation, there is the cutting or the removal of plants. The roots of the plants allow the soil to be held due to the presence of water. Due to deforestation, the water present in the soil gets evaporated resulting in a barren land. This barren land is prone to soil erosion which results in the loss of the upper layer of the soil. When new trees are planted, the soil erosion can be prevented. 

Thus, the correct answer is option A. 

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

The effect of rainfall over the soil which is covered by vegetation and the effect over the soil left bare after harvesting, respectively, would be

  1. No change in both cases

  2. No soil erosion and rapid soil erosion

  3. Rapid soil erosion and no soil erosion

  4. Soil erosion in both cases
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Roots of plants hold the soil particles and prevent their loss. Hence vegetation prevents soil erosion. When vegetation is lost and soil is kept barren after harvesting there is soil erosion due to the loss of upper soil layer caused by heavy wind or flowing water. Thus the correct answer is option B.  

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Main cause of soil erosion

  1. Afforestation

  2. Less rains

  3. Thinning of ozone layer

  4. Deforestation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In deforestation, there is the cutting or the removal of plants. The roots of the plants allow the soil to be held due to the presence of water. Due to deforestation, the water present in the soil gets evaporated resulting in a barren land. This barren land is prone to soil erosion which results in the loss of the upper layer of the soil. When new trees are planted, the soil erosion can be prevented. 

Thus, the correct answer is option D. 

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

What happen when rain falls on soil without vegetational cover?

  1. Rain water percolates into soil efficiently.

  2. Rain water cause loss of surface soil.

  3. Rain water leads to fertility of the soil.

  4. Does not cause any changes in the soil
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During heavy rainfall, trees act as a natural absorber. They prevent soil erosion, thereby reducing sediments going into rivers and increasing water absorption into the ground. But when the soil is without vegetational cover rainwater carries away the soil and causes its loss. Thus the correct answer is option B.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Which of the following should be increased to prevent soil erosion?

  1. Flow of water

  2. Green areas

  3. Deforestation

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Trees keep the soil particles bound together. They have roots that extend deep in the soil. The roots of trees hold the soil particles tightly together and prevent their erosion and washing away due to factors like wind, water, rains etc.

So, option B is the correct answer.

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

What prevents soil erosion?

  1. Allowing herbivorous animals to graze excessively

  2. Growing plants to form the soil cover

  3. Increasing fertility

  4. Making the land sloppy
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • Soil erosion is the loss of the fertile soil due to an absence of plants which can hold the soil. 
  • The roots of the plants allow the soil to be held due to the presence of water. In deforestation, there is the cutting or the removal of plants. 
  • Due to which the water present in the soil gets evaporated resulting in a barren land. 
  • This barren land is prone to soil erosion which results in the loss of the upper layer of the soil.

Thus, the correct answer is option B. 

Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil soil erosion and conservation

Soil erosion can be reduced by

  1. Grazing cattle

  2. Deforestation

  3. Using renewable resources

  4. Contour ploughing

  5. Increasing biodiversity
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A. Grazing cattle can promote soil erosion because as the cattle eat the vegetation, the soil particles loosen and can be easily carried away by wind, water etc.
B. Deforestation leads to soil erosion because roots of the plants held the soil particles tightly and if there will be no trees, the soil particles will be loosened and can be easily carried away by wind or water.
C. Using renewable resources has no effect on soil erosion as renewable sources are the sources that can be replenished naturally over a period of time.
D. Contour ploughing is the ploughing of land according to its contour or slope to prevent soil erosion.
E. Increasing biodiversity will promote soil erosion as more organisms will be there which will feed on vegetation and this will cause the same effect as that of grazing cattle.
Hence, soil erosion can be reduced by Contour Ploughing.
So, the correct answer is 'Contour ploughing'.
Multiple choice biology the soil soil erosion (geo) soil erosion, soil conservation and uses of soil 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
Reveal answer Fill a bubble to check yourself
A Correct answer
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.