4.
What are the causes of soil erosion? Mention any two methods of soil
conservation
Answers
Answer:
Explanation:
Various agents, like wind, water, deforestation, overgrazing by cattle, etc., cause soil erosion. The various factors of soil erosion are:
1. Wind
When strong winds blow, the topsoil along with the organic matter is carried away by the wind. This happens more often when the land is not covered with grass or plants. Such conditions are very common in desert and semi-desert regions where strong winds blow very frequently.
2. Water
When it rains in the hilly areas, the soil gets washed away towards the plains. The running water deposits the mineral-rich soil in the riverbed and over the years this deposition of soil can change the course of the river. This can lead to floods which cause the destruction of life and property. Water erosion leads to loss of agriculture potential.
3. Overgrazing
When cattle are allowed to graze on the same field repeatedly, all the available grass, including the roots are eaten by them. This makes the topsoil vulnerable to wind and flowing water, leading to soil erosion.
4. Deforestation
Humans have taken land from the forest to cultivate in order to feed the ever-increasing population and to build houses, industries, etc. Cutting down of trees on a large scale for these purposes is deforestation. The roots of trees hold the soil together, thus preventing the soil from getting uprooted. When large areas of the forest are cleared, the topsoil gets eroded by wind and flowing water.
Soil conservation
Prevention of soil erosion is also called conservation of soil. The soil erosion can be prevented by the following ways:
1. Afforestation
Planting new trees and plants is afforestation. We live because plants live. If the plants die, all living things will also die. Thus, whenever trees are cut down new trees should be planted. Planting trees in hilly areas are most effective for conservation.
2. Crop Rotation
Between harvesting one crop and planting the next crop, the fields lie bare; there is a time period when the farmland does not have any crops. During this period, the farmer either grows grass or grows other crops to prevent soil from erosion. This helps the soil to regain the lost minerals.
3. Terrace Farming
In hilly areas, farming is done by cutting steps on the slopes of the hills. This slows down the flow of water and soil removed from one step is deposited on the next step. Thus, the soil is never completely lost. This is terrace farming.
4. Building Dams
Dams are built to prevent floods, which not only damage the crops but also wash away the topsoil.
5. Shelterbelts
The cover of plants and trees around the field also breaks the speed of strong winds and protects the soil from being blown away.
6. Embankments
Bib strong structure called embankments along the banks of the river can protect fields from the floods. These embankments prevent the fast overflowing rivers and rainwater from washing away a huge amount of rich fertile soil.
7. Van Mahotsav
It is an annual tree planting festival started by the Government of India. The aim of this programme is to create awareness about the need for conservation of forest and soil.
Answer:
causes- deforestation
methods of conservation- afforestation