Soil – The upper softest layer of the earth in which plants grow is called soil.
Soil is the most valuable resource on the earth.
Soil not only contains metals and minerals in its layers but it also supports life on the earth.
It grows plants the food-producers, supports animals and provides food.
Most of our basic needs for food, shelter and clothing are fulfilled from land or soil.
Formation of soil
Soil is formed by the weathering and breaking of rocks.
The wind, water and living beings cause the rocks to break.
Due to cooling, heating and drying for the millions of years, the rocks crack and break up into fine pieces to form soil.
The process of soil formation is a slow, long and continuous process.
The quality of soil is an asset of a nation.
It adds wealth to the country.
The countries which do not have quality soil have to depend on other countries for their basic needs.
Uses of Soil
There are various uses of soil.
All living beings depend on soil because their basic needs are fulfilled through the soil.
We get food, cloth, shelter, medicines, and water-the basic needs of life system from soil.
Forests which grow on soil bring rain and support various plant and animal activities
Large deposits of metals and minerals are present in the soil.
Micro organisms present in soil make it fertile and help in maintaining the ecosystem.
Soil is also used for making bricks, pots and porcelain.
Soil also stores water under the ground.
This water is used for drinking and other purposes.
Soil erosion – The process of carrying away of the top fertile layer of soil from one place to another by water, wind or human activities is called soil erosion.
Agents of Soil Erosion
Natural Agents
Water –
River and rainwater cause soil erosion.
When it rains, the top soil from the hills washes down to the rivers and plains.
The running water deposits the mineral rich soil in river bed.
During floods, the rivers get flooded and deposit the soil on another piece of land
Wind–
In nature, strong winds blow the top soil from one place to another, thus causing soil erosion. This happens more often, when land is not covered with grass or plants.
Erosion by wind is a common phenomenon in dry regions such as deserts
Human Activities
Deforestation – Cutting down trees in large number are called deforestation.
It is the cutting down of trees in large numbers.
Man has cleared large areas of forests for his requirement of wood, living space etc.
This results in soil erosion
Overgrazing by Cattle –
When animals reared by humans are left to graze on the same piece of land year after year, the land becomes bare.
This results in soil erosion.
Ploughing of Hill Sides –
This loosens the soil and increases soil erosion.
In plains, after harvesting the crop, the soil lies bare for some time which helps the wind to blow away the soil.
Soil conservation – Process of protecting soil from erosion is called soil conservation.
Man is constantly damaging the soil.
Thousand tons of soil is carried away by wind or water due to the deforestation.
The desert land is spreading speedily.
The careful protection of the soil or to check soil erosion is called soil conservation.
Different methods are adopted to check the soil erosion.
- Afforestation – Planting trees in large numbers are called Afforestation.
Trees should be planted in large numbers.
Trees slow down the wind and prevent it from blowing away the soil.
Planting grasses on hill sides also helps to stop water from carrying away the soil.
- Growing suitable crops –
The farmland remains bare when crops are harvested.
Farmer can grow seasonal vegetables and pulses, as cover crops to protect the soil until the next crop is planted.
These seasonal plants also increase the fertility of the soil by adding nutrients to it.
- Terrace farming – Farming done in the steps on hills slopes is called terrace farming.
This method should be adopted in the hilly areas.
In this method of farming the slope is cut into steps or terraces.
Soil eroded from one step gets deposited on the next.
This reduces soil erosion.
- More trees should be grown at slopes of mountains.
- Overgrazing by the cattle should be prevented.
- Strong embankments along river banks reduce soil erosion.
- Proper use of fertilizers reduces the infertility of soil.
