Soil Erosion in India: Causes, Effects and Prevention

Table of Contents

• What is Soil Erosion?
• What are the Main Causes of Soil Erosion?
  • Natural Causes
  • Human Causes
• What are the Effects of Soil Erosion in Agriculture?
• What are the Remedial Strategies for Prevention of Soil Erosion?
  • Biological Measures
  • Mechanical Measures
• What are the Government Initiatives to Reduce Soil Erosion?

What is Soil Erosion?

Soil erosion is the detachment of soil particles from one place to another place due to some natural and human causes. In soil erosion, the topmost layer washes away to faraway lands, rivers and valleys. The degraded soil loses its quality and structure, so it can be eroded more easily. Soil erosion occurs mainly on steep slopes with heavy rainfall in states like Assam, Manipur and Western Ghats. It also occurs in Maharashtra, Andhra Pradesh and Tamil Nadu. Soil compaction, loss of soil structure, low organic matter, poor internal drainage and soil acidity are some other problems that lead to soil erosion.

What are the Main Causes of Soil Erosion?

Natural Causes

Heavy Rainfall: India faces different climatic conditions all over the year. In some places where very heavy rainfall occurs, it carries away the soil nutrients and quality, which leads to soil erosion, especially in hilly areas or sloping terrains.

Wind: Soil erosion occurs mainly in less vegetative places, particularly in desert and semi-desert regions where strong breezes are very common. The small and dry particles of soil are carried away by the wind and deposited somewhere else. This wind washing the topsoil is known as wind erosion, which is a natural cause of soil erosion.

Soil Erodibility: Some soils are more prone to erosion than others, and factors like organic matter content, structure, texture and permeability affect soil erodibility more.

Local Climate and Vegetation Loss: Local climate is one of the reasons for soil erosion. It usually occurs due to sudden weather changes. Also, a good vegetative area acts as a shield between soil and drops of rain and breaks down the wind before it can reach the soil. So, the loss of vegetation is also a reason for soil erosion.

Human Causes

Mining: Mining is one of the major human causes of soil erosion. It removes the top layer of soil and can cause the loss of soil structure, and the compacted soil is more prone to erosion. It also leaves heavy metals and sediments near water bodies, reducing the water quality.

Deforestation: Deforestation is the leading cause of soil erosion as the cutting of trees leads to the detachment of the roots, which causes the loss of soil structure. Trees shield the soil from heavy rainfall and maintain soil temperature, which reduces evaporation. Deforestation leads to excessive soil erosion, which increases runoff.

Shifting Agriculture: Another significant human cause of soil erosion is shifting agriculture. This practice involves temporary cultivation of land, followed by abandonment to allow it to revert to its natural state. However, this process leads to the loss of soil structure and nutrients, ultimately degrading the soil quality.

What are the Effects of Soil Erosion in Agriculture?

Soil erosion has a massive impact on agriculture as the most fertile soil loses its richness, thus decreasing soil productivity. Here are some significant impacts of soil erosion on agriculture:

Land Degradation

The two types of natural soil erosion, water and wind erosion, are the major causes of land degradation. Around 75 billion tons of soil is eroded yearly, approximately 13-40 times faster than the natural rate of erosion. Around 40% of soil is degraded in the world.

Water Pollution

Water pollution is a serious cause of soil erosion. The eroded soil has pesticides, heavy metals, and fertilizers, which mix with water and cause water pollution. It is a threat to aquatic life forms and destroys marine and freshwater habitats.

Dust Pollution

Dust particles during wind erosion mix with toxic chemicals such as pesticides or petroleum fuels, causing breathing problems when inhaled.

Infrastructural Destruction

Soil erosion also affects dams, drainages, and embankments. It reduces their operational lifetime and efficiency.

Reduced Soil Fertility

Topsoil, the most fertile layer of soil, is crucial for agriculture. It's rich in organic matter, nutrients, and microorganisms that are essential for plant growth. However, soil erosion can strip away this vital layer, leading to a reduction in soil fertility, changes in soil structure, and pH imbalance, all of which can hinder crop growth.

Increased Pest Problem

During soil erosion, the reduced nutrient content weakens the soil, making it more vulnerable to pest infestations.

What are the Remedial Strategies for Prevention of Soil Erosion?

There are two types of preventive measures to control soil erosion. Let's discuss each in detail.

Biological Measures

Strip Cropping: Strip cropping involves planting of erosion-permitting crops (jowar, bajra, maize) with erosion-checking close-growing crops (grasses, pulses). They conserve soil moisture and reduce soil erosion by protecting the natural structure and organic matter in the unploughed areas.

Crop Rotation: Crop rotation helps control soil erosion by making the soil undisturbed by alternating crops. It plays a crucial role in improving soil structure and allowing organic matter to build up for the upcoming crops.

Organic Manures: Using organic manure like cow dung and green manure in agricultural fields improves the overall moisture of the soil. It also increases the infiltration and permeability in the soil.

Stubble Mulching: Keep the stubble or mulch on the soil to control the wind access to the soil.

Mechanical Measures

Contour Tillage: Tillage should be done at the right angle to the slopes. Through this, each furrow cuts off the flowing water, allowing it to soak into the soil.

Terracing: Terracing is practised all over India to control soil erosion. Cultivating sloping lands into flat surfaces reduces the amount of water flowing across the soil surface, thus preventing soil erosion.

Water Harvesting: Water harvesting is another important measure to control soil erosion. It collects and stores rainwater, which reduces the surface runoff.

What are the Government Initiatives to Reduce Soil Erosion?

National Mission for Sustainable Agriculture (NMSA): NMSA was launched by the Department of Agriculture and Farmer's Welfare in 2014-15. The scheme aims at agricultural productivity, especially in rainfed areas, focusing on integrated farming, water use efficiency, soil health management and synergizing resource conservation.

Soil Health Card Scheme: The Soil Health Card scheme was launched in 2015 with the initiative of improving farmers' soil quality and profitability and generating employment for rural youth. This card monitors the health of the soil and enables farmers to decide which crop to cultivate in their agricultural fields. This scheme has been merged with the Rashtriya Krishi Vikas Yojana (RKVY) cafeteria scheme as its one component under the name 'Soil Health & Fertility' from 2022-23.

Paramparagat Krishi Vikas Yojana (PKVY): As an extended component of the Soil Health Management (SHM) under the National Mission on Sustainable Agriculture (NMSA), the PKVY plays a crucial role in promoting and supporting organic farming. Its primary objective is to enhance soil health through the adoption of organic farming practices.