Soils of India and Soil Conservation

Soil Degradation

• Soil Degradation refers to the process by which the soil loses its quality thereby affecting its ability to support vegetation, particularly agricultural crops.
• There can be multiple reasons for deforestation both natural as well as Human Generated.
• In nature degradation of soil happens on its own but the rate is such that the natural process is able to replenish the degradation.
• The major problem arises due to the Human generated factors which has increased the rate of soil degradation much more than the capacity of nature to restore the damage.
• Soil degradation is a serious global environmental problem and may be exacerbated by climate change. It encompasses physical, chemical and biological deterioration.

Factors aggravating soil degradation

• • Extent, intensity, and duration of rainfall.
  • Wind speeds, particularly over drier regions.
  • Human activities such as deforestation, overgrazing by cattle, faulty agricultural practices, diversion of natural channels of drainage, and improper orientation of infrastructures such as roads, railways, bridges, and embankments.

 

Soil Conservation

• Soil conservation is the prevention of soil from erosion or reduced fertility caused by overuse, acidification, salinization or other chemical soil contamination.
• Soil erosion is the greatest single evil to Indian agriculture and animal husbandry.
• According to S.P. Chatterjee – “Soil erosion is the greatest single evil to Indian agriculture and Animal Husbandry.”
• Productive and healthy soil ensures the prosperous agriculture, industrial development, economic development and higher standard of living.
• According to S.I Kayastha – “With Soil Conservation people rises and with its destruction they fall.”

Various methods of Soil Conservation

Various methods used for Soil Conservation includes –

1. 1. 1. Afforestation
      2. Checking Overgrazing
      3. Construction of Dams
      4. Salinity Management
      5. Maintaining PH levels of soil
      6. Green Manures
      7. Windbreakers in Deserts
      8. Stream Bank Protection
      9. Reclamation of Ravine and Badlands
      10. Restriction on Shifting Cultivation
      11. Improving Agricultural Practices
          1. Crop Rotation
          2. Strip Cropping
          3. Contour Ploughing
          4. Terracing and Contour Bunding
          5. Using Early maturing Varieties
          6. Ploughing the Land in Right Direction
      12. Other methods

A. Afforestation for Soil Conservation

• • It includes the prevention of forest destruction along with growing new forests or increase area under forests.
  • A minimum area 20-25 % of forest land was considered healthy for soil and water conservation for the whole country.
  • This minimum area was raised to 33 % in the second five year plan – 20 % for the plains and 60 % for hilly and mountainous regions.
  • A dense amount of trees in a forest leads to a vast network of deep roots that offer a long term solution to soil erosion, another benefit is the windbreak that these trees can provide.

B. Checking Overgrazing 

• • Overgrazing leads to the serious problem of Soil erosion.
  • During the dry period, there is shortage of fodder and the grass is grazed to the ground and torn out to the roots by animals. This leads to loosening of top soil.
  • So overgrazing needs to be checked to prevent soil erosion.
  • By creating separate grazing grounds and producing larger quantities of fodder, Overgrazing can be easily checked.

C. Construction of Dams for Soil Conservation

• • Much of the soil erosion by river floods can be avoided by constructing dams across the rivers. This checks the speed of water and saves soil from erosion.
  • Dams also helps in providing the water all-round the year for various purposes including agriculture.
  • But indiscriminate dam construction can worsen the condition by creating floods and landslides like it happens in the Himalayan region.

D. Salinity Management

• • Salinity in soil is caused by irrigating with salty water. When water evaporates from the soil, it leaves behind its salt.
  • High levels of salt in the soil can often be caused by changes made to the water table by damming or by capillary action.
  • This can lead to damage of the soil and nutrient loss.
  • Using right techniques can prevent this or growing crops like Dhaincha can rejuvenate the soils and replace lost nutrients.
  • Application of gypsum and Cow dung is also quite helpful.

E. Maintaining Ph levels of soil

• • Contamination of soils due to acid rains and other pollutants can lead to loss of soil fertility which can in turn leads to low yield.
  • This can be checked by regularly examining the soil for its ph.

F. Green Manures

• • Green manures are a few different crops e.g. Dhaincha that can be grown, not for produce or food usage, but grown in order to fertilize the farm land on which it grows.
  • This method can improve the soil structure and suppresses the growth of weeds.
  • Moreover, it provides the much needed organic content or humus to the soil which increases its fertility.

G. Windbreaks

• • Dense rows of tall trees are used in patterns around the land to prevent wind erosion.
  • They are of much importance near coastal areas and near deserts so as to prevent the expansion of Badlands.

H. Stream Bank Protection

• • During floods, stream banks can often be eroded due to the force of water.
  • This can be prevented by constructing walls along the banks or plant useful trees. This will help in reclaiming the lands along the rivers

I. Reclamation of Ravine and Badlands

• • Reclamation of Ravines and Gullies is also necessary to overcome the problem of soil erosion.
  • Construction of Bunds across the gullies, plugging of gully mouths, levelling of Gullies, afforestation etc. are under implementation in Chambal ravines.

J. Restriction on Shifting Cultivation

• • Shifting agriculture also known as Slash and Burn agriculture, practiced in North eastern states of India, should be restricted. It leads to deforestation as well as soil erosion.
  • In place of shifting agriculture, sedentary farming and terrace farming should be promoted.
  • This can be done by making arrangements for their resettlement which involves the provision of residential accommodation, agricultural implements, seeds, manures, cattle and reclaimed land.

K. Control of Floods

• • Floods which generally occurs during rainy season are one of the main reason of soil erosion.
  • Efforts should be made for storage of this additional water or diverting it to ponds etc.
  • River link projects can do excellent work.

L. Mulching

• • The bare ground (top soil) between plants is covered with a protective layer of organic matter like grass clippings, straw, etc.

Benefits

• • Protects the soil from erosion.
  • It helps to retain soil moisture.
  • Reduces compaction from the impact of heavy rains.
  • Conserves moisture, reducing the need for frequent watering.
  • Maintains a more even soil temperature.
  • Prevents weed growth.
  • Organic mulches also improve the condition of the soil. As these mulches slowly decompose, they provide organic matter which helps keep the soil loose.

M. Improving Agricultural Practices for Soil Conservation

• • By changing our agricultural practices to a little extent, we can improve or help in soil conservation.
  • Adopting sustainable agricultural practices is the most important measure to conserve soil.
  • Some methods for soil conservation by improving agricultural practices are –

1. Crop Rotation

• • • • In many parts of India, a particular crop is sown in the same field year after year which leads to exhaustion of certain nutrients from the soil making it infertile.
      • Crop rotation is a practice in which a different crop is cultivated on a piece of land each year.
      • This helps to conserve soil fertility as different crops require different nutrients from the soil. Crop rotation will provide enough time to restore lost nutrients.
      • Legumes such as peas, beans, and many other plants, add nitrates to the soil by converting free nitrogen in the air into nitrogenous nodules on their roots. Thus if they are included in the crop rotation nitrogenous fertilizers is required in lower quantities.

2. Strip Cropping

• • • • Crops may be cultivated in alternate strips, parallel to one another. Some strips may be allowed to lie fallow while in others different crops may be sown.
      • Various crops are harvested at different intervals. This ensures that at no time of the year the entire area is left bare or exposed.
      • The tall growing crops act as wind breaks and the strips which are often parallel to the contours help in increasing water absorption by the soil by slowing down run off.

3. Contour Ploughing

• • • • Contour ploughing orients furrows following the contour lines of the farmed area.
      • In this, ploughing is done at right angles to the hill slope, the ridges and furrows break the flow of water down the hill.
      • This prevents excessive soil loss as gullies are less likely to develop and also reduce run-off so that plants receive more water.

4. Terrace farming

• • • • Terrace Farming is the practice of creating nearly level areas in a hillside area. The terraces form a series of steps, each at a higher level than the previous.
      • These are made on the steep slopes so that flat surfaces are available to grow crops. They can reduce surface run-off and soil erosion.
      • Retaining walls of terraces control the flow of water and help in reducing soil erosion.

5. Contour Bunding

• • • • Contour bunding involves the construction of banks along the contours.
      • Stones, grass, soil are used to build barriers along contours. Trenches are made in front of the barriers to collect water.
      • They intercept downslope flowing water and soil particles. These barriers slow down the water movement and reduce its erosive force.
      • Terracing and contour bunding which divide the hill slope into numerous small slopes, check the flow of water, promote absorption of water by soil and save soil from erosion.
      • A long term advantage of barriers is that soil tends to build up behind them, creating a terrace effect.

6. Use of Early Maturing Varieties

• • • • Early maturing varieties of crops take less time to mature and thus put lesser pressure on the soil. In this way it can help in reducing the soil erosion.

7. Ploughing the Land in Right Direction

• • • • Ploughing the land in a direction perpendicular to wind direction also reduces wind velocity and protects the top soil from erosion.

8. Rock dam

• • • • Rocks are piled up across a channel to slow down the flow of water. This prevents gullies and further soil loss.

9. Intercropping

• • • • Different crops are grown in alternate rows and are sown at different times to protect the soil from rain wash.
      • The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources that would otherwise not be utilized by a single crop.

N. Other Methods for Soil Conservation

• • Solving the problem of water logging by improving the surface and vertical drainage.
  • Increasing use of organic and compost manure.
  • Filling up gullies and forming terraces along the slopes.
  • Adopting the technique of sustainable agriculture.
  • Promotion of afforestation on degraded land.
  • Restricting felling of trees.
  • To educate people on Soil Conservation and its methods.

Achievements in Soil Conservation

• State Government and State Government has taken various steps to conserve soil.

A. First Five Year Plan

• • Central Government has set up soil and water conservation division under the Department of Agriculture and Cooperation which aims at providing overall perspective of problems such as water and wind erosion, degradation through waterlogging, salinity, ravines, shifting agriculture, and coastal sands.

B. Third Five Year Plan

• • Central Government introduced another program which aimed at preventing premature siltation of multi-purpose reservoirs.

C. Seventh Five Year Plan

• • Centrally sponsored scheme for reclamation of alkaline (usar) soils in states of Haryana Punjab and Uttar Pradesh was launched which is still continuing.
  • The scheme was extended to Gujarat, Madhya Pradesh and Rajasthan during Eighth Five Year Plan.
  • In ninth year plan it was extended to all other states where alkali soil problem exists as per scientific parameters.
  • Schemes aims at improving physical conditions and productivity status of alkali soils for restoring optimum crop production.

D. Ninth Five Year Plan

• • A program was launched for catchment management of River Valley Projects and Flood Prone Rivers. In this program 53 catchment are covered spread over 27 states.

• Besides these various Government Schemes have been launched from time to time.
• In 1987-88, Ravine Reclamation Program was launched by central Government which later on was transferred to State Governments. Under the Program, peripheral bunding to stop the expansion of ravines, afforestation, irrigation of shallow ravine and rehabilitation was initiated.
• Contour Bunding have been used effectively in Maharashtra, Gujarat, Tamil Nadu, Punjab etc. which resulted in increasing of the crop yield as well as helpful in recharging of water table.
• Scheme for controlling Shifting Agriculture was implemented in Arunachal Pradesh and Mizoram in 1986-87. In 1987-88, a larger scheme was launched to cover 9 states namely Arunachal Pradesh, Assam, Meghalaya, Manipur, Tripura, Nagaland, Mizoram, Odisha and Andhra Pradesh. The Scheme involves different activities such as land development, horticulture, cottage industries, fisheries, social and fuel-wood forestry and minimum housing program.
• All India Soil and Land Survey Organisation is using remote sensing technology to keep itself updated of the latest trends.

So, this was all about the Topic, Soils of India  in Indian Geography.

In the next post (Click here), We will start a new topic ‘Indian Agriculture’.