Soil pollution is defined as, “contamination of soil by human and natural activities which may cause harmful effect on living organisms”.

Causes of Soil Pollution:

1. Industrial wastes

Disposal of Industrial wastes is the major problem for soil pollution. This has probably been the biggest contributor in the last century, especially from mining and manufacturing, as the by-products are often contaminated, and not disposed of properly.

2. Urban wastes

Urban wastes comprise of both commercial and domestic wastes consisting of garbage and rubbish materials like plastics, glasses, metallic cans, fibres, paper, rubbers etc. Urban wastes, can be dangerous. This happens because they are not easily degraded.

3. Agricultural practices 

Modern agricultural practices pollute the soil to a large extent. With the advancing agro-technology, huge quantities of fertilizers, pesticides, herbicides and weedicides are added to increase the crop yield. They are full of chemicals that are not produced in nature and cannot be broken down by it. As a result, they seep into the ground after they mix with water and slowly reduce the fertility of the soil.

4. Radioactive pollutants

Radioactive substances resulting from explosions of nuclear testing laboratories and industries giving rise to nuclear dust radioactive wastes, penetrate the soil and accumulate giving rise to land/soil pollution.

5.Accidental Oil Spills

Oil leaks can happen during the storage and transport of chemicals. This can be seen at most of the fuel stations. The chemicals present in the fuel deteriorates the quality of soil and make them unsuitable for cultivation.

6. Acid Rain

when there are pollutants in the air, and it starts to rain, they mix and fall back to the ground, causing acid rain. This pollution can then dissolve important nutrients, changing the structure of the soil.

7. Biological agents

Soil gets a large amount of human, animal and bird excreta which constitute a major source of land pollution by biological agents.

Effects of Soil Pollution on Human Beings

Crops and plants that are grown on polluted soil absorb much of the pollution and then pass these on to us. This could explain the sudden surge in small and terminal illnesses.Long term exposure to such soil can affect the genetic make-up of the body, causing chronic health problems that cannot be cured easily. In fact, it can cause food poisoning over a long period of time.

Effects on Plants and Animals

Since soil pollution is often accompanied by a decrease in the availability of nutrients, plant life ceases to thrive in such soils. Soils contaminated with inorganic aluminum can prove toxic to plants. Also, this type of pollution often increases the salinity of the soil, making it inhospitable for the growth of plant life. Effects on the Ecosystem

Since the volatile contaminants in the soil can be carried away into the atmosphere by winds or can seep into underground water reserves, soil pollution can be a direct contributor to air and water pollution. It can also contribute towards acid rain (by releasing huge quantities of ammonia into the atmosphere). Crop yield is greatly affected by this form of pollution. In China, over 12 million tons of grain (worth approximately 2.6 billion USD) is found to be unfit for human consumption due to contamination with heavy metals (as per studies conducted by the China Dialogue).

Control measures of soil pollution:

1. Soil erosion can be controlled by a variety of forestry and farm practices. Ex: Planting trees on barren slopes. Contour cultivation and strip cropping may be practiced instead of shifting cultivation.

2. Proper dumping of unwanted materials: Excess wastes by man and animals pose a disposal problem. Open dumping is the most commonly practiced technique. Nowadays, controlled tipping is followed for solid waste disposal. The surface so obtained is used for housing or sports field.

3. Production of natural fertilizers: Bio-pesticides should be used in place of toxic chemical pesticides. Organic fertilizers should be used in place of synthesized chemical fertilizers. Ex: Organic wastes in animal dung may be used to prepare compost manure instead of throwing them wastefully and polluting the soil.

4. Proper hygienic condition: People should be trained regarding sanitary habits. Ex: Lavatories should be equipped with quick and effective disposal methods.

5. Public awareness: Informal and formal public awareness programs should be imparted to educate people on health hazards by environmental education.

6. Recycling and Reuse of wastes: To minimize soil pollution, the wastes such as paper, plastics, metals, glasses, organics, petroleum products and industrial effluents etc should be recycled and reused.

7. Ban on Toxic chemicals: Ban should be imposed on chemicals and pesticides like DDT, BHC, etc which are fatal to plants and animals.