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Soil Pollution And Its Sources

Soil pollution is defined as, " the contamination of soil by human and natural activities which may cause harmful effects on living beings".



Types, Effects and Sources (Causes) Of Soil Pollution :

Soil pollution mainly results from the following sources 

1, Industrial wastes

2. Urban Wastes.

3. Agricultural Wastes.

4. Radioactive pollutants.

5. Biological agents.


I) Industrial Wastes : 

Disposal of  industrial wastes is the major problem for soil pollution. 

Sources :

The industrial pollutants are mainly discharged from the various origins such as pulp and paper mills., chemical industries, oil refineries, sugar factories, tanneries, textiles, steel, distilleries, fertilizers, pesticides, coal, and mineral mining industries, drugs, glass, cement, petroleum and engineering industries etc.,




Effect :

These pollutants affect and alter the chemical and biological properties of soil. 

As a result, hazardous chemicals can enter into human food chain from the soil and water and disturb the biochemical process. and finally lead to serious effects on living organisms.

II) Urban Wastes : 

Urban Wastes comprises both commercial and domestic wastes consisting of dried sludge of sewage. All the urban solid wastes are commonly referred to as refuse.



Constituents of  Urban refuse:

The refuse contains garbage and rubbish materials like plastics, glasses, metallic cans, fibers, paper, rubbers, street sweepings, fuel residues, leaves, containers, abandoned vehicles and other discarded manufactured products. Urban domestic wastes through disposed of separately from the Industrial wastes, can still be dangerous. This is so because they cannot be easily degraded.

III) Agricultural Wastes :

Modern Agricultural practices pollute the soil to a large extent. Today with the advancing agrotechnology, huge quantities of fertilizers, pesticides, herbicides, weedicides, are added to increase the crop yield. Apart from these farm wastes, manure, slurry, debris, soil erosion containing mostly inorganic chemicals are reported to cause soil pollution.




IV) Radioactive Pollutants :

Radioactive substances resulting from explosions of  nuclear dust and radioactive wastes ( produces by nuclear testing laboratories and industries ) penetrate the soil and accumulate there by creating land pollution.




Examples : 

Radio nuclides of radium, thorium, uranium, isotopes of potassium (K-40) and carbon (C-14) are very common in soil, rock, water and air. 

V) Biological Agents :

Soil gets large quantities of human, animal and bird's excreta which constitute the major source of land pollution by biological agents. 




Example - Heavy application of manures and digested sludges could cause serious damage to plants within a few years. Because the sludges are containing more live viruses and viable intestinal worms. 


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