Soil Pollution-Definition [Sources, Causes, Effect, Control, Prevention] of Soil Pollution

By the end of this article, you should be able to describe What is Soil Pollution, Definition, Sources, Causes, Effect, Control, Prevention of Soil Pollution. Let’s start discussing one by one.

What is Soil Pollution- Definition

Soil pollution is defined as the decrease in soil fertility because of the addition of some foreign elements. The soil is the most important component of the earth’s crust. The soil is polluted like air and water, but it remains restricted to the fields affected, unlike the air and water pollution.

Sources of Soil Pollution – (Causes of Soil Pollution)

Industrial Wastes

Industrial complexes discard millions of tons of solid wastes every year. The major sources of industrial pollutants are from pulp and paper mills, oil refineries, smelters, various chemical, power and heating plants. Almost all the industrial furnaces generate ‘fly ash’ which is added to the soil. 

Urban, Commercial and Domestic Wastes

Most of the waste is generated in the urban areas which include domestic, commercial and industrial waste. It is often dumped in public places, such as streets, parks, picnic areas, bus stops, near shops and in the open areas outside the city. These wastes include odd scraps, old newspapers, discarded papers, wooden furniture, lawn trimmings, glass, cans, old or broken appliances, tyres, plastics, etc. The accumulation of waste pollutes the soil. Several bacteria and virus germinate on the waste that enters the soil. Toxic acids are also produced from the heap of waste that leach down in the soil.

Agricultural chemicals and fertilizers

Modern agriculture demands the use of a variety of chemicals in pursuit of high productivity. The fertilizers are used to increase the yield of crops. Other much-used chemicals include the herbicides, fungicides and pesticides.

Biomedical wastes

Waste from the hospital is called biomedical waste. It includes needles, syringes soiled dressings, expired drugs, cotton, anatomical parts, etc. These are often infected and is capable of spreading diseases. The untreated waste can mix with soil and pollute it.

Biodegradable wastes

The biodegradable wastes break down and decompose in the soil. Micro-organisms like bacteria and fungi decompose the waste goods into simple compounds. These simple compounds are used as nutrients by other living organisms. The biodegradable wastes include peels of fruits and vegetables, leaves, grass, wood, paper, clothes, wool, etc.

Non-biodegradable wastes

These wastes include those materials which do not break down or decompose in the soil. The important non-biodegradable waste is made up of plastic goods, polythene bags, synthetic clothes, metals, chemicals, glass, cans, radioactive waste, styrofoam, etc.

Indirect result of air pollution

The acid rains are the result of air pollution. Acid rains in turn cause soil pollution. Acid rains, pesticides and other biocides are serious soil pollutants. They kill the essential soil microorganisms and induce toxicity in the soil for plant growth.

Effects of Soil Pollution

  1. Surface mining and strip mining remove top-soil and even subsoil. Sometimes, uncontrolled mine fires permanently destroy the productivity of the specific area.
  2. Industrial waste in most cases is very toxic and can pollute the soil. Presence of heavy metals in industrial waste is harmful to any soil which can be taken up by plants. Soil contaminated by heavy metals from agricultural and industrial waste will produce unhealthy food. Heavy metals enter the food chain and are consumed by human beings.
  3. Acid Rain kills the essential soil microorganisms and induces toxicity in the soil for plant growth.
  4. The Biomedical wastes are infected and are capable of spreading diseases.They play a huge role in polluting soil and spreading disease.

Prevention of Soil Pollution – (Control of Soil Pollution)

Prevention of soil pollution mainly involves

  • Judicious use of fertilizers, insecticides, pesticides, herbicides, fungicides, etc.
  • An efficient system of disposal of domestic wastes.
  • Restoring forests and grassland covers that check soil erosion, flood and waterlogging.
  • Crop-rotation and mixed cropping also help to improve the fertility of the soil.
  • Recycling and recovery of wastes.

Examples of Recycling Wastes

All the solid wastes should be pretreated and recycled. Minimum quantities of such wastes should be discharged. Some important cases of recycling of wastes are given below: Agricultural wastes (paddy husk, Corn cobs, remains of Crushed Sugarcane, fibrous Coat of coconuts, tobacco waste, waste paper) are converted into paper and board. Recycling of paper is costly but worthwhile in view of conservation of resources. It is estimated.that recovery of one ton of paper can save 17 trees. Jute waste is changed into hardboard. Seeds of neem, mahua, sal and other trees can yield fat and oil cake. Cattle-dung used in gobar gas plants provides cooking gas and enriched dung manure. Domestic wastes (fruit and vegetable peels, fallen leaves) can be disposed of in one’s own house by Composting. This practice not only reduces environmental pollution but also provides humus to replenish depleted soil resources. Clean water resulting from treatment of sewage and industrial Wastes can be reused.  Recovery of metals from scrap is economical. The use of biofertilizers and manures can decrease the need for chemical fertilizers. This can reduce Soil pollution and save money also.