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Write an essay on water pollution of soil

Essay on Soil Pollution: Definition, Causes and Effects Article shared by: Read this essay to learn about Soil Pollution. After reading this essay you will learn about: Definition of Soil Pollution 2.

Causes of Soil Pollution 3. Definition of Soil Pollution: The organic portion, which is derived from the decayed remains of plants and animals, is concentrated in the dark uppermost topsoil. The inorganic portion made up of rock fragments, was formed over thousands of years by physical and chemical weathering of bedrock.

Productive soils are necessary for agriculture to supply the world with sufficient food. Soil pollution is defined as persistent of toxic compounds, chemicals, salts, radioactive materials, or disease causing agents, which have adverse effects on plant growth and animal health. Soil becomes polluted by: Seepage from a landfill.

  • Pyrolysis of carbonaceous wastes like firewood, coconut, palm waste, corn combs, cashew shell, rice husk paddy straw and saw dust, yields charcoal along with products like tar, methyl alcohol, acetic acid, acetone and a fuel gas;
  • Below mentioned are the major effects of soil pollution and how it affects all living things;
  • Environmental and aesthetic considerations must be taken into consideration before selecting the dumping sites;
  • Sewage effluents, agricultural wastes like animal and crop residues etc;
  • Percolation of contaminated water into the soil.

Discharge of industrial waste into the soil. Percolation of contaminated water into the soil. Rupture of underground storage tanks. Excess application of pesticides, herbicides or fertilizer. Chemicals like petroleum hydrocarbons, heavy metals, pesticides and solvents. Causes of Soil Pollution: A soil pollutant is any factor which deteriorates the quality, texture and mineral content of the soil or which disturbs the biological balance of the organisms in the soil.

Pollution in soil has adverse effect on plant growth. Mainly soil pollution is caused by the presence of man-made chemicals application of pesticides, percolation of contaminated surface water to subsurface strata, oil and fuel dumping, leaching of wastes from landfills or direct discharge of industrial wastes to the soil.

The most common chemicals involved are petroleum hydrocarbons, solvents, pesticides, lead and other heavy metals. Occurrence of this phenomenon is correlated with the degree of industrialization and intensities of chemical usage.

The main causes of soil pollution are described below in details: Haphazard Use of Fertilizer: Soil nutrients are vital for plant growth and development. Plants obtain carbon, hydrogen and oxygen from air and water.

Write an essay on water pollution of soil

All other necessary nutrients like nitrogen, phosphorus, potassium, calcium, magnesium, sulfur and more must be obtained from the soil. Farmers generally use fertilizers to correct soil deficiencies.

Fertilizers contaminate the soil with impurities, which come from the raw materials used for their manufacture. For instance, As, Pb and Cd present in traces in rock phosphate mineral get transferred to super phosphate fertilizer. Since the metals are not degradable, their accumulation in the soil above their toxic levels due to excessive use of phosphate fertilizers becomes an indestructible poison for crops. Fertilizers are very valuable, as they replace the soil nutrients used up by plants.

The three primary soil nutrients often in short supply are potassium, phosphorous and nitrogen NPK compounds. These are commonly referred to as macronutrients. Certain other elements like boron, zinc and manganese are necessary in extremely small amounts and are known as micronutrients.

When crops are harvested, a large amount of macronutrients and a small amount of micronutrients are removed with the crops. If the same crop is grown again, depleted levels of the nutrients can result in decreased yields.

These necessary nutrients can be returned to the soil through the application of fertilizers. The over use of NPK fertilizers reduce quantity of vegetables and crops grown on soil over the years. It also reduces the protein content of wheat, maize, grams, etc. The carbohydrate quality of such crops also gets degraded. Excess potassium content in soil decreases vitamin C and carotene content in vegetables and fruits.

  • The reaction of these elements in soil is certainly affected by the pH, organic matter content, and, the redox status of the soil;
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  • The incorporation or injection of sludge protects the natural ecosystems by preventing environmental problems caused by run-off and volatilization;
  • Deforestation is slowly destroying the most dynamic flora and fauna areas.

The vegetables and fruits grown on over- fertilized soil are more prone to attacks by insects and disease. The use of chemical fertilizers has increased significantly over the last few decades and is expected to rise even higher. Indiscriminate use of Pesticides, Insecticides and Herbicides: In addition to fertilizers, a large amount of pesticides chemicals used to kill or control populations of unwanted fungi, animals or plants often called pests are also used to ensure a good yield.

Pesticides can be subdivided into several categories, based on the kinds of organisms they are used to control. Insecticides are used to control insect populations, while fungicides are used to control unwanted fungal growth.

Mice and rats are killed by rodenticides, while plant pests are controlled by herbicides. Insects soon became resistant to DDT and as the chemical did not decompose readily, it persisted in the environment. Since it was soluble in fat rather than water, it biomagnified up the food chain and disrupted calcium metabolism in birds, causing eggshells to be thin and fragile. As a result, large birds of prey such as the brown pelican, ospreys, falcons and eagles became endangered. DDT has been now banned in most western countries.

Ironically many of them including USA still produce DDT for export to other developing nations whose needs outweigh the problems caused by it. The most important pesticides are DDT, BHC, chlorinated hydrocarbons, organophosphates, aldrin, malathion, dieldrin, furodan, etc.

The remnants of such pesticides may get adsorbed by the soil particles, which then contaminate root crops grown in that soil.

Essay on water pollution of soil

An infamous herbicide used as a defoliant in the Vietnam War called Agent Orange dioxinwas eventually banned. It had caused cancer, skin conditions and infertility in soldiers. Pesticides not only bring toxic effect on human and animals but also decrease the fertility of the soil. Some of the pesticides are quite stable and their bio- degradation may take weeks and even months. For example, DDT, one of the first synthetic organic insecticides to be used, was thought to be the perfect insecticide.

During the first ten years of its use 1942-1952DDT is estimated to have saved about five million lives primarily because of its use to control disease-carrying mosquitoes. However, after a period of use, many mosquitoes and insects became tolerant to DDT, thus making it lose its effectiveness.

In temperate regions, DDT has a half-life the amount of time required for half of the chemical to decompose of 10-15 years.

Essay on Soil Pollution: Definition, Causes and Effects

This means that if 100 kg of DDT were to be sprayed over an area, 50 kg would still be present in the area 10-15 years later. The half-life of DDT varies according to the soil type, temperature, kind of soil organisms present, and other factors. In tropical parts of the world, the half-life may be as short as 6 months.

Persistent pesticides become attached to small soil particles which are easily moved by wind and water to different parts thus affecting soils elsewhere. Persistent pesticides may also accumulate in the bodies of animals, and over a period of time increase in concentration if the animal is unable to flush them out of its system, thus leading to the phenomenon called bioaccumulation.

When an affected animals is eaten by another carnivore, these pesticides are further concentrated in the body of the carnivore. This process, especially in the case of insecticides like DDT, has been proved to be disastrous. Dumping of Solid Wastes: In general, solid waste includes garbage, domestic refuse and discarded solid materials such as those from commercial, industrial and agricultural operations. They contain a large amounts of paper, cardboards, plastics, glass, old construction material, packaging material and toxic or otherwise hazardous substances.

Land gets dumping of industrial wastes, municipal wastes, medicals or hospital wastes. Industrial solid wastes and sludge are the major sources of soil pollution by toxic organic and inorganic chemical compounds and heavy metals.

The fall-out from industrial emissions, for example the fly ash emitted by thermal power plants, can pollute surrounding lands. We must keep in mind that the particulates of write an essay on water pollution of soil industrial emissions from the tall chimney always come back to the earth surface sooner or later. Radioactive tests from nuclear testing laboratories and nuclear power write an essay on water pollution of soil and the radioactive fall-out from the nuclear explosions also contaminate the soil.

Radioactive materials thrive in the soil for long periods because they usually have a long half-life. Stroncium-90, for example, has a half-life of 28 years, and the half-life of Caesium-137 is 30 years. Municipal wastes mainly include domestic and kitchen wastes, market wastes, hospital wastes, livestock and poultry wastes, slaughterhouse wastes, waste metals, glass and ceramic wastes, etc.

Hospital wastes contain organic materials, chemicals, metal needles, plastic and glass bottles, vials, etc. Dumping of domestic sewage and hospital organic wastes contaminate the environment with a variety of pathogens that can seriously affect human health. The portion of solid waste that is hazardous such as oils, battery metals, heavy metals from smelting industries and organic solvents are the ones we have to pay particular attention to.

These can in the long run, get deposited to the soils of the surrounding area and pollute them by altering their chemical and biological properties. Toxic chemicals leached into the soil underneath homes, causing an unusually large number of birth defects, cancers and respiratory, nervous and kidney diseases. Soil erosion occurs when the weathered soil particles are dislodged and carried away by wind or water.

Deforestation, agricultural development, temperature extremes, precipitation including acid rain, and human activities contribute to this erosion. Humans speed up this process by construction, mining, cutting of timber, over cropping and overgrazing.

It results in floods and cause soil erosion. Forests and grasslands are an excellent binding material that keeps the soil intact and healthy. They support many habitats and ecosystems, which provide innumerable feeding pathways or food chains to all species. Their loss would threaten food chains and the survival of many species.

During the past few years quite a lot of vast green land has been converted into deserts. The precious rain forest habitats of South America, tropical Asia and Africa are coming under pressure of population growth and development. Soil erosion occurs when the worn out particles are dislodged and passed away by wind or water.