Speech on Land Pollution: it’s Sources, Causes, Effects and Control Measures!
Land pollution may be defined as the presence of one or more contaminants in soil in such quantity and for such duration which is or tends be injurious to human health or welfare, animal or plant life, or property.
Sources of land pollution:
The rapid growth of industries and agricultural unit has resulted in the production of large amount of waste including:
(a) Municipal Waste
(b) Commercial Waste
(c) Agricultural Waste
(d) Industrial Waste
Causes of Land Pollution:
1. Land pollution by industrial waste:
Industrial discharge mainly from pulp and paper mills, chemical industries, oil refineries, sugar factories, tanneries, textiles, steel, fertilizers, pesticides industries , coal and mining industries, metal processing industries etc. cause major percentage of land pollution.
2. Land pollution by urban waste:
Urban waste is also called as refuse. It consists of commercial waste as well as domestic waste. This refuse contains garbage, rubbish materials like plastics, glasses, metallic cans, fibres, paper, fuel residue, containers and other discarded manufactured products. All this mainly contain non-biodegradable materials.
3. Radioactive Pollutants:
Radioactive substances coming from explosions of nuclear devices, atmospheric fallout from nuclear dust and radioactive waste penetrates the soil and accumulate there creating land pollution.
4. Agricultural Practises:
With advanced agro-technology, huge quantity of fertilizers, pesticides, herbicides, weedicides and soil containing agents are employed to increase the crop yield. Apart from this farm Waste, manure, slurry, dead bodies, soil erosion containing mostly inorganic chemicals are reported to cause soil erosion.
5. Chemical and metallic pollutants:
A number of industries including textile, pesticides, paints, dyes, soap and synthetic detergents, drugs, cement, petroleum, paper and pulp, electroplating and metal industries pour this hazardous chemical in soil and water creating disastrous effect on living organism.
6. Biological Agents:
Soil gets large quantity of human, animals and birds excreta which constitute the major source of land pollution by biological agents. The pathogenic organisms that pollute the soil may be classified into three categories:
(a) Pathogenic organisms like bacteria, fungi, algae etc.
(b) Pathogenic organisms excreted by man.
(c) Pathogenic organism excreted by animals.
Effects of Land Pollution:
Following are the effects of various pollutants:
1. Effect of Industrial Pollutants:
(a) Industrial effluent when discharged through sewage system will poison the biological purification mechanism of sewage treatment causing several soil and water borne diseases.
(b) Some trade waste contains pathogenic bacteria e.g., Anthrax bacilli is present in tannery waste.
2. Effect of Urban waste:
(a) Urban waste spread several chronic diseases posing a serious threat to human health.
(b) Solid waste cause offensive odour and cause clogging of ground water filters.
3. Effect of radioactive pollutants:
(a) Radioactive element like radium, Uranium etc. can remain active in soil for thousands of years.
(b) When food containing radioactive nuclides is taken by man, some of them concentrate in specific body organs where they cause a number of undesirable diseases of digestive tract.
4. Effect of modern agro-technology:
(a) Pesticides not only pose a potential hazard to man, animal, fishes and livestock but they severely affect the desired yield of crop and soil.
(b) Pesticides retained in soil concentrate in crops, vegetables and cereals and fruits which contaminate them to such as extent that they are not usable.
(c) Poly chlorinated biphenyls (PCBs) accumulate in the soil and plants which ultimately enter into human bodies. It’s concentration above 0.5g develop darkened skin, damage eye etc.
(d) Pesticides like DDT etc. are known to seep gradually through the soil into ground water and thus contaminate public drinking water supplies.
(e) Herbicides and pesticides are very potent pollutants of the soil and affect soil texture and function of the ecosystem.
(f) People in contact with pesticides, such as farmers, farm workers are much more prone to be poisoned by them which damage liver, kidney causing malnutrition, blood abnormalities etc.
5. Effects of Biological Agents:
(a) Pathogenic soil bacteria are chronic disease carriers which are transmitted from man to soil causing cholera, typhoid etc.
(b) The eggs of parasitic worms get incubated in the soil, these eggs and larvae are highly infective.
6. Effects of Sediments:
(a) Suspended particle is usually eroded top soil which is most fertile portion of soil.
(b) Sediments adversely affect the physical and chemical composition of water. It carries numerous ions (e.g., Na+, K+, NO3-, Cl- etc.) from the agricultural fields contaminated with pesticides.
(c) Suspended sediments like loads of clay and slit in the river water damages turbine which are used to generate hydroelectricity.
Control Measures for Soil Pollution:
Following are some practices by which soil pollution can be prevented to some extent:
1. Production of Natural Fertilizers. Organic waste contained in animal’s dung can be used for preparing compost manure and biogas rather than throwing them wastefully polluting the soil.
2. Ban on toxic chemicals. Ban should be imposed on chemicals, biocides and pesticides which are fatal to plants and animals.
3. Plantation and recycling of trees. Extensive plantation is extremely essential to prevent soil erosion.
4. Launching extensive afforestation and community forestry programmes.
5. Conservation of soil to prevent the loss of precious top soil from erosion and to maintain it in a fertile state for agricultural purposes.
6. Effective treatment of domestic sewage by suitable biological and chemical methods and adopting modern technique of sludge disposal.
7. Municipal waste has to be properly collected by segregation treated and disposed scientifically. Recycling of glass, paper, and plastics should be done carefully.
8. Imparting informal and formal public awareness programmes to educate people at large regarding health hazards and undesirable effects due to environmental pollution.