BIO-GEO CHEMICAL CYCLE OR NUTRIENT CYCLE Bio - Living organism Geo - Rock, Soil, Air, Water Chemical - Material or Nutrients Cycle - Path All the types of material required by ecosystem in addition of energy, are available continuously to system through recycling. Thus there is a constant exchange of materials between the living organism and their abiotic environment through the recyling of materials. This phenomenon is called Bio-geo chemical cycle. Note: Environment factors,e.g soil , moisture, ph, temperature etc, regulate the release of nutrients into the atmosphere. Biochemical cycle The following types of cycle are found in an ecosystem. (i) Gaseous Cycle - C, H, N. O cycles. Reservoir is in the atmosphere (air) or in Hydrosphere(water). Sedimentary cycle - P. S, Ca cycles reservoirs are in earth's crust (lithosphere). Note : In these cycles, the bulk material remains in the inactive reservoir on earth crust like sediment of sea, or water
SOUND POLLUTION
Increase in the noise in the atmosphere is called noise pollution or sound pollution. Noise is a loud and unwanted or unpleasant sound. The common things which are responsible for noise pollution are - industries and mills,means of transportation, television stereo, loud speaker and jet plant etc.
Intensity :- The intensity of sound is measured in bel or decibel ( 1 bel = 10 decibel). Normally at 25 decibel,
the atmosphere may be peaceful. Above 80 decibel intensity of sound is called noise pollution.
Note : In India, the Air (Prevention and Control of Pollution) Act came into force in 1981, but was amended
in 1987 to include noise as an air pollutant.
A brief exposure to extremely high sound level, 150 dB or more generated by take off of a jet plane or rocket,may damage ear drums thus permanently impairing hearing ability. Even chronic exposure to a relatively lowernoise level of cities may permanently damage hearing abilities of humans. Noise also causes sleeplessness,increased heart beating, altered breathing pattern, thus considerably stressing humans.
Note : Reduction of noise in our industries can be affected by use of sound absorbent material or by muffling noise.
Green muflur scheme. Tree such as neem and ashoka absorb sound to a great extent, along road side.
Solid wastes refer to evgerything that goes out in trash. Municipal solid wastes are wastes from homes, offices,
stores, schools, hospitals, etc., that are collected and disposed by the municipality. The municipal solid wastes generally comprise paper, food wastes, plastics, glass, metals, ruber, leather, textile, etc. Burning reduces the volume of the wastes, although it is generally not burnt to completion and open dumps often serve as the breeding ground for rats and flies. Sanitary landfills were adopted as the substitute for open-burning dumps. In a sanitary
landfill, wastes are dumped in a depression or trench after compaction, and covered wth dirt everyday.
Landfills are also not really much of a solution since the amount of garbage generation specially in the metros has increased so much that these sites are getting filled too. Also there is danger of seepage of chemicals, etc.,from these landfills polluting the underground water resources.
RADIOACTIVE POLLUTION
The various sources of radioactive materials as follows.
Natural sources - Cosmic rays, radiation from the earth such as Radium - 224, Uranium 235, Uranium238, Thorium 232, Radon 222, Potassium - 40 and Carbon 14.
Man made Radiation - The radiations are released in the atmosphere during mining and purification of Thorium and Plutonium, and in producing nuclear weapons etc. Nuclear reactor and nuclear fuel causes pollution by radioactive radiation. The nuclear fuel and coolants
are the sources of radioactive radiation. Radioactive waste is also most important radio active pollutants
because these wastes are not dumped at particular or right place.
Other sources - Some of the radioactive elements (isotops) are used in experimental laboratories for
scientific researches which causes radio active pollution. X-rays are also proved to have harmful effects.
The first is accidental leakage of radiation occurred in the Three Mile Island and Chernobyl.
It has been recommended that storage of nuclear waste, after sufficient per treatment, should be done in suitably shielded containers buried within the rocks, about 500 m deep below the earth's surface.
SPECIAL POINT
Air pollution : According to central pollution control board (CPCB), particulate size 2.5 micrometers or less in diameter are responsible for causing the greatest harm to human health. These fine particulates can be inhaled deep into the lungs and can cause breathing and respiratory symptoms, irritation, inflammations and damage due to the lung and premature deaths.
Catalytic converters : Automobiles are a major cause for atmospheric pollution in the metro cities. Proper maintenance of automobiles along with use of lead free petrol or diesel can reduce the pollutants they emit.Catalytic converters, having expensive metals namely platinum - palladium and rhodium as the catalysts, are fitted into automobiles for reducing emission of poisonons gases. As the exhaust passes the catalytic converter,
unburnt hydrocarbons are converted into CO² and water, and CO and nitric oxide are changed into CO² and nitrogen gas respectively.
Motor vehicles equipped with catalytic converter should use unleaded petrol because lead in the petrol inactivates
the catalyst.
CNG (compressed natural gas) :-
In the 1990s, Delhi ranked fourth among the 41 most polluted cities of the world.
All the buses of Delhi were converted to run on CNG by the end of 2002.
CNG is the better than diesel because CNG burn most efficiently as compare to diesel or petrol in the automobiles and very little of it is left unbrunt. CNG is cheaper than petrol or diesel.
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3. MIC (Methyl Isocyanate) was released in Bhopal gas tragedy on 3rd December 1984. Which is used in the production of "Savin" insecticide in Union Carbide.
4. Tetraethyl lead and tetramethyl lead are formed by combustion of petroleum. They are known to hamper haemoglobin formation.
The disease produced by use of lead polluted water is called as plumbism.
Lead causes nervousness anaemia in human beings. It also damages kidney.
Lead concentration in blood is considered alarming if it is 10 ug/100 ml.
5. Common dust disease is known as Pneumoconiosis.
* Disease due to cotton dust in textile workers is - Lung fibrosis or Byssinosis
* Disease due to coal dust - Anthracosis
.* Disease due to asbestos dust - Asbestosis
* In stone grinders disease due to sillica dust - Sillicosis
* In Iron mill disease due to iron dust - Siderosis
* Cadmium causes anaemia, hypertension, damage to liver and kidneys. In Japan it caused bone softening or skeleton deformitcis called Itai-Itai disease or Ouch-Ouch
6. Stone leprosy is caused due to acid rain because due to acid rain outer surface of metals, marbles, and stone destroyed.
7. Blue Baby disease :- This disease is caused by the high amount of nitrate in water. It is also known as methaemoglobinaemia or cyanosis.
8. Hypertension and Uremia - Caused by Copper
9. Arsenic :- It causes black-foot disease and poisoning in fodder plants which are eaten by live stock and causes their death.
10. Fluorides - The higher concentration of fluorides causes chlorosis or necrosis in tips and margin of leaf (leal lamina). The compounds of fluorine reach in the animals through the fodder and causes abnormal calcification of teeth, this is called Fluorosis.
Note: The experts hold that the maximum level of fluoride which the human body can tolerate is 1.5( parts per million ppm). When ingested in excess over a long period of time causes "Fluorosis".
11. ELNino effect - It is the process in which water of Pacific ocean get warm, in this process warm water curren flows to equator & peru in between 5 to 8 year at christmas time. Effect of ELNino is flood, drought and monsoon damage in India. On the other hand when cold water comes in effect in pacific ocean it is called La-Nina effect.
12. Major pollutant in Jet Plane emission is CFC.
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