Environmental
Pollution
The presence of
unwanted changes which includes the matter
like gas, liquid, solid and energy
like heat, noise, radiation that occurs in the air, water and soil known as pollution or environmental pollution. The main reasons for this are
ü Population
explosion.
ü Rapid
and uncontrolled urbanization.
ü Modernizing
of agricultural methods.
The harmful
substances which cause changes in the environment by affecting the living
organisms known as pollutants.
·
Pollution is measured in PPM (Parts Per Million)
Air Pollution
The
presence of chemicals, particulates or biological materials that causes discomfort or death to living
organisms and environment known as air
pollution.
·
Composition
of Air : 78% nitrogen, 21% oxygen and 1% xenon, argon, helium, neon etc.,
Pollutants in Air
|
Pollutant
|
Sources
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Effects
|
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Carbon
monoxide: It is a gas that cannot be seen and smell
|
Vehicle’s smoke, burning fossil fuels.
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circulatory system (inhalation of gas
mixes with the haemoglobin and forms carboxyhaemoglobin), fatal development.
|
|
Sulphur
dioxide: It is a gas that cannot be seen but gives a smell of rotten egg.
|
Coal-fired power plants, petroleum
refineries.
|
Eye irritation, chest tightness,
respiration problem, loss o f chlorophyll (chlorosis) in plants, monuments – Tajmahal
(turns to yellow colour).
|
|
Carbon
dioxide: It is a gas that stays in the air for a long time and warm up
the temperature of the planet by trapping the sunlight which results as Green
House Effect
|
Industrial hazards, decayed plants
|
Rise of temperature, changes in forest
composition, damage to land.
|
|
Acid
rains: It is a combination of Nitrous oxide and Sulphur dioxide, when dissolves
in rain water it forms sulphuric acid and Nitric acid.
|
Nitrous oxide & Sulphur dioxide.
|
Water, trees, buildings, respiration
problem.
|
|
Aerosols:
It is a suspension of fine solid or liquid particles from a gas containing
chlorofluoro carbons.
|
Industrial hazards, biomass combustion.
|
Destroys ozone layer.
|
Water Pollution
It
is the contamination of water bodies like lakes,
rivers, oceans etc., which
occurs when pollutants are discharged directly or indirectly to the water
bodies. The main reasons for this are
ü
Industrial effluents.
ü
Sewages.
ü
Water contaminated with insecticides,
fungicides, chemicals.
Ø
Sources
of Water Pollution
·
Point
sources: It occurs when the harmful substances enter directly into the
water. Example: Pipes to rivers.
·
Non-point
sources: It occurs when there is a runoff of harmful substances into the
water. Example: Fertilizers to
streams.
Ø
Fluorosis
·
It is caused by excessive fluorine in the water, by taking such type of water results in
crippling and pains to the body.
·
Symptoms
include softening and bending of bones, dental problems (changes occur in the
enamel).
Ø
Eutrophication
The excessive richness of materials in the water by nutrients (animal
waste, fertilizers) from the land, causes dense group of life, decomposition of
plants (oxygen supply will be low) leading to death of animal life.
Ø
Biodegradation
A process in which the substances can be broken down into simpler compound
by micro organisms
Examples: excreta, sewage, pollen grains, etc.
Ø
Non
Biodegradation
A process in which the substances cannot be breakdown or taking an
inordinate amount of time to do so (because they cannot be dissolved by the
bacteria).
Examples: Common
plastics, DDT, metal wastes such as lead, mercury, arsenic, etc.
Thermal Pollution
The pollution of
water by excess heat than its original known as thermal pollution. It occurs when water is used as a coolant near
the industrial plants, then returns
to the aquatic environment at a high temperature.
Land Pollution
It is the degradation of the earth’s land surface
through misuse of the soil by poor agricultural practices, mineral
exploitation, industrial wastes, radioactive wastes etc. Control measures of Pollution
·
Water pollution can be prevented by collecting
human and cattle faeces in septic tanks and Gobar Gas Plants.
·
Thermal pollution can be controlled by fixing cooling
towers.
·
Water pollution can be controlled by treating
the effluents in effluent treatment plants.
·
Air pollution can be controlled by reducing the
use of vehicles.
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