2014-15

1. .

2. Pollution.
• Any undesirable change in physical, chemical
or biological property of environment is called
pollution.
• The factors that cause pollution are called
pollutants.
• Type of pollution.
1. Air pollution.
2. Water pollution.
3. Soil pollution.
4. Radiation pollution etc.

3. Air pollution
• Any undesirable
change in physical,
chemical or
biological property
of air is called air
pollution.
• The imp air
pollutants are
Oxides of sulphur,
Oxides of nitrogen,
Oxides of carbon,
Smoke, Smog and
ozone.

4. Effects of air pollution.
• Oxides of sulphur and
nitrogen causes
chlorosis and defoliation
of leaves in plants.

5. • In human beings
Oxides of sulphur and
nitrogen causes eye
irritation, nasal
irritation, chronic
cough, bronchitis etc.
• Oxides of sulphur and
nitrogen reacts with
rain water and causes
acid rain.

6. • Oxides of carbon results in green house effects

7. • The photochemical
smog destroys plant
vegetation.
• The ozone formed by
photochemical reaction
of oxides of nitrogen and
hydrocarbons at lower
level of atmosphere is
called photochemical
smog.

8. Control of air pollution:
• Electrostatic Precipitator:
• It removes 99% particulate
matter present in the
exhaust from thermal plant.
• It has electrode wires and a
stage of collecting plates.
• The electrodes releases
electrons. These electrons
get attached to the dust and
give them a net negative
charge.
• The collecting plates attract
the charged particles.

9. • Scrubber:
• It removes gases like SO2
industrial exhaust.
• Catalytic Convertor:
• Used in automobiles for
reducing emission of harmful
gases.
• Vehicles fitted with catalytic
converter should use unleaded
petrol as leaded petrol
inactivates the catalyst.
• Auto Fuel Policy:
• The Government of India laid
out a road map to cut down the
vehicular air policy in many
cities of India

10. Water pollution:
• Undesirable change in
physical, chemical or
biological property of water
is called water pollution.
• The imp water pollutants
are sewage waste. Industrial
waste. Chemical fertilizer
and pesticides.

11. Effect of water pollution on biodiversity:
• The sewage waste directly released to water
source stimulates the increase of pathogenic
microbes. It causes water born disease.
• The nutrition enrichment in water results
eutrophication and algal bloom. It increases the
BOD (biological oxygen demand).
• The pesticides enters the water resources leads to
bio-magnification.
• Industrial waste having heave metals and
chemicals release to water destroys the aquatic
organisms.
• The mercury that enters the human beings through
food chain causes Minamata disease.

12. • Eutrophication: The
process of increase in
algal production in
water due to
nutrition enrichment
is called
eutrophication.

13. • Bio-magnification: Accumulation of non
degradable chemicals, heavy metals in human
beings through food chain is called bio-
magnification.

14. • BOD (Biological oxygen demand):
• The amount of oxygen required for microbial
breakdown of biodegradable organic matter is called
BOD.
• BOD is higher in polluted water and lesser in drinking
water.
• Algla bloom:
• Excessive growth of planktonic algae on water body
surface.
• It causes fish mortality and pollute water.

15. • Radioactive wastes
• The waste produced from the nuclear fission of heavy atoms
such as uranium, thorium etc for the production of power is
radioactive waste.
• This waste is highly toxic and causes mutations and cancer.
• The nuclear waste should be stored after heavy treatment
and packed in special containers.
• It should be buried deep under the ground for minimum of 60
– 80 years for the waste to stabilize.
• Even then there is a high chance of nuclear contamination of
the surrounding areas & the ground water.
• Failure of nuclear power plants can have disastrous
consequences. The use of nuclear fuels should be avoided if
possible.

16. • Greenhouse effect and global
warming:
• Global warming refers to the
heating up of the Earth due to
greenhouse effect.
• Greenhouse effect is caused
when gases such as CO2, CH4
etc increase in the atmosphere.
• This leads to the heating up of
the earth as these are good
absorbers of heat.
• These gases prevent the excess
heat from leaving the Earth’s
atmosphere thus resulting in
greenhouse effect.

17. • Effects:
• It effects Arctic polar ice cap to
melt at the rate of 9% per
decade. The rise is the sea level
causes flood in certain
countries like Bangladesh,
Maldives etc.
• It causes food & water shortage.
Destruction of underwater cities
(coral reefs) & meadows result
in extinction.
• only in the colder climatic
regions global warming brings
comfort but in various other
places its effect is negative.

18. • Control measures of global warming:
1. Reforestation replaces maximum carbon dioxide by
oxygen.
2. Preventing Deforestation.
3. Reduction of fossil fuel burning can minimize
global warming.
4. Improving the efficiency of engines & turbines can
drastically reduce pollution.
5. Planting hundreds of trees across cities & in
homes.
6. Using natural resources like wind energy, solar
energy and wave energy may help to overcome
global warming.

19. • Depletion of ozone layer
Ozone is formed in the stratosphere by the effect of UV rays on
O2. The thickness of ozone is measured in Dobson units.
• Cause of ozone depletion:
• Ozone degradation has increased due to chlorofluorocarbon (CFC).
• CFC,s reacts with UV radiation to release chlorine atoms.
• Chlorine atoms are catalyst that degrades ozone to oxygen.
• The CFCs released in the lower part of the atmosphere move
upwards towards the south pole, hence depleting the ozone layer
over Antarctica.
• Harmful effects:
• UV damages the DNA results in mutation.
• It causes skin aging and skin cancer.
• Control measure:
• Montreal protocol was signed in 1987 to crub the emission of
ozone depleting substance like CFC.

20. • Freons:
• Chloro-Fluoro-Carbons are called freons.
• Ecosan:
• Ecosan is ecological sanitation. This approach is
useful in converting the solid human excreta into
manure.
• E-waste:
• It is the electronic waste which includes irreparable
components of electronic gadgets.

21. • .