Page 139 - Genius Kidz Prudence Learning Sc-8

corrosive in nature. Sources of water pollution : There are two
Prevention of air pollution :
Air pollution is one of the alarming challenges
faced by the entire world. Some of the
methods that can be used for prevention of air
pollution are enlisted below :
! Switch over to the use of unleaded fuels.
! Make use of catalytic converters that can
convert harmful pollutants into harmless
compounds.
! Use of sulphur should be minimized.
! Wastes from the industries must be treated
prior to their discharge into the atmosphere.
! Encourage afforestation and plantation.
! Car pooling and use of public transport
should be chosen over private vehicles.
! Bicycles must be prefered over fuel based
vehicles.
! Laws must be made strict over checking of
air pollution.
! CNG based vehicles must be favoured over
petrol based vehicles.
! CFC’s substitutes as hydro chloro fluoro
carbons (HCF) must be encouraged.
WATER POLLUTION
Definition : Any undesirable change in the
physical, chemical or biological properties of
water is called water pollution. Substances
that cause water pollution are called as water
pollutants.
Water pollution
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types of sources of water pollution on the basis
of their location :
(a) Point sources : These are those that are
located at a fixed point and are discharging
the pollutants from there.
(b) Diffused sources : These are those that are
scattered over areas thus causing pollution
from scattered sites.
Types of Water pollution : Types of water
pollution are the following :
(a) Surface water pollution : Pollution of
surface water bodies.
(b) Underground water pollution : Pollution of
underground water like that within soil or
under rocks. Pollution of underground
water bodies is caused by pesticides mainly.
(c) Microbiological water pollution : Pollution
of water caused by microbes is called
microbiological water pollution. It is caused
by algae, protozoa, viruses, bacteria, etc.
(d) Industrial water pollution : Water pollution
caused by the run off from different types
of industries. Examples of industrial
pollutants include solvents, pesticides,
petroleum, chemicals, fertilizers, etc.
Types of water pullution