the largest recognisable terrestrial unit which conains living things is called a biome
any change in the environment which contributes to its deterioation with substances that make it harmful is called pollution
| bio degradable |
non biodegradable |
| can be broken down into simple non poisonous substances by the action of micro organisms |
cannot be broken down into simple non poisonous susbtances by the action of micro organisms |
| can be recycled naturally and by humans. their products do not pollute the environment |
they cannot be recycled naturrally by humans. |
| do not disturb the ecological balance |
they disturb the ecological balance |
| ex- paper, banana peels |
DDT, pesticides. |
air pollution
the air which contains traces of undesirable gases, liquids or solid components.
sources
- exhaust from automobiles adds carbon monoxide, nitric oxide, etc
- volcanic erruptions throw out particulate matter which pollute the air
- burning of fuel for domestic purposes
- mining of coal and other minerals.
- a combination of smoke and dust make smog which pollutes the air
effects
- temperature inversion- the pollutants prevent the hot air from rising causing the temperature to increase
- acid rain- it is the precipitation that contains large amounts of sulphuric and nitric acid [decreases soil fertility, destroys aquatic life and destroys monuments]
- smog- the ozone present in smog deteriorates rubber articles, throat infections and asthma
- global warming- green house gases trap heat and does not let it escape therefore acting as a greenhouse. [heatwaves of unusually hot weather, rising of sea levels, melting of glaciers]
- ozone depletion- [uv rays can easily reach human, development of plants is effected.]
- health problems- we are more susceptable to infections and diseases with harmful particulate matter in the air.
water pollution
sources
- sewage and other domestic wastes [eutrophication]
- pesticides and agricultural runoff
- oil spills
- industrial waste [mercury]
- nuclear wastes
effects
- the presenc of acids & alkalis in water destroys micro-organisms
- adversely effects aquatic life
- toxic materials may enter the food chain causing sever health hazards
- decreases soil fertility.
- what is thermal pollution?
- what is biomagnification?
- what are some other health problems regarding water pollution?
soil and land pollution
land pollution is the contamination of land by solid waste.
any substance that reduces the productivity of soil is known as a soil pollution
- soil fertility is reduced by acid rain
- & soil erosion!
radioactive fallouts
harmful effects
- chemical pesticides are used to kill crop pests
- domestic animals eat contaminated food and die
sources
- cosmic radiation
- c-14 and k-40
- poor ventilation
harmful effects
- radioactive pollution destroys living tissues and blood cells.
- lead to mutations in genes and are carcenogenic
chernobyl accident
- what is noise pollution?
- what is bio medical waste?
abatement of pollution
- use of leaded petrol should be banned, CNG should be used
- sewage should be fully treated- physically and chemically before it is released into the river.
- marine pollution should be controlled by collecting the oil off the water surface and use chemicals to disperse the oil