Презентація на тему «Pollution» (варіант 3)
Types of pollution
Imbalance in the quality of air so as to cause adverse affects on the living organisms existing on earth.
Causes of air pollution
Pollen grains of flowers
Emission from vehicles
Contamination of water by addition of undesirable organic, inorganic or biological substances to water sources
Natural sources: soil erosion, leaching of minerals from of rocks and decay matter.
Destroys ecosystem and effects human health
Sources of water pollution
Community waste waters
Under ground water pollution
Undesirable change in the physical, chemical or biological property which adversely affects its productivity
Caused by dumping of wastes, agrochemicals and as indirect result of air pollution
Sources of Soil Pollution
Physical pollution that affects air, water and soil. Caused by ionizing radiations of harmful nature emitted from disintegrating atomic nuclei.
The natural sources include cosmic rays that reaches the earth surface and radiations from radium 224, uranium 235 thorium 232 etc
Man made sources
Reactors and Nuclear fuel
Waste waters containing these wastes
X-rays used in medical practices
Ultra violet rays present in solar radiations
Radioactive substances in food chain cause retarded growth and bone cancer.
Increases infant mortality rate
Unwanted high pitch sound that pollutes the environment.
Maximum tolerable intensity of sound is 85 decibels
The main sources are automobiles, aero planes, loudspeakers, industries and other electro-mechanical devices.
Effects of noise pollution
Damage to ear drum and impairment to hearing.
Damages heart, liver and brain
Emotional disturbances and behavioral changes
Leads to anxiety and stress
The term thermal pollution has been used to indicate the detrimental effects of heated effluents discharged by various power plants.
Causes of thermal pollution
Nuclear power plants
Coal fired power plants