Рефераты Air contamination caused by human activity

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Air contamination caused by human activity
Insertion into atmosphere or the creation of the chemical agents and
substances caused by natural, and anthropogenous factors forms an air
contamination. The natural sources of contamination of an atmosphere are
volcanos, wood fires, dusty storms, a weathering etc. These factors do not
threaten with negative consequences to natural ecosystems, except some
catastrophic natural phenomena. For example, the eruption of a volcano
Cracatao in 1883, when into atmosphere 18 km cubes of ashes powder were
thrown out ; eruption of a volcano Catmay (Alaska) in the 1912 that had
thrown out 20 km cubes of friable products. The ashes of these eruptions
were spread over large part of the surface of the Earth and has caused the
reduction of solar radiation by 10-20 % that accordingly has caused in
northern hemisphere reduction of annual average temperature of air by 0.5
However per the last decades the anthropogenous factors of an air
contamination became to exceed by scales natural factors, acquiring global
character. They can render various effects on atmosphere: direct - on state
of the atmosphere (heating, change of humidity etc.); influence on chemical
properties of the atmosphere (change of structure, increase of
concentration of carbon dioxide, aerosols, freons etc.); influence on
properties of a spreading surface (change of size, albedo, system «ocean -
atmosphere» etc.)
To basic sources of contamination we can refer: the industrial
enterprises, transport, power system, agriculture etc. Among industries
especially toxic wastes are made by enterprises of colour metallurgy,
chemical, petrochemical, black metallurgy, wood-working, pulp&paper
industry etc.
«If you live in the advanced country, with probability 2:3 you breathe
by air that does not meet the standards»[2]. Is this air bad enough? It's
bad enough to cause 50 thousand anticipatory death annually. It's
potentially enough bad to destroy ecosystem and to make the Earth

The ecological problems of the Russian society have become aggravated
recently so, that without their consideration it is impossible to decide
political and economic tasks, to form a notion of prospects of social
development. «A Level of ecological safety, in opinion of the experts, is
lowest: 94 % of the interrogated experts have evaluated an ecological
situation in country as unsuccessful»[3].
The analysis of the statistical data of the amount of wastes of harmful
substances in atmosphere during 90-s' has shown that on the whole in
Russian Federation during this period there was a significant decrease of
wastes by 6525000 tons or 19 % [4].
So, «in 1992 in comparison with 1991 wastes of contaminating substances
in atmospheric air from stationary sources have decreased less than by 17
%. Althogh the level of production in almost all branches was decreased by
«Leaders» of wastes of harmful substances in an atmosphere during 3
years are Krasnoyarsk region, the Tyumen, Sverdlovsk, Chelyabinsk, Kemerovo
area and these areas only by the given parameter it is necessary to
attribute to a zone of the ecological catastrophe (see table). As you see
most contaminated regions are economic centers of Russian Federation and
unfortunately most populated.


| | |
|Region |Wastes into atmosphere |
| |Thousands tons |% |
|Russian Federation |31804,2 |100,0 |
|Including | | |
|Krasnoyarsk region |3182,7 |10,0 |
|Sverdlovsk area |2401,8 |7,5 |
|The Tyumen area |2369,8 |7,4 |
|The Chelyabinsk area |2060,5 |6,0 |
|The Kemerovo area |1208,9 |4,0 |
|The Vologda area |978,0 |3,0 |
|Irkutsk area |967,0 |3,0 |
|The Orenburg area |911,8 |3,0 |

Source: Demidenko L
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