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AIR CONTAMINATION CAUSED BY HUMAN ACTIVITY

1. AIR CONTAMINATION

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 C.[1]

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 uninhabited.

2. AIR CONTAMINATION IN RUSSIAN FEDERATION

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 35-30%»[5].

«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.

AIR CONTAMINATION IN RUSSIAN FEDERATION

Реферат опубликован: 3/01/2008