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Save The Earth

]Pollution is an unwanted change in the physical, chemical, or biological characteristic of the environment, caused by human activities.

These ones lead to a several environmental disasters, like acid rains, global warming and ozone depletion. These problems involve, above all, the atmosphere, soil, rivers and seas.

Pollutans can be biodegradable and non-biodegradable. The former, example sewage, may be dissolved through natural processes. The latter, example heavy metals, do not break down by microorganisms methabolism and, therefore, they accumulate in the environment.

Noxius gases, which are released by factories, could fall down in the ground with the rain. These precipitations have an acid pH value less than about 5.0 and bring about adwise effects on the fauna and flora, causing the death of plants.

Another noxius smog is produced by the reaction between nitrogen oxide an hydrocarbons in the presence of ultraviolet light. The reaction leads also to the production of harmful ozone which composes the closer layer from us. The ozone layer that guards us against ultraviolet radiation is further than that one harmful. The chlorofluorocarbon emissions in the atmosphere is damaging this precius gas as they react whit it. This reaction is allowed by ultraviolet radiation and it's creating an ozone hole over both the poles.

Motor veichle exhaust emissions produce high quantities of carbon dioxide. This gas can absorb infrared radiation coming from the energy carried by light and ultraviolet radiation of Sun, which warm the Earth up. Infrared radiation are emitted by carbon dioxide as a heat form: this phenomenon is called Greenhouse Effect.

Greenhouse effect brings about global warming, which is responsable of the icelands and glaciers melting. The disappearance of polar ice caps causes an increasement of sea level.