modern ecological problemsOne of the most acute environmental problems of the present time is air pollution. At an early stage of development of the biosphere, the air is polluted only volcanoes and forest fires. However, further
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modern ecological problems One of the most acute environmental
problems of the present time is air pollution. At
an early stage of development of the biosphere, the air is polluted only volcanoes and forest fires. However, further rapid development of industry and transport has led to a sharp deterioration of the atmosphere. Currently in the atmosphere as a result of human activities do carbon dioxide and other hydrocarbons. Sources of pollution are burning of fossil fuels burning of forests emissions of the industrial enterprises and exhaust gases of cars.
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modern ecological problems The growth in atmospheric concentrations of
carbon dioxide and methane creates a greenhouse effect. These
gases let the sun's light, but partially delay the reflected thermal radiation from the Earth's surface. Over the last 100 years the relative concentration of carbon dioxide in the atmosphere has increased by 20% and methane by 100%, which led to an increase in average temperature on the planet by 0.5 °C. If in the coming years the concentration of these gases will increase at the same rate, by 2050 the Earth will be warmer by 2-5 °C. This warming can lead to melting of glaciers and rising Global sea level of almost 1.5 m, causing flooding of many populated coastal areas.
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modern ecological problems substances contained in exhaust gases of
vehicles under the influence of sunlight enter into complex
chemical reactions forming toxic compounds. Together with water drops, they form a toxic fog smog which is harmful effect on the human body, in plants.
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modern ecological problems Fresh water is less than 1%
of the total world supply of water and mankind
is wasting and polluting this precious wealth. Population growth, improved living conditions, industrial development and irrigated agriculture have led to the fact that water waste has become a global problem of humanity
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modern ecological problems The whole river is taken for
irrigation and the needs of the cities, and along
the beds of these rivers and at the mouth of the die of the natural community. Analysis of the water of the rivers of Central Asia has led to that ceased to exist the Aral sea. The salt from his dried bottom is carried by the wind, causing salinization of the soil for miles around.
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modern ecological problems Equally dangerous phenomenon is the contamination
of water bodies. With fields and pastures fall into
the water of organic matter. Sewage drains that dump water into the sea without any treatment pose a threat to human health. Because of the accidents of tankers and pipelines to the ocean annually pours out a huge amount of oil.
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modern ecological problems Discharges from industrial facilities. Superficial drains
from landfills is often contaminated with heavy metals and
synthetic organic materials. Salts of heavy metals cause human poisoning with severe consequences.
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modern ecological problems Dwelling houses and domestic enterprises. The
composition of pollutants in this source category is dominated
by household waste, food waste, construction waste etc is collected and landfilled. The burning of garbage in the city dump is accompanied by release of toxic substances, which are deposited on the surface of the soil and difficult to wash off by rain.