Civilization advertises many advantages but also products pollution and damages the environment in which we live.Pollution affects air, water, land, forests, people, animals and plants.Technology has an important role in reducing pollution(development, recycling). Air pollution is from smoke, dust, smog(from coal fires and car exhausts).Smoke contains sulphur dioxide (SO2), nitrogen oxide (NO) and carbon dioxide which are produced by coal power stations and industrial plants burning fossil fuels.It may causes climate changes.These substances mix with water vapour in the atmosphere and form sulphuric acid and nitric acid.Sunlights turn these acids into poisonous oxidants which fall in the form of acid rains on trees and slowly kill them.Trees are vitally important for us because they absorb carbon dioxide and change him in oxygen.But in Asia and South America(Amazon) great rain forests are extract for firewood and materials.With more carbon dioxide in the air, the temperature will rise, the icecaps at the North and South Poles melt and it may cause flooding in many coastal cities.Another problem is greenhouse effect.It means that the Earth is warmed up and icecaps melt by sunlightes because of atmospheric emissions such as carbon dioxide(produced by burning fossile fuels), nitrogen oxides(from car exhausts), CFCs(chlorofluorocarbons from aerosol and refrigerators čili freony), methane(bioproduct of agriculture), water vapour and ozone.Ozone is also pollutant in lower atmosphere above all at summer.It is produced by the reaction of sunlight and gas from car exhausts.Ozon can causes asthma, corrosion and stunted growth of plants.On the other hand, ozone forms ozone layer in the upper atmosphere which protects us from ultraviolet rays which cause cancer of skin.CFCs damage this layer and thus causes ozone hole over Antarctica.The problem of air pollution can be solved by using alternative sources of energy(solar, water, wind, geothermal and tidal) or burning smokeless fuels, reducing road traffic(switch road traffic to railroad, keep the speed limit, using catalytic converters, using unleaded petrol, switch from coal to gas power, use low sulphur coal, installation of flue gas desulphurisation plants at power stations)
Water pollution is from industrial processes, pesticides and chemicals in agriculture, waste disposal sites, substandart sewage plants and ships.Main pollutants are nitrate and heavy metals such as mercury, cadmium, lead, copper.Nitrate becomes from organic and anorganic fertilizer.The problem of water pollution can be solved by reducing the amount of chemicals in the water.We must minimazed or stopped discharges from industrial processes and the number of sewage treatment plants must increased.To prevent nitrate pollution farmers can change their farming practices, for example by growing "green cover"crops in the autumn to take up residual nitrogen.International agreements control oil discharges. Soil contamination is from industrial waste.It can be avoided by re-using, recycling or energy recovery.Land can be also contaminated by radioactive substances.More than 80% comes from natural sources.Spent nuclear fuel has been stored for at least 50 years to allow much of the heat and radioactivity to decay.
Noise is problem for many people all above in big cities.It can cause stress, lack of oncentration, defective hearing or sleepeness.The problem of noise is solved by regulating oise from car engines and regulating airport services. Human must also protect animals and plants because the balance of species is affected by human activities.Some animals are protected(bats, badgers) others are bred in captivity for the best chance of survival.National Parks and nature reserves provide protection and also opportunity for recreation.For recreation, there is also green belts(parks) around big cities in Britain(London, Edinburgh, Glasgow, Manchester).
*catalytic converters-turn dangerous gases(oxides of nitrogen-NOx, hydrocarbons and carbon monoxyde) into CO2 and water vapour
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