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11. Environmental Protection Civilization has brought people many advantages but its products also pollute and damage the environment in which we live. Some countries have been implementing policies to protect the environment against pollution from industry and other sources for more than a century, while in the Czech Republic we are only at the beginning. Pollution affects air, water land, forests, people, animals and plants. Technology has an important role to play in reducing pollution and developing new means for reducing harmful emissions. It can be used to protect the environment in several ways, including basic changes, which result in less waste or pollution, and developing ways to recycle materials. Waste materials, which were previously dumped, can be converted into useful products. “End-of-pipe" systems can be installed to clean up emissions. And cleaner or less harmful alternative products may be manufactured. Air pollution is the biggest problem in large cities and in areas with concentrated industrial production. Emissions range from smoke, dust, and smells to car and lorry exhausts. What happens? First factories send gases and chemicals into the air, there they mix and are carried for hundred miles by the wind. Trees are vitally important for our life because they are the lungs of our planet. They absorb carbon dioxide from the air and give out oxygen in return. In some parts of the world, such as Asia and South America, trees are not threatened by pollution, but by people. The great rain forests are being destroyed for firewood and building materials. Since the Amazon rain forest covers an area as large as the whole of Europe and contains one third of the world’s trees, scientists believe that it provides 50 per cent of the worlds annual production of oxygen. If we lose tropical forests, it will become more difficult, perhaps even impossible, to breathe. With more carbon dioxide in the air, the temperature will rise; the ice caps at the North and South Poles will melt, and the sea level will rise which wi1l result in the flooding of many coastal cities. Several gases have been identified as contributing to the "greenhouse effect", which can also cause climate change. Without this "greenhouse effect" there could be no life on earth because the earth is warmed up naturally by the atmosphere, which traps solar radiation. But manmade atmospheric emissions, such as carbon dioxide (produced by burning fossil fuels), nitrogen oxides (from car exhausts), CFCs (chlorofluorocarbons from aerosol and refrigerators), methane (a by-product of agriculture from rice, cattle and sheep) and water vapour prevent the heat from escaping. The result is a rise in the Earth's temperature, the melting of arctic ice and the flooding of areas situated near sea level. Smoke from coal fires, which causes smog, also represents a considerable problem in large cities and threatens life. How can the problems of air pollution be solved? First of all, people should try to use alternative sources of energy, such as solar, water, wind, geothermal and perhaps tidal energies, or at least to burn smokeless fuels. There are more ways to reduce air pollution caused by road traffic. First it is possible to switch freight from road to railways and to support public transportation. Another way is to encourage tree planting, because trees absorb carbon dioxide. Then all new petrol-driven cars will have to be fitted with three-way catalytic converters in their exhaust systems which turn dangerous gases into CO: nitrogen and water vapour. The first commercial auto catalysts in the world where made in Britain in 1974. Lead emissions can fall if we reduce lead content in petrol and encourage the use of unleaded petrol. Water pollution results from harmful industrial processes and households, from various chemicals used in agriculture, from waste disposal sites, plants and ships. Land and soil can be contaminated by domestic rubbish, industrial waste and radioactive substances. More than 80% of radiation to which the public is exposed comes from natural resources. Only about thousands of the total comes from the disposal or the discharge of radioactive waste. Noise represents a considerable problem for many young people. It results in stress, lack of concentration, defective hearing and sleepless. Environmental protection should also include animal and plant protection because of balance of species, so some animals and plants are protected and kept in Natural Parks and Reserves.