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Ecology is a very popular word today. But what does it mean? Ecology is a science which studies the relationship between all forms of life on our planet and the environment. This word came from Greek “oikos” which means home. The idea of home includes our whole planet, its population, Nature, animals, birds, fish, insets and all other living beings and even the atmosphere around our planet.
Since ancient times Nature has served Man giving everything he needs: air to breathe, food to eat, water to drink, wood for building and fuel for heating his home. For thousands of years people lived in harmony with the environment and it seemed to them that the resources of nature had no end or limit. With the industrial revolution our negative influence on Nature began to increase. Large cities with thousands of steaming, polluting plants and factories can be found nowadays all over the world. The by-products of their activity pollute the air we breathe the water we drink the fields where our crops are grown.
So, pollution is one of the most burning problems of nowadays. Now millions of chimneys, cars, buses, trucks all over the world exhaust fumes and harmful substances into the atmosphere. These poisoned substances pollute everything: air, land, water, birds and animals. Everything in large cities is covered with soot and dirt. All these affect harmfully. Every year the atmosphere is polluted by about 1000 tons of industrial dust and other harmful substances. Big cities suffer from smog. Cars with their engine have become the main source of pollution in industrial countries. Vast forests are being cut down for the need of industries in Europe and USA. The loss of the forests upsets the oxygen balance of the new wastelands. As the result some species of animals, birds, fish and plants have disappeared and keep disappearing.
Water pollution is very serious, too. Ugly rivers of dirty water polluted with factory waste, poisoned fish are all-round us. And polluted air and poisoned water lead to the end of the civilization. So, nowadays a lot of dead lands and lifeless areas have appeared.
What is the greenhouse effect, and is it affecting our climate? The greenhouse effect is essential for life on Earth. It is the result of heat absorption by certain gases in the atmosphere (called greenhouse gases because they trap heat) and re-radiation downward of a part of that heat. Water vapor is the most important greenhouse gas, followed by carbon dioxide and other trace gases. Without a natural greenhouse effect, the temperature of the Earth would be about zero degrees F (-18°C) instead of its present 57°F (14°C). However, the concern is with the question regarding whether human activities are leading to an enhancement of the greenhouse effect.
Environmental protection is of a universal concern. That is why serious measures to create a system of ecological security should be taken. Some progress has been already made in this direction. 159 countries - members of the UNO - have set up environmental protection agencies. Numerous conferences have been held by these agencies to discuss problems facing ecologically poor regions including the Aral Sea, the South Urals, Semipalatinsk and Chernobyl. An international environmental research center has been set up on Lake Baikal. The international organization Greenpeace is also doing much to preserve the environment. But these are only the initial steps and they must be carried onward to protect nature, to save life on the planet not only for the sake of the present but also for the future generations.