Реферат: Nature Protection
Nature Protection Computers project that between now and the year of 2030 we are going to have increase of the average temperature between 1,5—4,5 Degrees C. Sea levels would rise by several metres, flooding coastal areas and ruining vast tracts of farmland. Huge areas would be infertile and become uninhabitable.
Water contamination could lead to shortages of safe drinking water. It looks like the end of civilization on the Earth. For hundreds of thousands of years the human race has thriven in Earth's environment. But now, at the end of the 20th century, we are at a crucial turning point. We have upset nature's sensitive equilibrium releasing harmful substances into the air, polluting rivers and oceans with industrial waste and tearing up the countryside to accommodate our rubbish. These are the consequences of the development of civilization. We are to stop it by joint efforts of all the people of the world.
The range of environmental problems is wide. But the matters of people's great concern nowadays are atmosphere and climate changes, depletion of the ozone layer, freshwater resources, oceans and coastal areas, deforestation and desertification, biological diversity, biotechnology, health and chemical safety. United Nations Environment Programme (UNEP) concentrates its activities on these issues.
Acid Rains One of the most alarming forms of air pollution is acid rain. It results from the release into the atmosphere of sulphur and nitrogen oxides that react with water droplets and return to earth in the form of acid rain, mist or snow. Acid rain iskilling forests (Nearly every species of tree is affected) It has acidified lakes and streams and they can't support fish, wildlife, plants or insects.
Depletion of the Ozone Layer The protective layer of the Earth, the ozone layer, which protects the Earth from the sun's destructive UV (ultraviolet) rays, is being damaged by CFCs (chlorofluorocarbons). They are released by the daily use of industrial and household products: refrigerators, air conditioners, foam insulation, cleaning chemicals, food packaging. In the ozone layer they attack the ozone molecules making a «hole».
This «hole» allows more UV rays to penetrate to the Earth. It increases the risk of skin cancer, weakens the immune system of people. Besides, UV rays influence the oceans, the growth of plankton, an essential part of the marine-life food chain in the negative way, reduce economically important-crops (rice, cotton, soy beans). The life cycle is going to be undermined by the ozone. Destruction of the Tropical Forest It's generally agreed that the destruction of the tropical forest has a major impact on the world climate.
The tropical rain forest is a natural recycler, provider and protector for our planet. It recycles carbon, nitrogen and oxygen, helps determine temperature, rainfall and other climatic conditions and supports the most diverse ecosystem in the world. Deforestation could cause one forth of all species on earth to vanish in the next 25 years. These forests in Amazonia, South-East Asia and West and Central Africa are being destroyed at an alarming rate of 42 million acres per year. Measures to Be Taken We have only a few years to attempt to turn things around.
We must review our wasteful, careless ways, we must consume less, recycle more, conserve wildlife and nature, act according to the dictum «think locally, think globally, act locally». To my mind, we are obliged to remove factories and plants from cities, use modern technologies, redesign and modify purifying systems for cleaning and trapping harmful substances, protect and increase the greenery and broaden ecological education. These are the main practical measures, which must he taken in order to improve the ecological situation. Some progress has been already made in this direction. 159 countries-members of the UNO have set up environmental protection agencies. They hold conferences discussing ecological problems, set up environmental research centres and take practical urgent measures to avoid ecological catastrophe. There are numerous public organisations such as Greenpeace that are doing much to preserve environment. The 5th of June is proclaimed the World Environmental Day by the UNO and is celebrated every year.