maturitní otázky, seminárky a referáty
Angličtina - Environment
Autor: Kateřina Labaničová
Environment is the space surrounding places people live in. That means the whole nature of course, towns, our houses and flats and other people, too. When we say "environment" we usually think about destroying it and this is what a part of this theme is going to be about.
Destroying the environment is a result of mankind´s activity. The air pollution is caused by the industry, rivers and soils may be polluted by factories that release their waste waters into river streams.
Acid rains are caused by the air pollution. Gases in the air, such as dinitric oxide (N2O) and sulfuric dioxide (SO2), mix with water steam in the atmosphere and create nitric acid and sulfuric acid which rains down to Earth and pollutes water, soil and green plants, which has an effect on health of the organisms on the Earth.
Greenhouse effect is caused by carbonic dioxide (CO2) that is accumulated in the atmosphere and creates a continuous layer which allows sunrays to penetrate through the atmosphere towards the Earth but doesn´t allow them to go out. That means that the heat carried by sunrays stays in the atmosphere and the average temperature on Earth rises up. This influents the glaciers which melt, the sea level rises, and that causes floods.
Ozone hole is caused by dangerous gases containing chlorine and fluorine, used in sprays of all kinds. In the past, people believed they had discovered a chemical material without any by-effects, but later they realized how these gases cauterize the ozonosphere. Ozone is a three-atomized oxygen which protects the Earth and life on it against dangerous radioactive gamma sunrays. One molecule of chlorine can destroy 1000 molecules of ozone. The ozone layer in the atmosphere is becoming thinner and thinner. The situation is extremely bad above the southern hemisphere, esp. above Antarctic, Australia and New Zealand.
Cutting trees - no matter if rain forests or trees in general is one of today´s biggest problems. We mustn´t forget that all the green plants, not only trees, produce oxygen we breathe. The greatest percentage of this oxygen is produced by the rain forests in tropical zone (average temperature here is high above 10 °C all year round, which is the temperature needed for plants to make photosynthesis, and that is why e. g. trees in northern countries (Canada, Finland, Russia) don´t produce so much oxygen, although these countries have a great part of their area covered with forests. Although we know all of this many of us don´t care and still cut thousands of trees every day just to build a highway across Brazil. Rain forests are important not only for being lungs of the Earth but also because of providing home for thousands of animal and plant species, many of them still unknown. We also must not forget that 40% of medicaments ingredients come from tropical forests, esp. from Amazon.
Cutting trees is a problem in the poorest parts of the world. People in Sahel Africa burn all the trees they find because they need them to prepare food. Result of this is that deserts (Sahara) are getting larger. Great number of forests used to grow on the lower slopes of Himalayas. These trees kept the soil on its place. But people cut them down. Soil was left unprotected and when the monsoon came, the soil was flushed down to the valley and great floods of mud afflicted such states as India, Bangladesh and Bhutan.
Natural disasters. To me, natural disasters seem to be the way the Earth revenges all the bad things we have done to her.
Volcano activity and earthquake. Volcanoes are made when one lithospheric table gets under another one and under great pressure volcanic ranges arise, usually guided with earthquake. Hot magma rises deep from the heart of the Earth and gets out from crater as lava connected with volcanic gases and ash. Volcanoes can spout liquid lava or magmatic stones and ash. The most famous parts of the world connected with volcano activity are Italy, Japan and Hawaii. Earthquake at the bottom of the see can cause dangerous waves called Tsunami. These waves can be 10-15 meters high and can run more than 100kph.
Winds. Strong winds called tornadoes, hurricanes etc., can occur all around the world but somewhere are more often (Florida, Philippines,…). These whirlwinds carry tons of water during their way across the ocean and move by speed 250-500 kph.When hitting the coast, they destroy everything what stands in their way.