II. Make up a list of actions one should undertake in case such an accident occurs. 


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II. Make up a list of actions one should undertake in case such an accident occurs.



 

Text 4

Read the text and make resume of it:

The time "cures", but there is no safe spot

While people create radioactive elements, they do not have any methods to reduce their radioactivity. Only time is capable of doing so. For example, he period of semi-disintegration of carbon - 14 is 5900 years. The period of semi-disintegration of strontium - 90 is 28 years. But some parts of radiation remain forever. And it is not possible to do anything with this, except to bury the radioactive substances in а safe place. But where is it possible to find this safe place for the huge amounts of radioactive wastes, produced as а result of the production activities of the people?

No place on Earth can be considered safe enough for such kind of activity. Some time ago people thought that it was possible to place these wastes into the deepest places of the oceans, suggesting that life is not possible in those areas. But then this idea was refuted by deep underwater research done by Soviet scientists. Everywhere, where life is present radioactive substances join the biological cycle. А few hours after these materials were placed under water it is possible to trace them in living organisms. Sea-weeds and many sea animals accumulate radioactive substances in- concentrations, which are thousands of times higher than concentrations of the same substances in the surrounding water. And since some of the organisms serve as food for other ones, radioactive substances gradually come back to humans.

Some scientific and research centers study the "maximum limits of concentration" (MLС) and "maximum admissible levels" (MAL) of various radioactive elements. MLС implies certain amounts of the given radioactive substance, which may be accumulated inside human bodies without causing any harm to the health of the person. But it is well-known that any accumulation eventually causes damage. In Western countries attempts were made to determine, which dozes of radiation are tolerable and even the "maximum admissible levels" were developed, but they did not by any means solve the problem.

The international agreement on radioactive wastes burial has not yet been reached. The 1959 Monaco Conference of the International Nuclear Energy Agency lead only to disagreements among countries. "Highly radioactive" wastes are continuously thrown into the ocean, "moderately" and "low" radioactive wastes are dumped into rivers or just on the ground.

 

UNIT VI.

OVERPOPULATION

WARM UP.

How do you think what is better: demography explosion or demography crisis. Explain your point of view.

 

1. Study the vocabulary:

1. increasingly (зд.) значительно

2. controversial спорный

3. assumption предположение

4. to collapse рушиться

5. ingenuity изобретательность

6. to cope with справляться

7. scarce скудный

8. to aggravate усугублять, обострять

9. estuary широкое устье реки

10. to deplete истощать, исчерпывать

11. habitat среда обитания

2. Read and translate the text:

Population Growth

A major question is the effect of the growing population on the environment. The search for answers to this question has become increasingly(1) complex and controversial(2). In general, ecologists and biologists tend(3) to be pessimistic about the damage growing populations cause to the environment, based on their assumption(4) that ecosystems have a limited “carrying capacity”(5), or ability to support life. Eventually, they say, the environment will no longer be able to renew itself and will collapse (6). Economists, on the other hand, are often optimistics; they trust the free market and human ingenuity(7) to develop new technology for coping with(8) ever-larger numbers and scarce resources. “But no science so far has been able to actually quantify the role of population on the environment,” says Robert Engelman, director of the Population and Environment Program at Population Action International in Washington, DC. “at this point, there’s no direct way to prove that, say, 80 million more people in a region had a particular impact on the water or air quality. However, it is clear that population is often the critical variable that can cause the degradation and even collapse of natural systems.”

As population grows, so will the pressure new generations exert on natural resources. The list of environmental problems aggravated(9) by growing populations includes deforestation and desertification, loss of top soil, poisoning of drinking water and pollution of oceans, shrinking wetlands, shortage of fuels such as firewood, exhaustion of oil reserves and of various mineral resources, siltation in rivers and estuaries(10), dropping water tables, erosion of the ozone layer, loss of species and wilderness areas, global warming, rising sea levels, nuclear waste, air pollution, and acid rain.

Any population increase often means putting more land under cultivation and raising the production per acre(11), steps that can require more capital, fertilizers, pesticides, and water irrigation. In the United States Almost all arable land is now under production, leading to soil erosion. Water consumption naturally rises with population growth, and the country’s huge groundwater aquifers are disappearing. Parts of Texas and Arizona have already been pumped dry and can no longer be farmed. In addition, rapidly growing populations in Mexico, the Philippines, Indonesia, Brazil have caused environmentally fragile lands to be overfarmed and depleted. The loss of natural habitats to more and more cropland reduces the biological diversity(12) of plants and animals. Water tables are quickly dropping in the developing world, especially in the Middle East and Africa. The numbers of people there have risen beyond the water’s ability to renew itself. And in Zambia, for example, population size has generally exceeded the forest’s ability to regenerate. So the forest has stopped, and is now moving back.

In addition, While the world population was doubling between the 1950s and 1980, its commercial energy consumption increased threefold. As a result of the higher demand, energy suppliers are mining more coal and building more dams and hydroelectric and nuclear power plants. The increases activity has led to higher levels of polluting emissions and waste. Levels of carbon dioxide and methane in the atmosphere are also tied(13) to a region’s population size. With more than 20 million people, Mexico City has the largest population of any city in the world, and the worst air pollution. Demographers predict its population will grow to more than 30 million people. In the United States alone, ever-increasing car driving and industrial activities now pump an estimated 23 million tons of sulfur dioxide into the atmosphere. The acid rain this chemical helps create then damages aquatic and forest life, often thousands of miles away from the source. However, some experts argue that environmental problems are not a sole result of population size.

 

COMPREHENSION

1. Join these split sentences and translate them:

1.The question concerning the effect of the growing population on the environment   2. Ecologists and biologists tend to be pessimistic   3. The list of environmental problems aggravated by growing population   4. Water consumption naturally rises   5. The numbers of people have risen     a) about the damage growing population cause to the environment   b) with population growth     c) is complex and controversial     d) beyond the water’s ability to renew itself e) includes deforestation and desertification    

2. Complete these word combinations with verbs used in the text:

1. to …to be pessimistic

2. to…the free market and human ingenuity to develop new technology.

3. to…to soil erosion.

4. to…with ever-larger numbers and scarce resources.

5. to…the list of environmental problems by growing population

 

3. Write questions to these answers:

1. Any population increase often means putting more land under cultivation and raising the production per acre.

2. The loss of natural habitats to more and more cropland reduces the biological diversity of plants and animals.

3. As a result of the higher demand energy suppliers are mining more coal and building more dams.

4. Demographers predict the population of Mexico City will grow to more than 30 billion people.

5.The acid rains damages forest life.

 

4.Translate into English:

1. Для начала, я хотел бы сказать, что главной темой обсуждения сегодня является вопрос влияния роста населения на окружающую среду.

2. Не удивительно, что среди экологов и биологов есть оптимисты и пессимисты.

3.Несмотря на тот факт, что планета на сегодняшний день перенаселена, экономисты верят в то, что свободный рынок и человеческая изобретательность могут добиться развития новых технологий, которые помогут разрешить проблему нехватки природных ресурсов.

4. Любое увеличение населения значит и увеличение количества земель, отводимых под разведение сельскохозяйственных культур.

5.Потребление воды, естественно, увеличивается с ростом населения.

 



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