1 . Some scientists say that animals in the oceans are increasingly threatened by noise pollution caused by human beings.

The noise that affects sea creatures comes from a number of human activities. It is caused mainly by industrial underwater explosions, ocean drilling,and ship engines. Such noises are added to natural sounds. These sounds include the breaking of ice fields, underwater earthquakes, and sounds made by animals themselves.

Decibels(分贝) measured in water are different from those measured on land. A noise of one hundred and twenty decibels on land causes pain to human ears. In water, a decibel level of one hundred and ninety-five would have the same effect.

Some scientists have proposed setting a noise limit of one hundred and twenty decibels in oceans. They have observed that noises at that level can frighten and confuse whales.

A team of American and Canadian scientists discovered that louder noises can seriously injure some animals. The research team found that powerful underwater explosions were causing whales in the area to lose their hearing. This seriously affected the whales’ ability to exchange information and find their way. Some of the whales even died. The explosions had caused their ears to bleed and become infected.

Many researchers whose work depends on ocean sounds object to a limit of one hundred and twenty decibels. They say such a limit would mean an end to important industrial and scientific research.

Scientists do not know how much and what kinds of noises are harmful to ocean animals. However, many scientists suspect that noise is a greater danger than they believed. They want to prevent noises from harming creatures in the ocean.

3 . Japan said Tuesday that it would start pouring treated radioactive water (放射性废水) from the Fukushima nuclear power plant into the Pacific Ocean within two years. Officials in Tokyo said the water would be filtered and diluted (稀释) to safe levels first, but most locals remain firmly opposed to the plan. Protesters gathered outside Prime Minister Yoshihide Suga’s residence in downtown Tokyo to criticize the government’s decision.

More than a million tons of radioactive water is currently being stored at the Fukushima power plant in a massive tank farm big enough to fill 500 Olympic-sized swimming pools. The wastewater comes from water pumped in to cool the plant’s damaged reactors (反应堆). The government says it has simply run out of room to store all the water. The plan to dump the water into the ocean first came to light in the autumn of last year, when Japanese news reported anonymous (匿名的) officials said the decision had been taken.

On Tuesday, Suga said that after years of study, his scientific advisors had concluded that ocean discharge was the most possible way to cope with the wastewater. But the decision to pour Fukushima wastewater into the ocean has drawn fire from neighboring Asian countries and local fishermen along Japan’s coast.

China called the decision “extremely irresponsible,” and South Korea summoned (召唤) the Japanese ambassador in Seoul over the matter. “They told us that they wouldn’t release the water into the sea without the support of fishermen,” Kanji Tachiya, who leads a local cooperative of fisheries in Fukushima, told national broadcaster NHK ahead of the announcement on Tuesday. “We can’t support this move to break that promise and release the water into the sea unilaterally (单方面地).”

The actual release of water from the Fukushima plant will take decades to complete. Critics have called on Japan’s government to at least ensure that independent monitoring is in place to check the level of radiation in the poured water is safe for the environment.

4 . If humans were truly at home under the light of the moon and stars, we would go in darkness happily, the midnight world as visible to us as it is to the vast number of nocturnal (夜间活动) species on this planet. Instead, we are diurnal creatures, with eyes adapted to living in the sun’s light. This is a basic evolutionary fact, even though most of us don’t think of ourselves as diurnal beings. Yet it’s the only way to explain what we’ve done to the night: We’ve engineered it to receive us by filling it with light.

The benefits of this kind of engineering come with consequences — called light pollution — whose effects scientists are only now beginning to study. Light pollution is largely the result of bad lighting design, which allows artificial light to shine outward and upward into the sky. Ill-designed lighting washes out the darkness of night and completely changes the light levels — and light rhythms — to which many forms of life, including ourselves, have adapted. Wherever human light spills into the natural world, some aspect of life is affected.

In most cities the sky looks as though it has been emptied of stars, leaving behind a vacant haze (霾) that mirrors our fear of the dark. We’ve grown so used to this orange haze that the original glory of an unlit night — dark enough for the planet Venus to throw shadows on Earth — is wholly beyond our experience, beyond memory almost.

We’ve lit up the night as if it were an unoccupied country, when nothing could be further from the truth. Among mammals alone, the number of nocturnal species is astonishing. Light is a powerful biological force, and on many species it acts as a magnet. The effect is so powerful that scientists speak of songbirds and seabirds being “captured” by searchlights on land or by the light from gas flares on marine oil platforms. Migrating at night, birds tend to collide with brightly lit tall buildings.

Frogs living near brightly lit highways suffer nocturnal light levels that are as much as a million times brighter than normal, throwing nearly every aspect of their behavior out of joint, including their nighttime breeding choruses. Humans are no less trapped by light pollution than the frogs. Like most other creatures, we do need darkness. Darkness is as essential to our biological welfare, to our internal clockwork, as light itself.

Living in a glare of our own making, we have cut ourselves off from our evolutionary and cultural heritage — the light of the stars and the rhythms of day and night. In a very real sense, light pollution causes us to lose sight of our true place in the universe, to forget the scale of our being, which is best measured against the dimensions of a deep night with the Milky Way — the edge of our galaxy — arching overhead.

6 . Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the biggest is pollution. Pollution comes in many ways. We see it, smell it, drink it and even hear it.

Men have been polluting the earth. Many years ago, the pollution was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, men moved to another place.

Air pollution is now the most serious. Air makes people sick. And lots of people now are trying to use something to clear the air. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us become angry more easily.

Many countries are making rules to fight air pollution. They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air.

Pollution by SO2 is now the most dangerous kind of air pollution. It is caused by heavy traffic. It is true that if there are fewer people driving, there will be less air pollution.

Although most of the pollution is caused by us, we are the ones who can change the situation. The earth is our home. We must take care of it. And we must pay more attention to the information in pollution at the same time.

7 . Space is where our future is — trips to the Moon, Mars and beyond.    1     But, since our space journey started we have left so much trash (垃圾) there that scientists are now concerned that if we don’t clean it up, we may all be in great danger.

The first piece of space junk was created in 1964, when the American satellite Vanguard I stopped operating and lost its connection with the ground center.    2    

    3     The junk varies from tiny pieces of paint chipped off rockets to cameras, huge fuel tanks, and even odd items like the million-dollar tool kit that astronaut Heidemarie Stefanyshyn Piper lost during a spacewalk.

    4     Moreover, pieces of junk may crash with each other and break into pieces which fall back to the Earth.    5     Ground stations have been built to monitor larger pieces of space trash to prevent them from crashing into working satellites or space shuttles. Future plans include a cooperative effort among many nations to stop littering in space and to clean up the trash already there.

8 . In today’s world, almost everyone knows that air pollution and water pollution are harmful to people’s health. However, not all the persons know that noise is also a kind of pollution, and that is harmful to human health, too.

People who work and live under noisy conditions usually become deaf. Today, however, scientists believe that 10 percent of workers in Britain are being deafened by the noise where they work. Many of the workers who print newspapers and books, and who weave (织) cloth become deaf. Quite a few people living near airports also become deaf. Recently it was discovered that many teenagers in America could hear no better than 65-year-old persons, for these young people like to listen to pop music and most of pop music is a kind of noise. Besides, noise produced by jet planes or machines will make people’s life difficult and unpleasant, or even make people ill or even drive them mad.

It is said that a continuous noise of over 85 decibels (分贝) can cause deafness. Now the governments in many countries have made laws to control noise and make it less than 85 decibels.

In China, the government is trying to solve not only air and water pollution problems but also noise pollution problems.