英语六级(CET6)阅读理解模拟练习题及答案(8)

　　Before anyone can honestly care how important it is to protect marine habitats（生活环境）, one needs to appreciate the vast quantities of marine life that exists in the ocean. It is hard for some people to relate to something they never see. However, it makes sense that the vast expanse of water and its inhabitants, covering 70% of the planet, affects us all.

　　Most marine animals are found near coral reefs. These colorful underwater forests naturally spring to mind with the mention of scuba（水中呼吸器）diving or underwater life. Coral reefs are constructed by living plants and animals, primarily corals that surround their small anemone （海葵）-like tentacles in a hard skeleton that forms much of the reef structure.

　　They generally occur in clear, tropical or semi-tropical seas to a depth of approximately 100 meters （328 feet）. Coral reefs fringe approximately one sixth of the worlds coastlines and are the biologically richest of all shallow-water marine ecosystems. They support as many as 1 million species of animals and plants, but only a small fraction have been described. Among the best known groups are at least 5,000 species of fish, over 10,000 species of mollusk （软体动物） and more than 800 species of reef-building corals.

　　Corals are not only important to fish. Reefs are important to the human population for a wide variety or reasons: for one, they are a food source. A majority of people make their living fishing near coral reefs and an even larger part of population enjoys eating some of the catch. Unfortunately, if current trends of over-fishing continue, and we deplete fisheries as fast as we are, then this food source will eventually run out. Scientific evidence shows that 90% of top predators in the ocean are now extinct because of over-fishing-predatory fish include anything salmon sized and above all the way through sharks. On the other hand, killing off the grazing species of fish at reefs allows algae to build up, which in turn kills the coral. With 30% of oceanic fish making their home near coral reefs at one time or another, reefs are essential in maintaining a healthy fish population and many of the fish maintain the coral in return. Sustainable fishing is a must.

　　Corals arent only a food source. There is also a clear connection between tsunamis（海啸）and storm events having a much greater impact on eroding coastlines than healthy ones. Healthy reefs protect coastlines from the damage of massive waves. During the recent tsunami in Indonesia, for example, coastlines protected by reefs and mangrove forests remained intact and experienced much less impact than coasts that did not have reefs.

　　Pollution is a major threat to the ocean. Pollution comes in many forms and shapes, but most have one thing in common: Almost all ocean pollutants stem from land based human activity. Waste produced on land eventually finds its way to the ocean. It is not uncommon to find beaches littered with plastic bags and bottles that finally came to rest on shores. Rivers carry dirt, oils, sewage and chemicals out to sea. Garbage also finds its way to ocean. Seeing plastic bags floating around the water instead of fish is not a pretty sight. Washed up garbage on the sand will definitely ruin a nice beach vacation. With many third-world countries relying on tourism for income, it is important to maintain the ocean and beaches in as pristine a condition as possible.

　　Chemicals are constantly absorbed by the ocean. Chemicals have a drastic effect on fish populations and the fishing industry. Chemicals absorbed by animals at sea will also harm the human population that consumes them. Mercury is a chemical now commonly found in larger predatory fish such as tuna and shark. It occurs naturally in the environment and also can be released into the air through industrial pollution. Mercury falls from the air and can accumulate in streams and oceans. Bacteria in the water cause chemical changes that transform the mercury into methylmercury. It is this type of mercury（水银, 汞） that can be harmful to unborn babies and young children. Fish absorb the methylmercury as they feed in these waters. Methylmercury builds up in the tissue of some types of fish and shellfish more than others depending on what the fish eat.

　　High levels of mercury can poison the human body, have adverse effects on the nervous system and prevent a baby from developing normally in the womb. This is just one of the harmful chemicals that are actively absorbed by the ocean. Those of us who enjoy the occasional tuna salad sandwich or swordfish steak have been absorbing natural and industrial chemicals from the meat for a few years now suffer a lot.

　　Another chemical pollutant is carbonic acid. Atmospheric CO2 is absorbed by the ocean and reacts with the seawater to form carbonic acid-this makes the ocean more acidic and intolerable to a variety of species. The shells of living mollusks have even been known to dissolve in very acidic areas of the ocean. Sea creatures such as corals, shell fish, sea urchins and star fish are likely to suffer the most because higher levels of acidity makes it difficult for them to form and maintain their hard calcium carbonate （碳酸钙） skeletons and shells. For example, even under the low predictions for future carbon dioxide emissions into the atmosphere, the combined effects of climate change and ocean acidification mean that corals could be rare on tropical and subtropical reefs, such as the Great Barrier Reef, by 2050.

　　Some poisons are intentionally released into the water. Cyanide（氰化物）or pesticides are released in designated areas known to harbor fish and the stunned fish are scooped up in nets and sorted. Even though the poisons dont always kill the fish, they destroy smaller organisms including the coral reef building animals. Weve already lost 20-30% of all coral reefs. If we continue to impact the ocean like we are, another 50% of coral will die off within the next decade.

　　Obviously over-fishing and pollution will always be a problem. The solution lies in limiting activities that harm the ocean even though the problem will never be completely eliminated. Certain fishing techniques are devastating to marine environments and often unnecessary. Blasting is an example. This technique involves bombs that are detonated at sea in the hopes that the fish killed float to the surface for easy collection. Bottom trawling（拖网捕鱼）destroys massive amounts of deep sea ecosystems, killing the habitats of the animals they are fishing for. It is fishing practices like these that need improvement.

　　Controlling the amount of gases released into the atmosphere poses a more difficult problem. The good news is that there is a potential solution. Two effective techniques for limiting CO2 emissions would be, （1） to replace fossil fuels with energy sources that do not emit CO2, and （2） to use fossil fuels more efficiently. Alternative energy sources that do not emit CO2 include the wind, sunlight, nuclear energy, and underground steam. Devices known as wind turbines can convert wind energy to electric energy. Solar cells can convert sunlight to electric energy, and various devices can convert solar energy to useful heat. Geothermal power plants convert energy in underground steam to electric energy.

　　Fossil fuels are a limited resource as it is and research is currently underway in the hopes of finding alternative （and more environmentally friendly） fuel sources. Until research comes up with less expensive alternative fuels, fossil fuels will continue to be used as the worlds primary energy source.

　　A few years ago, the idea of an animal surviving the intense pressures of the deep sea was inconceivable. Today, it is a known fact that animals manage to survive at such depths. In fact, the deepest fish on record was found at 27,460 ft （8,370 meters） below sea level. Unfortunately, with current trends in pollution and deep sea fishing, many species may become extinct before they are even discovered! It is important to protect existing marine habitats, not only to protect a major resource of everything from food to tourism to coastal protection, but to ensure the survival of the creatures that make the world such a fascinating place.

　　1. According to the passage, how many species of animals and plants do coral reefs support?

　　A） They support 800 species of animals and plants.

　　B） They support 5,000 species of fish and plants.

　　C） They support as many as 1 million species of animals and plants.

　　D） They support over 10,000 species of mollusk and plants.

　　2. Why are coral reefs essential to human beings?

　　A） Because they provide a means of living and source of food for human beings.

　　B） Because they provide a tourist destination for human beings.

　　C） Because they provide a place for human beings to fish.

　　D） Because they provide a kind of entertainment for human beings.

　　3. If in a healthy state, coral reefs can .

　　A） stop tsunamis and storm events from attacking the coastlines

　　B） protect coastlines from the damage of extraordinary waves

　　C） stop people from fishing ear the coral reefs

　　D） protect coastlines from peoples damage

　　4. What is said about humans activity as littering plastic bags and bottles?

　　A） It ca badly damage the coral reefs ear the coastline.

　　B） It can have impact on tourism of the developed countries.

　　C） It ca badly damage peoples life near the coastline.

　　D） It ca pollute the ocean and influence tourism.

　　5. When mercury falls into the ocean, it was converted to a chemical of more harmful nature that can endanger .

　　A） unborn babies and young children

　　B） adult women

　　C） the environment of the ocean

　　D） the coral reefs

　　6. Carbonic acid has the most serious impact on .

　　A） the human being

　　B） shell fish and star fish

　　C） tunas and sharks

　　D） marine mammals

　　7. People bomb certain area of the sea and the killed fish floating on the sea surface

　　A） can be collected easily

　　B） can harm the ocean

　　C） can pollute the environment

　　D） can damage peoples health

　　8. We ca wither find alterative energy sources or make better use of fossil fuels to reduce____________.

　　9. We are now researching to find alternative fuels that are more environmentally friendly and _________________.

　　10. We should protect the marine creatures as creatures themselves that have rights for survival, not simply as useful _______________.

文章梗概：

　　本文介绍了海洋及海洋生物的作用及其所受到的危害。首先介绍海洋的作用提供食物、旅游资源，海洋生物对海岸的保护。之后阐述了过度捕鱼造成的危害。接下来谈到了各种污染物对海洋及生物的影响，以及对人类的危害。最后指出我们应该保护海洋资源，确保海洋生物的生存。

　　答案解析：

　　1.由题干关键词Coral reefs和supports. . . animals and plants定位至第三段第三句They support as many as 1 million species of animals and plants, but only a small fraction have been described. 珊瑚礁供养着多达100万种动植物，但其中人们描述的仅有一小部分。由此可知选项C）正确。

　　2. 由题干关键词essential to human beings定位至第四段第三句A majority of people make their living fishing near coral reefs and an even larger part of population enjoys eating some of the catch. 选项A）是对该句的同义转述，故为正确答案。

　　3. 由题干关键词healthy state和coral reefs定位至第五段第三句Healthy reefs protect coastlines from the damage of massive waves. 健康的珊瑚礁可以保护海岸不受巨浪冲击的伤害。这说明珊瑚礁能降低风暴的危害程度，而A）说珊瑚礁能阻止风暴侵袭是错误的；C）和D）文中并未提及；B）中的extraordinary一词和massive同义，故为正确答案。

　　4. 由题干关键词littering plastic bags and bottles定位至第六段,该段主要阐述人类随意丢弃垃圾的行为会污染海洋，影响旅游业，尤其是第三世界国家的旅游业，却没有提及这种行为对珊瑚礁的影响。因此答案为D）。

　　5. 由题干关键词mercury和harmful定位至第七段倒数第三句It is this type of mercury that can be harmful to unborn babies and young children. 是这种水银可能对未出生的婴儿和幼儿有害。A）是该句的同义转述，故正确。

　　6. 由题干关键词carbonic acid定位至第九段第三句Sea creatures such as corals, shell fish, because higher levels of acidity makes it difficult for them to form and maintain their hard calcium carbonate skeletons and shells. 像珊瑚、贝类动物、海胆和海星这样的海洋生物容易受到最大的伤害，因为酸量较高的话会使它们难以形成和保养自身坚硬的碳酸钙骨骼和外壳。因此答案为B）。

　　7. 由题干关键词bomb certain area of the sea定位至倒数第四段倒数第三句This technique involves bombs that are detonated at sea in the hopes that the fish killed float to the surface for easy collection.意思是这项技术包含在海里实施爆炸，以此希望漂浮在海面上被炸死的鱼可以轻易地被收集起来。 由此可知A）正确。

　　8. 由题干关键词fossil fuels定位至倒数第三段第三句Two effective techniques for limiting CO2 emissions would be, （1） to replace fossil fuels with energy sources that do not emit CO2, and （2） to use fossil fuels more efficiently.由此可见，题干是对这句话的同义转述，据此，答案应为CO2 emissions.

　　9. 由题干关键词alternative fuels和more environmentally friendly定位至倒数第二段最后一句Until research comes up with less expensive alternative fuels, fossil fuels will continue to be used as the worlds primary energy source. 据此，答案应为less expensive.

　　10. 由题干关键词protect the marine creatures定位至最后一段最后一句It is important to protect existing marine habitats, not only to protect a major resource of everything from food to tourism to coastal protection. 无疑，protect后面就是答案，但是应该根据题干的含义进行简化。经分析可知，与海洋生物自身的生存相对比,它们作为食品、旅游和海岸保护资源都是从人类角度出发的，据此，可以把这些作用总结为resource to human being.