TF阅读真题第974篇Endangered Coral Reefs

 

题目：

Endangered Coral Reefs

 

 

Reef-building corals are made by polyps (tiny sea animals) that build on the skeletal remains of previous generations providing habitat for many species of plants and fish. Corals have persisted for many millions of years but are now under serious threat from a wide range of human disturbances, Overfishing constitutes a significant threat, as an eighth of the world’s population-roughly 875 million people-live within 100 kilometers of a coral reef. Most of these people live in developing countries and island nations and depend greatly on fish obtained from local coral reefs as a food source. Overfishing leads to other harmful fishing practices. Once the large fish are removed from a coral reef, it becomes increasingly difficult to make a living harvesting the more elusive and lower-value smaller fish that remain. Fishers thus resort to more destructive techniques such as exploding parts of the reef and scooping up the dead and stunned fish that float to the surface.

The human threats to coral reefs discussed above are local or regional in scale. The ultimate peril to coral reefs is planet-wide in scale-ocean warming and acidification resulting from human-induced climate change. Corals are very sensitive to sea temperature, and small increases above normal summer-maximum temperature result in stress.Temperature-stressed corals undergo “bleaching,” in which they expel the zooxanthellae (a type of algae) from their tissues; zooxanthellae provide the corals with essential nutrients and are also responsible for the colors of many corals. Without the zooxanthellae, the coral tissues become transparent and reveal the white-imestone supporting skeleton beneath. lf temperature stress is of low level and short duration, corals can reacquire their zooxanthellae and survive, although they may be more susceptible to other stresses, such as disease. Highly temperature-stressed corals are not able to reacquire zooxanthellae sufficiently rapidly, and without them they die.

Occasional, small-scale episodes of coral bleaching are a natural phenomenon of coral reefs. However, coral bleaching events have been occurring with much greater frequency and intensity in recent decades, as extreme sea temperatures occur more frequently. A major mass-bleaching event in 1998 killed an estimated 16 percent of all corals on the planet, with 60 to 90 percent of all corals dying in the central and western Indian Ocean. About three-quarters of these affected reefs were able to recover to some extent. Modeling of future sea-surface temperatures, combined with knowledge of coral physiology, suggests that by the 2050s severe coral-bleaching events will be occurring just about every year in almost all coral reef systems on the planet.

The increasing concentrations of carbon dioxide in the atmosphere are not only causing ocean warming but are also making seawater more acidic. In the near term, ocean acidification makes it more difficult for corals to manufacture their calcium carbonate skeletons. To make their skeletons, corals need to combine calcium ions and carbonate ions dissolved in the surrounding seawater.

However, acids react with carbonate ions, converting them into bicarbonate ions, leaving fewer available to the coral. The corals thus have to expend more energy to produce their skeletons, which slows their growth and causes stress, making them more susceptible to other stresses, such as temperature and disease. Continued acidification will eventually cause corals, and other marine organisms with calcium carbonate structures, to stop growing altogether and, at some point, cause their skeletons to slowly dissolve.By 2030, atmospheric carbon-dioxide levels will reach at least 450 parts per million (ppm). At this level it is predicted that coral growth will be severely reduced. By 2050, carbon-dioxide levels will be around 500 ppm. At this level, only a few areas of the ocean will be suitable for reef-building corals to survive.

In the face of such a variety of human-related regional and planet-wide impacts, the overall health of coral reef systems is deteriorating rapidly, with the latest assessment being that 19 percent of the planet’s natural coverage of coral reefs has been permanently lost, another 15 percent is likely to disappear within the next 10 to 20 years, and another 20 percent is under threat of loss in 20 to 40 years. Thus, in the not-too-distant future, more than half of the planet’s coral reefs appear destined to disappear.

In the face of such a variety of human-related regional and planet-wide impacts, the overall health of coral reef systems is deteriorating rapidly, with the latest assessment being that 19 percent of the planet’s natural coverage of coral reefs has been permanently lost, another 15 percent is likely to disappear within the next 10 to 20 years, and another 20 percent is under threat of loss in 20 to 40 years. Thus, in the not-too-distant future, more than half of the planet’s coral reefs appear destined to disappear.

 

 

 

 

 

1

Reef-building corals are made by polyps (tiny sea animals) that build on the skeletal remains of previous generations providing habitat for many species of plants and fish. Corals have persisted for many millions of years but are now under serious threat from a wide range of human disturbances, Overfishing constitutes a significant threat, as an eighth of the world’s population-roughly 875 million people-live within 100 kilometers of a coral reef. Most of these people live in developing countries and island nations and depend greatly on fish obtained from local coral reefs as a food source. Overfishing leads to other harmful fishing practices. Once the large fish are removed from a coral reef, it becomes increasingly difficult to make a living harvesting the more elusive and lower-value smaller fish that remain. Fishers thus resort to more destructive techniques such as exploding parts of the reef and scooping up the dead and stunned fish that float to the surface.

The word “persisted” in the passage is closest in meaning to

Vocabulary Questions词汇题

Agrown

Bbecome stronger

Cspread

DLasted

2

Reef-building corals are made by polyps (tiny sea animals) that build on the skeletal remains of previous generations providing habitat for many species of plants and fish. Corals have persisted for many millions of years but are now under serious threat from a wide range of human disturbances, Overfishing constitutes a significant threat, as an eighth of the world’s population-roughly 875 million people-live within 100 kilometers of a coral reef. Most of these people live in developing countries and island nations and depend greatly on fish obtained from local coral reefs as a food source. Overfishing leads to other harmful fishing practices. Once the large fish are removed from a coral reef, it becomes increasingly difficult to make a living harvesting the more elusive and lower-value smaller fish that remain. Fishers thus resort to more destructive techniques such as exploding parts of the reef and scooping up the dead and stunned fish that float to the surface.

It can be inferred from paragraph 1 that overfishing commonly occurs near coral reefs in part because

 

Factual Information Questions事实信息题

 

Athe population of people who live near coral reefs is increasing rapidly

Bthe fish living near coral reefs are of greater commercial value than most other fish

Cthe water around coral reefs is clear, which makes the fish easy to find

Dmany people who live near coral reefs cannot obtain enough food to support themselves from other sources

3

Reef-building corals are made by polyps (tiny sea animals) that build on the skeletal remains of previous generations providing habitat for many species of plants and fish. Corals have persisted for many millions of years but are now under serious threat from a wide range of human disturbances, Overfishing constitutes a significant threat, as an eighth of the world’s population-roughly 875 million people-live within 100 kilometers of a coral reef. Most of these people live in developing countries and island nations and depend greatly on fish obtained from local coral reefs as a food source. Overfishing leads to other harmful fishing practices. Once the large fish are removed from a coral reef, it becomes increasingly difficult to make a living harvesting the more elusive and lower-value smaller fish that remain. Fishers thus resort to more destructive techniques such as exploding parts of the reef and scooping up the dead and stunned fish that float to the surface.

According to paragraph 1, fishers have adopted destructive practices such as exploding parts of reefs because these practices

 

Factual Information Questions事实信息题

 

Adiscourage fish from hiding beneath reefs

Ballow fishers to catch the smaller fish that remain near reefs

Cimprove fishers’ ability to catch fish using traditional fishing techniques

Dimprove fishers’ ability to catch the valuable fish that live in surface waters

4

The human threats to coral reefs discussed above are local or regional in scale. The ultimate peril to coral reefs is planet-wide in scale-ocean warming and acidification resulting from human-induced climate change. Corals are very sensitive to sea temperature, and small increases above normal summer-maximum temperature result in stress.Temperature-stressed corals undergo “bleaching,” in which they expel the zooxanthellae (a type of algae) from their tissues; zooxanthellae provide the corals with essential nutrients and are also responsible for the colors of many corals. Without the zooxanthellae, the coral tissues become transparent and reveal the white-imestone supporting skeleton beneath. lf temperature stress is of low level and short duration, corals can reacquire their zooxanthellae and survive, although they may be more susceptible to other stresses, such as disease. Highly temperature-stressed corals are not able to reacquire zooxanthellae sufficiently rapidly, and without them they die.

According to paragraph 2, which of the following poses the greatest danger to the continued existence of coral reefs?

 

Factual Information Questions事实信息题

 

ANaturally occurring climate change over time

BOverfishing

CHuman-caused changes affecting the oceans

DIncreases in diseases that cause corals to expel zooxanthellae

5

Occasional, small-scale episodes of coral bleaching are a natural phenomenon of coral reefs. However, coral bleaching events have been occurring with much greater frequency and intensity in recent decades, as extreme sea temperatures occur more frequently. A major mass-bleaching event in 1998 killed an estimated 16 percent of all corals on the planet, with 60 to 90 percent of all corals dying in the central and western Indian Ocean. About three-quarters of these affected reefs were able to recover to some extent. Modeling of future sea-surface temperatures, combined with knowledge of coral physiology, suggests that by the 2050s severe coral-bleaching events will be occurring just about every year in almost all coral reef systems on the planet.

The phrase “to some extent” in the passage is closest in meaning to

 

Vocabulary Questions词汇题

 

Acompletely

Bpartially

Crapidly

Dgradually

6

Occasional, small-scale episodes of coral bleaching are a natural phenomenon of coral reefs. However, coral bleaching events have been occurring with much greater frequency and intensity in recent decades, as extreme sea temperatures occur more frequently. A major mass-bleaching event in 1998 killed an estimated 16 percent of all corals on the planet, with 60 to 90 percent of all corals dying in the central and western Indian Ocean. About three-quarters of these affected reefs were able to recover to some extent. Modeling of future sea-surface temperatures, combined with knowledge of coral physiology, suggests that by the 2050s severe coral-bleaching events will be occurring just about every year in almost all coral reef systems on the planet.

According to paragraph 3, which TWO of the following are true about the bleaching of corals? To receive credit, you must select TWO answer choices.

 

Factual Information Questions事实信息题

 

Select 2 answers

AIt killed over half of all corals in 1998.

BIt sometimes occurs naturally.

CIt will probably happen almost every year by the middle of this century.

DIt causes an increase in the temperature of the surrounding water.

7

The increasing concentrations of carbon dioxide in the atmosphere are not only causing ocean warming but are also making seawater more acidic. In the near term, ocean acidification makes it more difficult for corals to manufacture their calcium carbonate skeletons. To make their skeletons, corals need to combine calcium ions and carbonate ions dissolved in the surrounding seawater. However, acids react with carbonate ions, converting them into bicarbonate ions, leaving fewer available to the coral. The corals thus have to expend more energy to produce their skeletons, which slows their growth and causes stress, making them more susceptible to other stresses, such as temperature and disease. Continued acidification will eventually cause corals, and other marine organisms with calcium carbonate structures, to stop growing altogether and, at some point, cause their skeletons to slowly dissolve.By 2030, atmospheric carbon-dioxide levels will reach at least 450 parts per million (ppm). At this level it is predicted that coral growth will be severely reduced. By 2050, carbon-dioxide levels will be around 500 ppm. At this level, only a few areas of the ocean will be suitable for reef-building corals to survive.

Why does the author provide the information that“ocean acidification makes it more difficult for corals to manufacture their calcium carbonate skeletons”?

 

Rhetorical Purpose Questions修辞目的题

 

ATo identify one result of ocean warming

BTo help explain why corals have become more susceptible to stresses

CTo suggest that the carbonate ions needed by corals are used up by other marine organisms

DTo support the point that carbon dioxide in the atmosphere is increasing

8

In the face of such a variety of human-related regional and planet-wide impacts, the overall health of coral reef systems is deteriorating rapidly, with the latest assessment being that 19 percent of the planet’s natural coverage of coral reefs has been permanently lost, another 15 percent is likely to disappear within the next 10 to 20 years, and another 20 percent is under threat of loss in 20 to 40 years. Thus, in the not-too-distant future, more than half of the planet’s coral reefs appear destined to disappear.

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

 

Sentence Simplification Questions句子简化题

 

AThe latest assessment is that human activities likely will be the cause of the deterioration in the health of coral reefs in the decades to come.

BThe planet’s natural coverage of coral reefs will be permanently lost within the next 40 years.

CWith so many human impacts, corals are quickly becoming more endangered, and in the coming decades even larger losses are likely to occur than the permanent losses suffered so far.

DBecause human activities increasingly have planet-wide effects, coral reefs will probably deteriorate more rapidly as time goes on.

9

The increasing concentrations of carbon dioxide in the atmosphere are not only causing ocean warming but are also making seawater more acidic. In the near term, ocean acidification makes it more difficult for corals to manufacture their calcium carbonate skeletons. To make their skeletons, corals need to combine calcium ions and carbonate ions dissolved in the surrounding seawater. However, acids react with carbonate ions, converting them into bicarbonate ions, leaving fewer available to the coral. The corals thus have to expend more energy to produce their skeletons, which slows their growth and causes stress, making them more susceptible to other stresses, such as temperature and disease. Continued acidification will eventually cause corals, and other marine organisms with calcium carbonate structures, to stop growing altogether and, at some point, cause their skeletons to slowly dissolve.⬛By 2030, atmospheric carbon-dioxide levels will reach at least 450 parts per million (ppm). ⬛At this level it is predicted that coral growth will be severely reduced. ⬛By 2050, carbon-dioxide levels will be around 500 ppm. ⬛At this level, only a few areas of the ocean will be suitable for reef-building corals to survive.

Look at the four squares ⬛ that indicate where the following sentence could be added to the passage

As atmospheric levels of carbon dioxide rise, coral growth and survival are predicted to decline.Insert Text Questions句子插入题

Where would the sentence best fit？Click on a square  sentence to the passage.

10

The coral reefs in the world’s oceans are facing multiple threats.

 

Prose Summary Questions概要小结题

 

Select 3 answers

ACoral reefs provide habitat for fish that are valuable to humans and are destroyed by some of the methods that the fishers use to catch them.

BBleaching events, in which corals release the algae that provide them with nutrition and their color, are happening more often as permanently because the zooxanthellae on which they depend are stressed by increasing water temperatures.

CHigh concentrations of carbon dioxide in the atmosphere have created conditions that make it harder for reef-building corals to grow and survive challenges.

DThe greatest human-caused losses of coral reefs have happened within 100 kilometers of the coast of developing island nations due to overfishing that destroys the coral reef ecosystem.

EMore than half of the planet’s coral reefs could disappear permanently because the zooxanthellae on which they depend are stressed by increasing water temperatures.

FIncreased levels of bicarbonate ions in the oceans have made ocean water more acidic, leaving coral too weak to reacquire zooxanthellae and repair themselves.