The scientists are searching for the s of the river. 查看更多

 

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The scientists are searching for the s______ of the river.

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DOES the Yangtze River still have baiji(白鳍豚), the graceful, grey dolphin with tiny eyes and a long narrow beak? Since November 6, a team of scientists from China, Switzerland, the United Kingdom, the United States, Germany and Japan have been searching for any sign of the freshwater dolphin on the middle and lower sections of the river. After six weeks, they came back empty-handed.

Wang Ding, of the Chinese Academy of Sciences, who is the head of the team, said he has seen a sharp decline in the baiji population over the past few decades. However, he is still unwilling to call the species extinct, and adds, “We will try every effort to save them as long as they are not found to be extinct.”

The baiji is shy and nearly blind and is one of the world’s oldest dolphin species. It dates back some 20 million years and is found only in the Yangtze. It's listed as one of the 12 most endangered animal species in the world.

Around 400 baiji were believed to be living in the Yangtze until the 1980s. 1 A 1997 survey spotted 13. Two years later their numbers were down to two.

The rapid disappearance of this dolphin over the past two decades coincided with the rapid expansion of economic development along the river. Research on some dead baiji collected in recent years showed that more than 90 per cent of the deaths were caused by human activities.

One reason is that over-fishing has cut the dolphin's food sources. Dams built along the river and neighbouring waterways have also kept them from swimming into and out of their habitats (居住地). Meanwhile, waste discharge (排放) has seriously polluted the river. And heavy river traffic has greatly reduced their living space.

The disappearance of the baiji would be the first instance of a large aquatic (水生的) mammal being driven to extinction since hunting killed off the monk seal around 1952.

1.Which of the following statements is true?

       A.The baiji is already extinct.

       B.Man is mainly responsible for the sharp decline in the number of baiji.

       C.There are about 12 baijis now in China.

       D.Human activities make the baiji almost blind.

2.What does the underlined sentence mean?

       A.People don’t find out the fact that the baiji is already extinct.

       B.We shouldn’t give up saving the baiji despite its limited number.

       C.Our effort is worthless if we can’t protect the baiji.

       D.Effort will lead to more population growth of the baiji.

3.Monk seal is talked about in the last paragraph in order to show        .

       A.baijis might be faced with the same threat as monk seals

       B.the monk seal is one of the large aquatic mammals

       C.mammals are more likely to be killed off

       D.the number of monk seals was very small

4.According to the passage, all the measures to help save baiji are mentioned except        .

       A.reducing the number of the ships traveling in the river

       B.building fewer dams along the river

       C.limiting and controlling the amount of fishing

       D.conducting more scientific research on the baiji

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Are Baiji Dolphin Extinct?

       Does the Yangtze River still have baiji the graceful, grey dolphin with tiny eyes and a long narrow beak?

    Since November 6, a team of scientists from China, Switzerland, the United Kingdom, the United States, Germany and Japan have been searching for any sign of the freshwater dolphin on the middle and lower sections of the river.After six weeks, they came back empty-handed.

    Wang Ding, of the Chinese Academy of Sciences, who is the head of the team, said.he has seen a sharp decline in the baiji population over the past few decades. However, he is still unwilling to call the species extinct, and adds, "We will try every effort to save them as long as they are not found to be extinct."

    The baiji is shy and nearly blind and is, one of the world's oldest.'dolphin species. It dates back some 20 million years and is found only in the Yangtze.It's listed as one of the  12 most endangered animal species in the world.

       Around 400 baiji were believed to be living in the Yangtze until the 1980s.A 1997 survey spotted 13.Two years later their numbers were down to two.

    The rapid disappearance of this dolphin over the past two decades coincided with(与……同时)the rapid expansion of economic development along the river. Research on some dead baiji collected in recent years showed that more than 90 percent of the deaths were caused by human activities.

   One reason is that over-fishing has cut the dolphin's food sources.Dams built along the river and neighboring waterways have also kept them from swimming into and out of their habitats. Meanwhile, waste discharge(排放) has seriously polluted the river. And heavy river traffic has greatly reduced their living space.

    The disappearance of the baiji would be the first instance of a large aquatic mammal(水生哺乳动物)being driven to extinction since hunting killed off the monk seal(僧海豹)around                                                                      1952.

56.Bajji dolphin used to live in        of the Yangtze River.

       A.upper sections                                         B.middle sections

       C.lower sections                                         D.middle and lower sections

57.The first paragraph shows writer's          .

       A.love of baiji                                                B.eagerness to write the passage

       C.anger for not having a baiji                           D. dissatisfaction with our government

58.Which of the following countries didn't join the action to search for baiji?

       A.England.               B.America.           C.Japan.             D.India

59. How many baiji dolphins were left by the end of last century?

       A.400                        B.13                 C.Atmost2              D.2

60.Which of the following reasons doesn't lead to the rapid disappearance of baiji dolphins? 

     A. Over-fishing.                                         B. Heavy Road Traffic.                 

       C. Dams built along the river.                      D. Waste discharge.

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阅读理解

  An ichthyologist is a scientist who studies fish.Most people who do this job say they love their work because it is very rewarding and varied.They work not only inside a laboratory, but also out in the field.Fieldwork includes traveling to river, oceans and lakes in order to collect information and specimens.Reading, writing and speaking are also very important to the job, Fish scientists need to read the research of other scientists.They must he able to write up their own research clearly so that others can follow it.They also need to be able to give lectures about their findings, so that they can spread knowledge.

  Ichthyologists who wish to specialize can choose any one of three areas of study.The first area is aqnaeuhure(水产养殖).This involves the study and practice of fish farming and management.Because it is a rather new study, there are very few job opportunities available.However, as there is so much to discover, many see it as an exciting area for a new ichthyologist to enter.The second area is fisheries science, which means working with a team of scientists to find out more about different fish species.The third area is about the protection of natural fish populations.This is very important today, given that many fish species are in danger of dying out because of the actions of humans.

  To become a successful fish scientist, you need to have a curious mind and be able to work on your own.You also need to be able to handle equipment and perform experiments;but most importantly, you must love fish.To become an ichthyologist, you will need to train at a university to pass a Bachelor of Science degree.For this, you will need to be good at mathematics, physical science and biology.Then, you will need to study for another year to complete an doctor’s degree in ichthyology.This doctor’s degree contains enormous work about all aspects of fish.You also need to complete a research paper.

(1)

What makes the jobs of ichthyologists so varied?

[  ]

A.

They study fish habits and collect information.

B.

They have to study science and mathematics.

C.

They work in fields as well as in laboratories.

D.

They read research papers written by others.

(2)

Which of the following statements is NOT true according to the passage?

[  ]

A.

An ichthyologist has an interesting and varied profession.

B.

Aquaculture is the study of fish protection.

C.

The life of an ichthyologist can involve lots of travel.

D.

A fish scientist needs to be independent and curious about things.

(3)

Who is most likely to become an ichthyologist?

[  ]

A.

Tom, because he likes fishing and outdoor sports.

B.

Jack, because he likes to travel and read adventure books.

C.

Jenny, because she likes science, mathematics and reading about dinosaurs.

D.

Jane, because she likes mathematics, science, biology and searching rock-pools.

(4)

The passage is probably written for _______.

[  ]

A.

university students

B.

science researchers

C.

fisheries experts

D.

fish farmers

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