Climate change connected with the reduction of wetlands at the source of the country’s two longest rivers, the Yangtze and the Yellow, has reduced the volume of water flowing into them, scientists said.

Scientists studied changes over past 40 years to the wetlands on the cold Qinghai-Tibet Plateau in west China where the two rivers have their sources.

They found the wetlands on the plateau have shrunk（減少）more than 10 percent over the past four years. The wetlands at the source of the Yangtze have suffered the most, decreasing by 29 percent.

About 17.5 percent of the small lakes at the source of the Yangtze have dried up, the scientists said.

“The wetland plays a key role in holding water and changing the water volume of the rivers, ” Wang Xugen, a researcher, said.

“The reduction of the wetland on the plateau is closely connected with global warming, ” Wang said, adding that even though rainfall has increased in the area, the reduction of the wetland has reduced the flow of the Yangtze and the Yellow.

Records by the weather station at the head of the Yangtze showed yearly rainfall at its source increased from 260mm during 1991-2000 to 323 mm in the period 2001-2006.

“But the increased rainfall didn’t lead to more water’s flowing into the rivers because the evaporation（蒸發(fā)）was so fast as a result of global warming, ”Li Shijie, a researcher, said.

Another study showed global warming had caused glaciers to get smaller, frozen earth to melt, grasslands to turn yellow and rivers to dry up.

The Qinghai- Tibet Plateau used to have 36000 glaciers covering an area of 50,000 sq km. In the past 100 years, their area has been reduced by 30 percent.

1．According to the passage, the true statement of the following is that         .

       A．the wetlands at the source of the Yellow have decreased by 29percent.

       B．there’s no more water in about 17.5 percent of the small lakes at the source of the Yangtze`

       C．the reduction of the wetland on the plateau has nothing to do with global warming.

       D．yearly rainfall has increased from 260 mm to 323 mm in the past 15 years.

2．Which of the following is NOT the result of global warming?

       A．Frozen earth melts.                              B．Evaporation becomes faster.

       C．Sea level rises.                                     D．Plants grow better in greenhouses.

3．The area that the glaciers of the Qinghai-Tibet Plateau cover is now about         sq km.

       A．35,000                B．12,000                C．15,000                D．17,000

4．In the passage,         plays a most important part in holding water and changing the volume of the rivers.

      A．yearly rainfall                                      B．the evaporation

       C．the wetland                                         D．climate change

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科目：高中英語(yǔ) 來(lái)源：同步題 題型：閱讀理解

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     Climate scientists hit back at disbelievers yesterday with a new study which brought about the evidence
for man-made global war ming was"stronger than ever".
     After analyzing more than 100 scientific papers published in the last few years, a team of British
researchers say there is an"in creasingly small possibility" that the world is warming up because of natural
variations (變動(dòng)) in climate.
     Instead, man-made global warming-caused by the burning of fossil fuels-is making its mark on every
continent and ocean, they say.
     The studies used computer models to see whether changes in air temperature, sea ice, sea temperature,
wetness, rainfall and ocean saltiness recorded in the last 50 years could be explained by nature.
     Since 1980,the average global temperature has increased by around0.5℃,they found. The same warming
pattern was also found deep in the world's oceans.
     Natural forces such as volcanic eruptions and returning chan ges in the brightness of the sun could not
explain what was happen- ing to the world's climate, Dr Stott said.
     The sun's output had actually fallen over the last 50 years, he said.
     Even if the sun had got warmer over the last few decades-as some skeptics say-both the upper and lower
layers of the atmos phere should have got hotter.
     However, in the last 50 years the lower atmosphere has warmed while the upper atmosphere has actually
cooled, Dr Stott said.
     Drier parts of the world are getting drier, while wetter areas are getting more rain-a finding in agreement
with man-made climate change, the report found.
     And the amount of mid summer sea ice in the Arctic is also declining over time-even with the natural
yearly variations, the study found.
     The study comes along with growing public doubt about climate change.
1. With enough evidence the climate scientists prove _____.
A. global warming is disappearing recently
B. mankind isn't to blame for global warming
C. mankind is to blame for global warming
D. global warming will disappear sooner or later
2. What caused the global warming according to the British researchers?
A. Frequent volcanic eruptions across the world.
B. The increase of the brightness of the sun.
C. The warming pattern of the world's oceans.
D. The burning of fossil fuels by the human being.
3. The underlined word "skeptics" in Paragraph 8 refers these people who_____.
A. believe that mankind is to blame for global warming
B. believe global warming will disappear sooner or later
C. doubt the global warming will disappear sooner or later
D. doubt the global warming is caused by humankind
4. What can we infer from the last sentence of the passage?
A. The study has made the public live in a terrible dream at present.
B. Many people don't believe the study of the British researchers now.
C. The public have been used to the climate changes these years.
D. The result of the study comes from the opinions of the public.

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