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LONDON: What could possibly be wrong with planting trees? The benefits are obvious; they  firm the soil, soak up (摄取) extra water and take carbon dioxide (二氧化碳) out of the atmosphere.

However, it now turns out that planting trees could add to global warming.

Tree roots do a great job of keeping soil firmly on the ground and out of the wind’s power. The problem is that some of those dust clouds play an important part in taking in carbon dioxide.

Huge dust storms blow out over the oceans from dry parts of North Africa and central Asia. Tons of dust are lifted and left as a thin film over the ocean surface. The dust fuels oceanic life.

Dust from China is carried east and left in the Pacific Ocean. If a tree-planting programme there is successful and the dust supply reduced, the final result may be that less carbon dioxide gets locked away in the ocean.

Andy Ridgwell, an environmental scientist from the University of East Anglia, has spent the past few years studying dust and says his work “shows clearly the complexity of the system and the importance of not tinkering(粗劣地修补) with it without understanding the results. For this reason the need is to focus(集中) on cutting carbon dioxide giving off rather than monkeying (瞎弄) about with the land surface.”

An American scientist, Robert Jackson, has shown that when native grassland areas are invaded(侵入) by trees, carbon is lost from the soil. “We are studying why the soil carbon disappears, but one theory is that trees do a lot more of their growing above ground compared to grasses, so less carbon goes directly into the soil from trees, ” says Jackson.

In wet areas of the world, the gain from trees absorbing carbon dioxide above ground seems to be outweighed(超过) by the loss of carbon from the soil below ground. Countries that plan to combat global warming by planting trees may have to think again.

Solutions to environmental problems are often more complex than they first appear, and understanding the Earth’s climate is a very great challenge.

1.People usually hold the opinion that_____________.

    A. huge dust storms can destroy carbon dioxide

    B. huge dust storms can destroy the oceans on the earth

    C. huge dust storms can’t do anything beneficial for man

    D. planting trees is the only way to control huge dust storms

2. Andy Ridgwell, the environmental scientist, believes that_____________.

    A. dust plays a more important part than trees

    B. trees shouldn’t have been planted in dry places

    C. carbon dioxide is harmful to everything on the earth

    D. environmental problems are more complex than expected

3. Robert Jackson’s experiment proves that_____________.

    A. grassland areas should be covered by forests

    B. trees hold more carbon than grasses

    C. carbon can turn grass into dust

    D. less carbon can make trees grow faster

 

【答案】

 

1.C

2.D

3.B

【解析】略

 

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科目:高中英语 来源:英语教研室 题型:054

Almost 50 years have passed since one-time beekeeper, Sir Edmund Hillary, became the first man in the world to conquer the world’s highest peak, Mt Everest. In an extraordinarily

   1   exposition (展览)Auckland Museum pays   2   to this great New Zealander, Sir Edmund Hillary: Everest and Beyond Exhibition at the museum until April 25.

  Hillary reached Mt Everest’s   3   on May 29, 1953—just in time   4   the Queen’s Conation (加冕典礼).

  Now 83 and   5   by New Zealand as its greatest   6   countryman, Sir Edmund, a Knight of the Garter, prefers to be called just   7   Ed. He and his wife June were guests of honor at the exhibition opening in February, coinciding(巧合)with the museum’s 150th birthday.

  Visitors are   8   into his adventure—packed and charitable world through a

   9   treasure chest of his memorabilia(大事记),from a well-worn passport to the ice

   10   he used to climb that mountain.

  A Nepalese schoolhouse, kitchen and Buddhist temple have been   11   to show the place he has   12   40 years of his charitable soul and money to   13   the Himalayan Trust, building schools, hospitals and all manner of infrastructure(基础设施)in the   14   stricken country.

  The exhibition also   15   Ed’s climbs in the Southern Alps, a tractor journey he

   16   to the South Pole in 1967 and a trip up the River Ganges by jet boat.   17   the exhibition closes it will go to the United States, to   18   Sir Edmund’s jubilee 50年节)year,

   19   a celebratory party in London and a   20   with his Sherpa friends in Kathmandu.

  1Asimple            Blarge           Cdetailed          Dgreat

  2Aattention           Brespect          Cadmiration        Dhonor

  3Atop              Bpeak           Cheight          Dlevel

  4Aat                Bof             Cfor            Dwith

  5Alooked upon       Bthought about    Clooked up         Dthought out

  6Aliving             Blive           Calive            Dlively

  7Ashort             Bplain           Cas              Dfor

  8Aput              Bpoured          Cled             Ddrawn

  9Aclear              Bdear            Creal            Dnew

  10Aknife              Baxe           Cfork             Dspear

  11Arecreated          Brecycled        Crecovered         Drepaired

  12Aspent           Btaken          Cdevoted          Dused

  13Aby             Bthrough         Cfor            Dfrom

  14Apoverty          Bstorm          Cdisaster          Dearthquakes

  15Acovers           Bshows         Ctells             Dexpresses

  16Apaid             Bdid            Cmade           Dtook

  17AWhile           BIf             CSince           DWhen

  18Asign             Bmark           Cdesign          Dcontinue

  19Abeginning with      Bjoining in       Cending up with    Dadding up to

  20Areunion          Brepetition       Creview           Drecovery

 

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