8."Plants were supposed to grow larger with increased carbon dioxide in the atmosphere,but changes in temperature,humidity and nutrient availability seem to have trumped the benefits of increased carbon dioxide,"said researchers from the National University of Singapore.
45percent of the species studied now reach smaller adult sizes than they did in the past.The researchers point out that warmer temperatures and changing habitats,caused by climate change,are possible reasons for the shrinking of creatures.
"We do not yet know the exact mechanisms involved,or why some organisms are getting smaller while others are unaffected,"the researchers said."Until we understand more,we could be risking negative consequences that we can't yet quantify."
The change was big in cold-blooded animals.Only two decades of warmer temperatures were enough to make reptiles (爬行動物) smaller.An increase of only 1℃caused nearly a 10percent increase in metabolism (新陳代謝).Greater use of energy resulted in tiny tortoises and little lizards.Fish are smaller now too.Though overfishing has played a part in reducing numbers,experiments show that warmer temperatures also stop fish growth..There is a recent report on warmer temperatures'negative effects on plankton (浮游生物),the base of the marine ecosystem.
Warm-blooded animals weren't immune from the size change caused by climate change.Many birds are now smaller.Mammals have been miniaturized too.Soay sheep are thinner.Red deer are weaker.And polar bears are smaller,compared with historical records.This isn't the first time this has happened in Earth's history.
55million years ago,a warming event similar to the current climate change caused bees,spiders and ants to shrink by 50to 75percent over several thousand years.That event happened over a longer time than the current climate change.
The speed of modern climate change could mean organisms may not respond or adapt quickly enough,especially those with long generation times.So,it is likely that more negative influences of climate change will be shown in the future.
32.Which of the following would be the best title for the passage?B
A.Why do some species become smaller?
B.Species become smaller as climate warms.
C.Climate change has many negative effects.
D.How does climate change in Earth's history?
33.The underlined word"trumped"in the first paragraph can be replaced by"A".
A.beaten
B.increased
C.strengthened
D.equaled
34.What can we learn from the passage?C
A.Cold-blooded animals become smaller because of the lack of food.
B.Birds have suffered more from climate change than fish.
C.Climate change has even affected plankton negatively.
D.The warming event has never happened in Earth's history before.
35.What is the author's attitude toward climate change?B
A.Optimistic.
B.Concerned.
C.Indifferent.
D.Confident.
分析 全文主要說明了氣候變暖導(dǎo)致許多生物個體變小這一現(xiàn)象.
解答 32.B,題目歸納題,全文主要說明了氣候變暖導(dǎo)致許多生物個體變小這一現(xiàn)象,因此B項(xiàng)最適合作本文標(biāo)題.
33.A,詞義猜測題,根據(jù)句中的but可知,畫線詞所在部分與畫線詞前面的內(nèi)容"大氣中二氧化碳的增加將使生物個體變大"是轉(zhuǎn)折關(guān)系,從而可以推測氣溫、濕度、營養(yǎng)等的變化對生物的影響戰(zhàn)勝了二氧化碳增加的好處,即實(shí)際上生物個體變小了,故答案為A.
34.C,細(xì)節(jié)理解題,根據(jù)第四段最后一句"There is a recent report on warmer temperatures'negative effects on plankton(浮游生物),the base of the marine ecosystem."可知,氣候變化已對浮游生物產(chǎn)生了有害影響.
35.B,態(tài)度觀點(diǎn)題,根據(jù)文章最后一句的"So,it is likely that more negative influences of climate change will be shown in the future."可知,作者對氣候變暖這一現(xiàn)象有些擔(dān)憂.
點(diǎn)評 解答任務(wù)型閱讀理解題,首先對原文材料迅速瀏覽,掌握全文的主旨大意.因?yàn)殚喿x理解題一般沒有標(biāo)題,所以,速讀全文,抓住中心主旨很有必要,在速讀的過程中,應(yīng)盡可能多地捕獲信息材料.其次,細(xì)讀題材,各個擊破.掌握全文的大意之后,細(xì)細(xì)閱讀每篇材料后的問題,弄清每題要求后,帶著問題,再回到原文中去尋找、捕獲有關(guān)信息.最后,要善于抓住每段的主題句,閱讀時,要有較強(qiáng)的針對性.對于捕獲到的信息,要做認(rèn)真分析,仔細(xì)推敲,理解透徹,只有這樣,針對題目要求,才能做到穩(wěn)、準(zhǔn).