New genetic analysis has revealed that many Amazon tree species are likely to survive human-made climate warming in the coming century, contrary to previous findings that temperature increases would cause them to die out. A study,
1 in the latest edition of Ecology and Evolution, reveals the
2 age of some Amazonian tree species -- more than 8 million years -- and
3 shows that they have survived previous periods as warm as many of the global warming imagined periods
4 for the year 2100.
The authors write that, having survived warm periods in the past, the trees will
5 survive future warming, provided there are no other major environmental changes.
6 extreme droughts and forest fires will impact Amazonia as temperatures
7 , the trees will stand the direct impact of higher temperatures. The authors
8 that as well as reducing greenhouse gas emissions to minimize the risk of drought and fire, conservation policy should remain
9 on preventing deforestation（采伐森林）for agriculture and mining.
The study disagrees with other recent researches which predicted tree species’ extinctions
10 relatively small increases in global average air temperatures.
Study co-author Dr Simon Lewis (UCL Geography) said the
11 were good news for Amazon tree species, but warned that drought and over-exploitation of the forest remained major
12 to the Amazon’s future.
Dr Lewis said: “The past cannot be compared directly with the future. while tree species seem likely to
13 higher air temperatures than today, the Amazon forest is being transformed for agriculture and
14 , and what remains is being degraded by logging, and increasingly split up by fields and roads.
“Species will not move as freely in today’s Amazon as they did in previous warm periods, when there was no human
15 . Similarly, today’s climate change is extremely fast, making comparisons with slower changes in the past
16 .”
“With a clearer
17 of the relative risks to the Amazon forest, we
18 that direct human impacts -- such as forest clearances for agriculture or mining -- should remain a key point of conservation policy. We also need more aggressive
19 to reduce greenhouse gas emissions in order to make minimum the risk of drought and fire impacts and
20 the future of most Amazon tree species.”
| 小题1: | | A．advertised | B．described | C．published | D．presented |
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| 小题2: | | A．frightening | B．surprising | C．exciting | D．interesting |
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| 小题4: | | A．assess | B．confirm | C．forecast | D．promise |
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| 小题5: | | A．particularly | B．probably | C．merely | D．possibly |
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| 小题6: | | A．Since | B．Although | C．When | D．If |
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| 小题7: | | A．rise | B．change | C．drop | D．end |
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| 小题8: | | A．consider | B．decide | C．guarantee | D．recommend |
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| 小题9: | | A．based | B．built | C．focused | D．made |
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| 小题10: | | A．in relation to | B．in response to | C．in reply to | D．in reference to |
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| 小题11: | | A．findings | B．thoughts | C．inventions | D．writings |
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| 小题12: | | A．threats | B．disadvantages | C．embarrassments | D．instructions |
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| 小题13: | | A．accept | B．tolerate | C．permit | D．Require |
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| 小题14: | | A．farming | B．planting | C．catering | D．mining |
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| 小题15: | | A．power | B．influence | C．desire | D．violence |
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，B正确；从t =0到t =4s间甲的速度一直为正，即一直朝着正方向运动，C错误；图像的斜率表示物体运动的加速度，而斜率的正负表示方向，故从图中可得两者的斜率都为负，即加速度都是向负方向运动；D正确；