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  3. 共用题干 第二篇Don ' t Count on Dung" Conservationists（自然保护主义者）may be miscalculat...

共用题干 第二篇Don ' t Count on Dung" Conservationists（自然保护主义者）may be miscalculat...

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问题 共用题干
第二篇

Don ' t Count on Dung

" Conservationists（自然保护主义者）may be miscalculating the numbers of the threatened animals such
as elephants."say African and American researchers.The error occurs because of a flaw in the way that they
estimate animal numbers from the piles of dung（粪）the creatures leave behind.
The mistake could lead researchers to think that there are twice as many elephants as there really are in
some regions,according to Andrew Plumptre of the Wildlife Conservation Society(WCS)in New York.
Biologist Katy Payne of Cornell University in Ithaca,New York,agrees."We really need to know ele-
phant numbers and the evidence that we have is quite indirect,"says Payne,who electronically
tracks elephants.
Counting elephants from planes is impossible in the vast rainforests of Central Africa. So researchers of-
ten estimate elephant numbers by counting dung piles in a given area.They also need to know the rate at
which dung decays.Because it's extremely difficult to determine these rates,researchers counting elephants
in one region tend to rely on standard decay rates established elsewhere.
But researchers at the WCS have found that this decay rate varies from region to region depending on the
climate and environment. " Using the wrong values can lead the census astray（离开正道）,"says Plumptre.
He and his colleague Anthony Chifu Nchanji studied decaying elephant dung in the forests of Came-
roon.They found that the dung decayed between 55 and 65 per cent more slowly than the dung in the
rainforests of neighbouring Gabon.If researchers use decay rates from Gabon to count elephants in Cameroon,
they would probably find more elephants than are actually around."This could mean estimates in Cameroon
are at least twice as high as those derived from decay rates calculated locally,"says Plumptre."However
accurate your dung density estimate might be,the decay rate can severely affect the result."
Plumptre also says that the dung-pile census should be carried out over a region similar in size to an ele-
phant's natural range."The usual technique of monitoring only small,protected areas distorts numbers be-
cause elephants move in and out of these regions,"he says."If the elephant population increases within the
protected area,you cannot determine whether it is a real increase or whether it is due to elephants moving in
because they are being poached（入侵偷猎）outside."
Plumptre says that similar problems may also affect other animal census studies that rely on indirect evi--
dence such as nests,tracks or burrows（地洞）.
选项 Why do researchers estimate elephant numbers in an area by counting dung piles?
A:Because elephants are difficult to catch.
B:Because it is not possible to count elephants from a plane.
C:Because it is not possible to keep track of elephants.
D:Because elephants are shy animals.
答案B
解析threatened：有灭绝危险的。threatened animals：有灭绝危险的动物。endangered：有灭绝 危险的；有生命危险的。an endangered species：一个有灭绝危险的物种。frightened：受惊的。 killed：杀死了的。angered：激怒了的。
该题问的是：为什么研究人员通过数粪堆估计一个地区的大象数量？第四段第一、二 句说：从飞机上数中非广阔的赤道雨林中的大象是不可能的，所以研究人员通过数特定地区的粪堆估计该区域的大象数量。因此B是正确答案。
该题问的是：不可依据粪堆数估计大象数量的原因是什么？文章第五段第一句话是这 么说的：······这种取决于气候和环境的腐烂速率在不同的地区是不一样的。可见C是正确答案。
该题问的是：根据Plumptre的观点，选择粪堆普查的地区应符合什么样的条件？倒数 第二段提到了Plumptre的观点，即普查地区的大小应该和大象的自然生存区类似，不能过小以 至于象能自由出人，也就是说，必须足够大。
该题问的是：第六段的第一个词“He”指谁？一般情况下，代词回指的词必须离得很近。因此必定是“Andrew Plumptre "。
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