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很像,非常像,几乎就是照这个改写的
LZ,麻烦再帮忙确认下,年轮那篇是不是这个呢? 第二篇树木年轮(原文原题已出) You can tell how old a tree is simply by countingits rings, which reflect the changing seasons. However, things are lessstraightforward when it comes to tropical trees, since there are no summers andwinters to mark the passage of time. Now scientists have worked out a simpleway to tell the age of trees from the tropics, according to Nature. Currently, factors such as the width of treerings in temperate zones are used to provide a detailed record of climateconditions for the past 1 000 years or so. But only a few types of trees in thetropics have visible rings: the variances between wet and dry seasons are tooslight to leave a distinguishable mark. Until now, scientists have depended onmeasurements of oxygen and carbon isotopes to determine their age, butPascalePoussart, a geochemist at Princeton University in New Jersey, and her colleagues,have shown that an apparently ring less Miliusa velutina tree(野独活)from Thailand does have rings... they're justinvisible. Using X-ray beams focused on wood samples, theresearchers looked at calcium, a mineral that trees take up during their maingrowing season. They revealed annual peaks dating back to 1909.Although theresults were in line with carbon isotope measurements,(关于新方法,何者是对的) the calcium method is much quicker. "It took us just one afternoon in thesynchrotron to produce the record," (方法最大的优点) says Poussart. "The isotope record costfour months of lab time." The team doesn't yet know whether seasonalcalcium cycles are common, (如何使新方法普遍接受) or if the feature is specific to just a fewtypes of trees. And it is unclear whether periods of drought, or the modest andpatchy dry seasons that feature in some areas of the tropics, will make thesignal undecipherable. In search of answers, Poussart will be working withscientists at the Smithsonian Tropical Research Institute's Center for TropicalForest Science, who runs long-term forest monitoring programmers in Africa,Asia and Latin America. At the moment, much about tropical systems is amystery, so anything that helps measure time will make an importantcontribution to the understanding of tropical forest dynamics. 1.主旨题#提出一个新方法,并说明其有缺陷# 2.第二段与第一段:新老办法对比 参考答案:calcium方法没有炭氧法那么well-established. 3.下列哪一个是undermine第一段所说"热带树林 is too subtle to 显示气候的迹象"? 参考答案:在泰国地区,发现了三种新型态的热带树林,他们的年轮痕迹是用肉眼就可以看出来的 4.下列哪种情况学者会比较支持第二段那个人calcium的方法 参考答案:如果知道季节在哪种情况下会对年轮辨识度影响较大 5.问文章最后一句话(这种collaboration)infer 参考答案:选对此方法需进一步验证其有效性 6.问从文章可以infer什么? 参考答案:方法可以测树的年龄 7.这种方法最大的优点 省时间 8.问关于这个科学家题出的新方法何者正确 Tree830224 7/13 Q1 If which of the following has been proved, P科学家的Cal方法will be widely accepted?(选项:It can be determined the drought season willmore affect decipher than dry seasons; all the tropical trees have been provedto be different with regard to seasonal calcium cycles;) Q2 主旨题:evaluate the reliability of a new method withregard to determining the climate change; Q3 which is true about the two methods? (选项:carbon method is more established than P’smethod; P has used x-ray to test carbon(这里注意是carbon, P的新方法是关注calcium),选项有很多都是carbon出现的,要当心;Carbon is more accurate in determining theage;…..) Q4 Which can be inferred from the passage?(选项:P’s method needs further study to check its efficiency;)-- by 会员 XYXB (2011/12/5 18:06:42)
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