朗阁雅思达人全球时事瞭望之气候.doc

朗阁雅思达人全球时事瞭望之气候Global Watch from an IELTS Perspective雅思阅读篇树木死亡和气候朗阁海外考试研究中心 【时事聚焦】近一个世纪，世界上森林覆盖面积大幅度锐减，除了人为因素的大量砍伐，也有相当数量的树木由于自然气候死亡。自然气候的改变带来的炎热和干旱导致了世界上越来越多的树木奄奄一息。下面我们就来看一则建立在几十篇科学文献基础上，有关此话题的最新报道。Tree Deaths Linked To Climate ChangeHot and dry conditions triggered by climate change are killing the worlds trees, according to a new report which examines dozens of scientific articles on the subject.Stanford University graduate student William Anderegg has seen this forest die-off firsthand.His doctoral thesis documents the impact of drought on trembling aspen, the most common tree in North America.“These are complete hillsides of trembling aspens that are dying off, Anderegg says. And when the main tree in a forest goes, you tend to see a lot of the other species, especially the grasses and the wild flowers, tend to disappear as well. But you lose a lot of those species from those forests.”Changing ecologyWith colleagues from Stanford and North Arizona State University, Anderegg co-authored the new report which presents a picture of accelerating worldwide tree deaths that appear to be linked to changes in the global climate.Anderegg says these changes, triggered by rising levels of heat-trapping gases in the atmosphere, are stressing the worlds forests.“One of the ways that we expect climate change to increasingly play out in forests is through these widespread tree mortality events where you stress the trees enough that you essentially push a whole region of them off the edge and in fact what happens afterwards, after a forest dies from drought is every bit as important and in some sense matters more to humans who rely on forests.”Trees provide a range of ecological services. They hold soil in place, help purify water and shelter species. They are valued for timber and tourism. When trees die, the ecology and hydrology of a forest change, which in turn promotes insect infestation and fire.This can result in long-term shifts in the areas dominant species and may even trigger a transition to a different ecosystem, such as grass land.Devastating consequenceAnderegg says the most devastating consequence may be that the changing forests, in turn, will start affecting the global climate.“Because forests do a lot to stabilize the climate and to store carbon and when they start to die off, you can actually have forest die-off accelerate climate change, he says. You get into a vicious cycle.”This is especially troubling for Anderegg because trees, which cover 30 percent of the earths surface, absorb 25 percent of the climate-changing gases emitted into the atmosphere from cars, buildings and factories.Forest monitoringWhile scientists are getting better at tracking the effects of climate change on forests, data is still sparse. Anderegg says his study urges governments and specialists from many disciplines to support wide-scale forest monitoring.“It is not just ecologists, but we also need people working with satellites. We need people in government agencies. We need people on the ground to do this as well. Its unfortunately not something that just the scientific research community can pull off on their own.”Anderegg, whose research is published in Nature Climate Change, says a better understanding of how climate change is killing off the worlds forests can help shape better forest management, business decisions and policies.【热点话题】根据以上的这则研究报道，我们发现树木死亡的话题和雅思阅读考试有十分紧密的联系，雅思阅读话题中有很多都涉及到环保，生态，这在2012年1月-9月的考试中可见一斑。平时对这类话题的背景知识累积有助于考生更好地理解新文章。因为吸热气体在大气层中的不断增加，所以不仅是森林里的树木，野花和草类也逐渐消失。这样的后果会造成该地区生态系统的改变，转而再次影响全球气候。【难句词汇】雅思考生的阅读难点之一就是对词汇量和句型的掌握程度不同，如果学生的词汇量不足，那么文章将看不懂，我们从上文中就可以学到很多的句型和词汇。 Hot and dry conditions triggered by climate change are killing the worlds trees, according to a new report which examines dozens of scientific articles on the subject.定语后置修饰（过去分词短语作后置定语）l triggerv. 导致，引发l dozens of几十个 These are complete hillsides of trembling aspens that are dying off, the most common tree in North America.定语从句和同位语l tremblingadj. 颤抖的l aspenn. 白杨l die off死亡，消失 And when the main tree in a forest goes, you tend to see a lot of the other species, especially the grasses and the wild flowers, tend to disappear as well.条件状语从句，插入语l speciesn. 种类l wildadj. 野生的 One of the ways that we expect climate change to increasingly play out in forests is through these widespread tree mortality events where you stress the trees enough that you essentially push a whole region of them off the edge and in fact what happens afterwards, after a forest dies from drought is every bit as important and in some sense matters more to humans who rely on forests.定语从句，地点状语从句，主语从句l mortalityn. 死亡l droughtn. 干旱l in some sense在某种意义上l edgen. 边缘 When trees die, the ecology and hydrology of a forest change, which in turn promotes insect infestation and fire.时间状语从句、非限制型定语从句l ecologyn. 生态l hydrologyn. 水文学l infestationn. （害虫）出没，横行 Because forests do a lot to stabilize the climate and to store carbon and when they start to die off, you can actually have forest die-off accelerate climate change, he says. You get into a vicious cycle.原因状语从句，时间状语从句l stabilizev. 使稳定l acceleratev. 增加，加速l viciousadj. 凶猛的，恶劣的从以上这些内容中我们学到了很多的表达方式和句型，这样一来对于雅思阅读的理解力和速度的提高有很大的帮助。从文章结构上来看，本文是很明显的现象解释原因后果预测建议的行文模式。这和很多剑桥系列里的文章相似。文章中同时也涉及了许多生态，环保类的雅思高频词，比如stabilize, infest, mortality等等。朗阁海外考试研究中心分析发现，在剑桥雅思真题中也有相关类型的文章供考生阅读理解和训练：剑四Rainforest; 剑七Deforestation; 剑七The Little Ice Age, 以上三篇文章都是当下热点的环保类文章，考生可以精读加考题训练。【真题预测】根据刚才关于树木死亡和气候的原版文章，我们来练习一下雅思阅读的常考题型之是非无判断题：Do the following statements agree with the views of the writer in this passage?TRUE / FALSE / NOT GIVEN1. If a kind of species die off, the ecology of this region is likely changed also.2. Forests only serve as the role of storing carbon.3. The government is now carrying out specific programs to address this deteriorating phenomenon.