[A] This re-grown "secondary" forest is crucial to the pair’s analysis. Within a few decades of land being abandoned, half of t

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问题     [A]  This re-grown "secondary" forest is crucial to the pair’s analysis. Within a few decades of land being abandoned, half of the original biomass has returned. Depending on what else is nearby, these new forests may then be colonized by animals and additional plants, and thus support many of the species found in the original forest.
    [B]   Elizabeth Bennett, of the Wildlife Conservation Society, an American conservation group, agreed and mentioned that for large birds and mammals, uncontrolled hunting for food and for trade is causing a phenomenon known as "empty-forest syndrome". She said that although many forests look healthy when viewed from a satellite, they are actually falling silent because many of their large animals have been removed for subsistence or profit.
    [C]  What everyone agreed, though, was that climate change is a threat. Even the optimistic Dr. Wright is worried because many tropical species evolved in an environment that has very little temperature variation, they are not equipped to cope with an increase of as little as 3°C, which is the sort of change that many climate scientists predict. He said that by the end of the century, 75% of tropical forests will be warmer than today, and what will remain in these hot, wet places is unknown.
    [D]   A rare piece of good news from the world of conservation: the global extinction crisis may have been overstated. The world is unlikely to lose 100 species a day, or half of all species in the lifetime of people now alive, as some have claimed. The bad news, though, is that the lucky survivors are tiny tropical insects that few people care about. The species that are being lost rapidly are the large vertebrates that conservationists were worried about in the first place.
    [E]   Dr. Wright and Dr. Muller-Landau therefore reckon that in 2030 reasonably unbroken tropical forest will still cover more than a third of its natural range, and after that date its area—at least in Latin America and Asia—could increase. Much of this woodland will be secondary forest, but even so they suggest that in Africa only 16-35% of tropical-forest species will become extinct by 2030, in Asia, 21-24% and, in Latin America, fewer still. Once forest cover does start increasing, the rate of extinction should diminish gradually.
    [F]   This new view of the prospects for biodiversity emerged from a symposium held this week at the Smithsonian Institution in Washington, DC, but the controversy over how bad things really are has been brewing since 2006. That was when Joseph Wright of the Smithsonian Tropical Research Institute in Panama and Helene Muller-Landau of the University of Minnesota first suggested that the damage might not be as grim as some feared. They reasoned that because population growth is slowing in many tropical countries, and people are moving to cities, the pressure to cut down primary rainforest is falling and agriculturally marginal land is being abandoned, allowing trees to grow.
    [G]   There are, however, two criticisms of this analysis. The first questions whether the raw data about forest cover are a good indicator of biodiversity, at least for big animals. William Laurance, a colleague of Dr. Wright’s, pointed out to the symposium that birds and mammals are more vulnerable to alterations in their habitat than are insects and other small animals. His data suggest that even in some of the world’s best-protected primary forests, these species face severe pressures.
    【D6】 → 【D7】 → 【D8】 → 【D9】 → G → 【D10】
【D10】

选项

答案B

解析 本题剩下的选项只有B和C。上一段(即G)位置已固定,提出了对前文观点的反驳,认为森林覆盖面积的大小并不太可以反映生物的多样性,指出大型动物对环境改变的适应能力较差。言下之意,有森林并不一定意味着有很多种生物。B提到Elizabeth Bennett...同意(agreed)上文的观点,她还说到了“空林综合症”的现象,这种现象即为“有森林但没什么大型动物”的情况,可见,她agreed的对象正是G中的观点,故B为本题答案。C主要讲climate change对物种生存的威胁,与G提到alterations in their habitat有一定关联,但C首句的内容与G末尾处未构成语义转折,though在此处体现的逻辑不对,故排除C。
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