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OFFICIAL40 What can be inferred from paragraph 4 about a region with a high level of diversity of animal species?

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Latitude and Biodiversity
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When we look at the way in which biodiversity (biological diversity) is distributed over the land surface of the planet, we find that it is far from even. The tropics contain many more species overall than an equivalent area at the higher latitudes. This seems to be true for many different groups of animals and plants.

Why is it that higher latitudes have lower diversities than the tropics? Perhaps it is simply a matter of land area. The tropics contain a larger surface area of land than higher latitudes - a fact that is not always evident when we examine commonly used projections of Earth’s curved surface, since this tends to exaggerate the areas of land in the higher latitudes - and some biogeographers regard the differences in diversity as a reflection of this effect. But an analysis of the data by biologist Klaus Rohde does not support this explanation. Although area may contribute to biodiversity, it is certainly not the whole story; otherwise, large landmasses would always be richer in species.

Productivity seems to be involved instead, though perhaps its influence is indirect. Where conditions are most suitable for plant growth - that is, where temperatures are relatively high and uniform and where there is an ample supply of water - one usually finds large masses of vegetation. This leads to a complex structure in the layers of plant material In a tropical rain forest, for example, a very large quantity of plant material builds up above the surface of the ground. There is also a large mass of material, developed below ground as root tissues, but this is less apparent. Careful analysis of the above ground material reveals that it is arranged in a series of layers, the precise number of layers varying with age and the nature of the forest. The arrangement of the biological mass ("biomass") of the vegetation into layered forms is termed its “structure” (as opposed to its “composition”, which refers to the species of organisms forming the community). Structure is essentially the architecture of vegetation, and as in the case of tropical forests, it can be extremely complicated. In a mature floodplain tropical forest in the Amazon River basin, the canopy (the uppermost layers of a forest, formed by the crowns of trees) takes on a stratified structure. There are three clear peaks in leaf cover at heights of approximately 3, 6, and 30 meters above the ground; and the very highest layer, at 50 meters, corresponds to the very tall trees that stand free of the main canopy and form an open layer of their own. So, such a forest contains essentially four layers of canopy. Forests in temperate lands often have just two canopy layers, so they have much less complex architecture.

Structure has a strong influence on the animal life inhabiting a site. It forms the spatial environment within which an animal feeds, moves around shelters, lives, and breeds. It even affects the climate on a very local level (the "microclimate") by influencing light intensity, humidity, and both the range and extremes of temperature. An area of grassland vegetation with very simple structure, for example, has a very different microclimate at the ground level from that experienced in the upper canopy. Wind speeds are lower, temperatures are lower during the day (but warmer at night), and the relative humidity is much greater near the ground. The complexity of the microclimate is closely related to the complexity of structure in vegetation, and generally speaking, the more complex the structure of vegetation, the more species of animal are able to make a living there. The high plant biomass of the tropics leads to a greater spatial complexity in the environment, and this leads to a higher potential for diversity in the living things that can occupy a region. The climates of the higher latitudes are generally less favorable for the accumulation of large quantities of biomass; hence, the structure of vegetation is simpler and the animal diversity is consequently lower.

11.What can be inferred from paragraph 4 about a region with a high level of diversity of animal species?

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【题目翻译】从第4段可以推断出一个动物物种高度多样的地区是什么? A:它还具有很高的植物物种多样性。 B:微气候比较少 C:与植物物种多样性高的地区相比,它的结构不那么复杂。 D:它产生了一种类似于高纬度地区的生物量。 【判定题型】:根据题干中出现的关键词“imply”/“infer”/“suggest”等其他表示推断的词,判定本题为推理题。 【关键词定位】根据关键词a high level of diversity of animal species定位至其后面的第七句话The high plant biomass of the tropics leads to a greater spatial complexity in the environment, and this leads to a higher potential for diversity in the living things that can occupy a region.热带地区庞大的生物量导致了环境的更大的空间复杂度,也就使得住在这个区域的生物的多样性可能更高。高纬度地区的气候条件一般不利于大量生物的集聚,因此,植被结构更简单些,动物的多样性也相应较低。 【逻辑分析】可知它也同样拥有大量的植物物种多样性。 【选项分析】 A.符合原文,正确。 B.未提到到微气候,故错误。 C.植被结构更简单些,动物的多样性也相应较低。所以植物物种多样性高,动物物种多样性也高。故错误。 D文章:高纬度地区的气候条件一般不利于大量生物的集聚。故错误。

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