2. 职称英语
  3. This passage is adapted from material published in 1993

This passage is adapted from material published in 1993

游客2024-01-10  72
问题                         This passage is adapted from material published in 1993
    The recent recognition of a link between increasing rates of deforestation and increasing global climatic warming has focused new attention on the ecological role of forests. Deforestation threatens the continued existence o forests, and their loss would lead to an immediate, irreversible destabilization of the climate because the destructio of forests contributes to increased atmospheric concentrations of such heat-trapping gases as carbon dioxide and therefore to the acceleration of global warming.
    The world is at present accumulating carbon dioxide in the atmosphere from two well-known sources: the combustion of fossil fuels and deforestation. Deforestation results in higher levels of carbon dioxide in the atmosphere because the carbon stored in plants and trees is released when trees decay or are burned. A third sources, the warming-enhanced decay of organic matter in forests and soils, especially in the middle and higher latitudes, is now being recognized as potentially significant. Evidence is accumulating that carbon from this source is beginning to have global effects. Thus, two of the three sources of carbon dioxide in the atmosphere are directly related to the survival and health of forests.
    In the discussion about the importance of forests, however, emphasize has fallen on biodiversity, or numbers of species per unit area, especially in the tropics, where such diversity is particularly high. But forests, it should be emphasized, have a similar role in every latitude. They contain the largest numbers of different kinds of plants and animals of any community on land and might be considered the most highly developed of the terrestrial communities from the standpoint of complexity of structure and diversity of life and life forms. Forests are far more than simple collections of species, however. It is unfortunate that the discussion of biotic or living resources has been focused on biodiversity rather than on the actual ability of the land itself to support life. In order for the complete range of plant and animal life to thrive, the soil must contain essential nutrients in their proper quantities and proportions, and the atmosphere must be composed of the correct molecules in their proper proportions. If the soils were to become infertile and the atmosphere inhospitable, more than mere diversity or numbers of species would be lost, the land would become impoverished and no longer be able to support any life. [br] The passage suggests that the emphasis on a forests biodiversity has had which of the following unfortunate consequences?
选项 A、It has fostered the view that forests have a similar role in every climate.
B、It has fostered the view that deforestation almost invariably speeds erosion
C、It has fostered resistance to preserving any forests but tropical ones.
D、It has led to an increase in the rate at which the land is becoming impoverished
E、It has led to an underestimation of the importance of some forests
答案 E
解析 看到题干的unfortunate会很自然地定位到第三段第五句，于是就找不到答案了。其实第三段的一到五都能传达作者对关注多样性的负面态度，这五句话都是本题的定位范围。根据前三句可知。关注生物多样性会导致人们过分关注热带森林，但是森林在每个纬度上的生物多样性是类似的，所以关注多样性会导致对非热带森林的低估，选项E正确，some forests指的便是非热带的森林。
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