首页
登录
职称英语
This passage is adapted from material published in 1993
This passage is adapted from material published in 1993
游客
2024-01-10
63
管理
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 is primarily concerned with discussing the
选项
A、importance of forests for protection the land and atmosphere
B、role of forests in the tropics versus that in the higher latitudes.
C、process of deforestation in the tropics
D、need for forests to ensure the preservation of biodiversity
E、negative effects of recent global climatic changes in forests.
答案
A
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3349436.html
相关试题推荐
(Thispassagewaswrittenpriorto1950)Wenowknowthatwhatcons
ThispassageisadaptedfromTheAmericanRepublic:Constitution,Tendencie
ThispassageisadaptedfromTheAmericanRepublic:Constitution,Tendencie
ThispassageisadaptedfromTheAmericanRepublic:Constitution,Tendencie
ElementsofthePhilosophyofNewton,publishedbyVoltairein1738,wasanearl
Thispassageisadaptedfrommaterialpublishedin2001.FrederickDouglasswas
Thispassageisadaptedfrommaterialpublishedin2001.FrederickDouglasswas
Thispassageisadaptedfrommaterialpublishedin2001.FrederickDouglasswas
Thenewcompositematerialexhibitsanextraordinarydegreeof______,whichenab
Byrecyclingmaterialsandsalvagingunusedsupplies,thehealthcareindustryc
随机试题
Manyafemaleclerk______aboutunequaltreatmentatworkinthiscompany.A、com
关于一节一价制,下列说法正确的有()。A、将每个交易日分成若干节B、在欧美较为普遍C、没有连续不断的竞价D、每一节交易中,一种合约只有一个价格A
Justlikechildren,deeroftencrossBritishroadstogettotheotherside.
Mostpeoplehaterockmusic.【C1】______Iamnotanunreasonableorbiasedper
两个相邻的施工队(组)在保持连续施工的条件下,先后进入第一个施工段进行流水施工的
下列标记不是按钮的是()A.type="submit" B.type="res
6个月小儿体检时发现胸骨左缘2~3肋间闻及Ⅲ级左右连续机器样杂音,向颈部、锁骨下
当房地产需求持续增加,但增长势头逐渐减弱时,房地产市场处在()。A.上升
疮疡溃破,气血不足,久不愈合,可以用( )。A.当归四逆汤 B.犀黄丸 C
我国银行监管领域所依据的主要法律包括()。 A.《银行业监督管理法》
最新回复
(
0
)