首页
登录
职称英语
Scientists have long believed one way to stop the Earth’ s atmosphere from w
Scientists have long believed one way to stop the Earth’ s atmosphere from w
游客
2023-09-03
53
管理
问题
Scientists have long believed one way to stop the Earth’ s atmosphere from warming is by planting more trees. The idea is that more trees will take in or absorb stone of the carbon dioxide in the atmosphere. Carbon dioxide is a gas released by cars, factories and other human activities. The gas traps heat in the Earth’ s atmosphere, which warms tile planet. However, two new studies have found that trees may not be as helpful in reducing carbon dioxide as had been thought.
The first study was done at Duke University in Durham, North Carolina. Researchers pumped extra carbon dioxide into a test area where pine trees were growing. The trees grew thirty -four percent faster during the first three years. However, in time, the trees slowed to about their normal growth rate. The scientists say this is because trees need other nutrients, such as nitrogen.
In the second study, researchers from Duke and Bowdoin College in Brunswick, Maine examined the soil around trees. They discovered that as the leaves broke down into the soil, all the carbon was not trapped in the soil. Much of it was released into the atmosphere as carbon dioxide.
The findings of the two studies were published last month in Nature magazine. They suggest there is limited value in planting trees to reduce the carbon dioxide pollution in the atmosphere.
Forest planting has been a part of negotiations on a world agreement to reduce greenhouse gases that scientists believe cause global warming. The United States, Canada, Japan and some other industrial countries have supported the idea. But this new research suggests the idea is not as effective as environmental activists had thought. Scientist Ram Oren of Duke University led the study on tree growth. He says that earlier estimates on the ability of forests to absorb carbon dioxide were overly hopeful. Some scientists not involved in the studies say the research provides some of the first evidence on how trees react to carbon dioxide. Other scientists say the research disputes a belief among some coal and power companies. The companies say that rising levels of carbon dioxide in the atmosphere will not create harmful global warming. Instead, they say it will increase forests and other plants. [br] What happened to the leaves falling from the trees in the second study?
选项
A、They broke down and the main parts turned into oxygen.
B、They broke down and the carbon content had mainly turned into carbon dioxide.
C、They broke down and the carbon content was mainly absorbed in the soil.
D、They absorbed more carbon dioxide.
答案
B
解析
关键语句:“They discovered that as the leaves broke down into the soil,all the carbon was not trapped in the soil.Much of it was released into the atmosphere as carbon dioxide.”而A,C,D均错误。
转载请注明原文地址:https://tihaiku.com/zcyy/2981969.html
相关试题推荐
[originaltext]Americanscientistsaredevelopingmapsthatcanidentifyare
[originaltext]Americanscientistsaredevelopingmapsthatcanidentifyare
ScientistshavelongbelievedonewaytostoptheEarth’satmospherefromw
ScientistshavelongbelievedonewaytostoptheEarth’satmospherefromw
ScientistshavelongbelievedonewaytostoptheEarth’satmospherefromw
ManyleadingscientistsdownthroughtheyearsfromGalileotoEinsteinhave
ManyleadingscientistsdownthroughtheyearsfromGalileotoEinsteinhave
Scientistshavecomeupwithatheoryforwhytimeflieswhenyonarehaving
Scientistshavecomeupwithatheoryforwhytimeflieswhenyonarehaving
Scientistshavecomeupwithatheoryforwhytimeflieswhenyonarehaving
随机试题
HereisastoryI’dliketoshare:Abutcherwatchingoverhisshopisr
DefinitionsofObesityA)Howdoesonedefinewhena
简述实施乡村振兴战略的目标任务。
20世纪40年代社会学家()提出了“要比较中西差别,建立真正适合中国的社会行政
谁当经理更合适? 某电子电器工业公司是一个由十几家小厂组成的专业公司,公司行政
在VisualFoxPro中,下列各项的数据类型所占字符的字节数相等的是A.日期
发现游客食物中毒,导游人员应()。A.稳定患者情绪 B.让食物中毒者多喝水以加
下图为某国工业化、城市化进程比较图。读图完成21~22题。 关于
1.低压熔断器更换应注意哪些内容?() A应查明原因并处理后方
企业参照自身的历史水平或者同行业的先进水平制定生产标准,这种制定生产标准的方法是
最新回复
(
0
)