首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
考研
Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emiss
Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emiss
admin
2011-03-14
12
问题
Lead deposits, which accumulated in soil and snow during the 1960’s and 70’s, were primarily the result of leaded gasoline emissions originating in the United States. In the twenty years that the Clean Air Act has mandated unleaded gas use in the United States, the lead accumulation worldwide has decreased significantly.
A study published recently in the journal Nature shows that air-borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic (北极的) snow were declining.
In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasolines and thus enabled scientists to differentiate the lead sources. The dominant lead ratio found in Greenland snow matched that found ingasoline from the United States.
In a study published in the journal Ambio, scientists found that levels in soil in the Northeastern United States had decreased markedly since the introduction of unleaded gasoline.
Many scientists had believed that the lead would stay in soil and snow for a longer period.
The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990. The forest environment processed and redistributed the lead faster than the scientists had expected.
Scientists say both studies demonstrate that certain parts of the ecosystem respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute.
The authors of the Ambio study have found that
选项
A、forests get rid of lead pollution faster than expected.
B、lead accumulations in forests are more difficult to deal with.
C、lead deposits are widely distributed in the forests of the U.S..
D、the upper layers of soil in forests are easily polluted by lead emissions.
答案
A
解析
细节题。根据原文倒数第二段“The forest environment processed and redistributed the lead faster than the scientists had expected.”森林处理和重新分配铅污染的能力超出科学家的预料,同义转述是森林去除、净化铅污染的能力比科学家预计得要强,可知A正确。森林中的铅积累好处理,说明B与文中所述相反。原文没有提及铅沉积在美国的森林中广泛分布,所以C不对;文中没有提到哪层土壤更容易被污染,所以D也不对。
转载请注明原文地址:https://kaotiyun.com/show/hAsa777K
本试题收录于:
MBA联考(英语)题库专业硕士分类
0
MBA联考(英语)
专业硕士
相关试题推荐
某市教育系统评出了十所优秀中学,名单按它们在近三年中毕业生高考录取率的高低排序。专家指出不能把该名单排列的顺序作为评价这些学校教育水平的一个标准。以下哪项如果为真,能作为论据支持专家的结论?()Ⅰ.排列前五名的学校所得到的教育经费
威尔公司和埃克斯公司是两家软件公司,对使用它们的字处理软件的顾客,提供24小时的热线电话服务。既然顾客仅在使用软件有困难时才打电话,并且威尔公司收到的热线电话比埃克斯公司收到的热线电话多四倍,因此,威尔公司的字处理软件一定是比埃克斯公司的字处理软件难用。以
Inthissection,youareaskedtowriteanessaybasedonthefollowingdiagram.Describethediagramandanalyzethepossiblec
Byeducation,Imeantheinfluenceoftheenvironmentupontheindividualtoproduceapermanentchangeinthehabitsofbehavio
Youshouldn’tbeso______—Ididn’tmeananythingbadinwhatIsaid.
Studythefollowingchartscarefullyandwriteanessayinwhichyoushould:1)describethechartbriefly,2)interpre
GimblespeakshighlyofLongakerinthat______.Thebesttitleforthepassagemightbe______.
Americansdon’tliketolosewars.Ofcourse,alotdependsonhowyoudefinejustwhatawaris.Thereareshootingwars—theki
Somehousesaredesignedtobesmart.Othershavesmartdesigns.AnexampleofthesecondtypeofhousewonanAwardofExcellen
Itwaswhenhetookajobinacompany______hebegantolearnEnglish.
随机试题
下列成语故事中,出自《三国演义》的是()。
下列选项中,属于暖肝煎组成药物的是
人群中ApoE可有几种不同的表型
在工程建设各个阶段工程造价控制的主要方法包括()。
随着不确定因素变化百分率取值的不同,()。
已知:某上市公司现有资金10000万元,其中:普通股股本3500万元,长期借款6000万元,留存收益500万元。长期借款年利率为8%,有关投资服务机构的统计资料表明,该上市公司股票的β系数为1.5。目前整个股票市场平均收益率为8%,无风险报酬率为5%。公司
关于旅游投诉处理中涉及的鉴定或检测事项,下列说法不正确的是()。
法律关系是指法律规范调整而形成的社会关系,下列选项中,属于法律关系的是()。
金钱不是万能的,没有钱是万万不能的,发不义之财是绝对不行的。以下除哪些项外,基本表达了上述题干的思想?()Ⅰ.有些事情不是仅有钱就能办成的,比如抗洪抢险的将士冒生命危险坚守堤防,不是为了钱才去干的。Ⅱ.有钱能使鬼推磨。
Whatisthespeaker’smajor?Itis______.
最新回复
(
0
)