职称英语考试

试题来源：2015年职称英语考试理工类阅读判断习题

    Lead Pollution

    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 (区分) the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States.

    In a study published in the journal Ambio(人类环境杂志), scientists found that lead 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 (生态系统) respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute.

1.The study published in the journal Nature indicates that

A.the US is the major source of lead pollution in arctic snow.

B.the Clean Air Act has not produced the desired results.

C.lead will stay in soil and snow longer than expected.

D.lead deposits in arctic snow are on the increase.

2.Lead accumulation worldwide decreased significantly after the use of unleaded gas in the US

A.was discouraged.

B.was prohibited by law.

C.was enforced by law.

D.was introduced.

3.How did scientists discover the source of lead pollution in Greenland

A.By analyzing the data published in journals like Nature and Ambio.

B.By comparing the chemical compositions of leaded gasoline used in various countries.

C.By observing the lead accumulations in different parts of the arctic area.

D.By studying the chemical elements of soil and snow in Northeastern America.

4.The authors of the Ambio study have found that

A.forests get rid of lead pollution faster than expected.

B.lead deposits are widely distributed in the forests of the US.

C.lead accumulations in forests are more difficult to deal with.

D.the upper layers of soil in forests are easily polluted by lead emissions.

试题出处：http://www.examtiku.com/shiti/6917827392.html
网考网参考答案：A、C、B、A
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大数据分析：根据网考网与考试题库的统计分析，该试题：
1%的考友选择了A选项
69%的考友选择了B选项
18%的考友选择了C选项
12%的考友选择了D选项
考友解析与评论：
 · 大家看教材，书上原话
 · 这个答案靠谱吗？
 · 题目都看不懂，整个就是乱蒙。