GRE阅读题目解析:水中的死亡区域

　　P21

　　There have long been dead zones—water too low in oxygen to sustain most forms of life—in the Gulf of Mexico, which receives the waters of the Mississippi River. Scientists studied sediment cores from areas where the gulf’s most recent dead zone occurred. The scientists dated the sediment and counted species of foraminifera (marine protozoans) in the sediment; these species thrive in low-oxygen waters. As far back as 1823, the foraminifera thrived especially during Mississippi River flood years (during which nutrients levels increase), suggesting that nutrients in floodwaters can trigger low-oxygen water. The foraminifera in the core samples were most abundant after 1950, when farmers began using some fertilizer, which is rich in nutrients. Researchers believe that increased use of fertilizer leads to more-extreme dead zones.

　　1. Which of the following best describes the function of the highlighted sentence in the context of the passage as a whole?

　　A. It reconciles two opposing theories that were discussed earlier in the passage.

　　B. It suggests what the initial impetus was for the studies mentioned earlier in the passage.

　　C. It undermines a hypothesis that was presented in the preceding sentence.

　　D. It describes a problem with the methodology of the studies discussed in the passage.

　　E. It provides evidence supporting the belief mentioned in the final sentence of the passage.

　　Consider each of the choices separately and select all that apply.

　　2. It can be inferred from the passage that the “researchers” would agree with which of the following statements about the use of fertilizer?

　　A. If farmers near the Mississippi River decreased the amount of fertilizer that they used, the severity of the dead zones could be diminished.

　　B. If farmers near the Mississippi River continue their dependence upon fertilizers, foraminifera population will eventually decline.

　　C. If farmers near the Mississippi River stopped using fertilizers altogether, there would no longer be dead zones.

　　P21

　　1

　　There have long been dead zones — water too low in oxygen to sustain most forms of life — in the Gulf of Mexico, which receives the waters of the Mississippi River.

　　一直以来就存在死亡区域 —— 水中含氧量过低多数生命形式都难以存活 —— 在密西西比河倾注到墨西哥湾的水体中。

　　2

　　Scientists studied sediment cores from areas where the gulf’s most recent dead zone occurred.

　　科学家们研究了来自于墨西哥湾最近出现死区水域的沉淀核心。

　　3

　　The scientists dated the sediment and counted species of foraminifera (marine protozoans) in the sediment; these species thrive in low-oxygen waters.

　　科学家们鉴定了沉淀的年代，并计算出沉淀中的有孔虫(海洋原生动物)物种数量;这些物种能在缺氧水体中茁壮成长。

　　4

　　As far back as 1823, the foraminifera thrived especially during Mississippi River flood years (during which nutrients levels increase), suggesting that nutrients in floodwaters can trigger low-oxygen water.

　　从 1823 年(的记录)开始，特别是密西西比河泛滥的年份(河水携带的养分更多)有孔虫都会暴增，意味着洪水携带的养分可导致水中氧含量变低。

　　5

　　The foraminifera in the core samples were most abundant after 1950, when farmers began using some fertilizer, which is rich in nutrients.

　　沉淀核心样品种的有孔虫自 1950 年后普遍充足，正值农民们开始使用某些富含养分的肥料。

　　6

　　Researchers believe that increased use of fertilizer leads to more-extreme dead zones.

　　研究者们认为，更多地使用肥料导致死区问题加剧。

　　1. Which of the following best describes the function of the highlighted sentence in the context of the passage as a whole?

　　A. It reconciles two opposing theories that were discussed earlier in the passage.

　　B. It suggests what the initial impetus was for the studies mentioned earlier in the passage.

　　C. It undermines a hypothesis that was presented in the preceding sentence.

　　D. It describes a problem with the methodology of the studies discussed in the passage.

　　E. It provides evidence supporting the belief mentioned in the final sentence of the passage.

　　选 E

　　作为证据为最后一句话提供支持。送分题。

　　Consider each of the choices separately and select all that apply.

　　2. It can be inferred from the passage that the “researchers” would agree with which of the following statements about the use of fertilizer?

　　A. If farmers near the Mississippi River decreased the amount of fertilizer that they used, the severity of the dead zones could be diminished.

　　B. If farmers near the Mississippi River continue their dependence upon fertilizers, foraminifera population will eventually decline.

　　C. If farmers near the Mississippi River stopped using fertilizers altogether, there would no longer be dead zones.

　　选 A

　　A

　　正确。根据最后一句：… increased use of fertilizer leads to more-extreme dead zones. A 是这句话的同义转述。

　　B

　　干扰项。从实际情况推测，B 可能是正确的，当 foraminifera 的繁殖超过河水携带的最大养分供给，耗尽了生存资源，数量肯定会 decline 。但这层逻辑无法从文中给出的内容推出，不满足题设要求 inferred from the passage，不选。

　　C

　　未知信息。不但文中没有讨论，而且很可能是错的。文段开头就告诉我们：There have long been dead zones … ;最后一句也说农民使用肥料是 加剧了 more-extreme 这种现象。有理由怀疑即使没有人类活动，墨西哥湾里一样会有 dead zone 。

       以上就是本文的全部内容，更多精彩请随时关注新东方长春学校官网。

相关推荐

长春新东方留学直通车