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托福阅读事实信息题合集之tpo3-3

信息来源:网络  发布时间:2015-05-29

  托福阅读事实信息题是阅读考试中比较常见的一种题型,tpo则是托福阅读 备考 最权威的材料,所以托福小编综合二者,为大家集中整理了tpo阅读中考察的事实信息题及其对应的解析,供大家参考使用。本文带来的是tpo3-3的事实信息题,一起来看看吧。

  TPO3-3 The Long-Term Stability of Ecosystems

  Paragraph 3:

  At one time, ecologists believed that species diversity made ecosystems stable. They believed that the greater the diversity the more stable the ecosystem. Support for this idea came from the observation that long-lasting climax communities usually have more complex food webs and more species diversity than pioneer communities. Ecologists concluded that the apparent stability of climax ecosystems depended on their complexity. To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather to pests.

  4. According to paragraph 3, ecologists once believed that which of the following illustrated the most stable ecosystems?

  ○Pioneer communities

  ○Climax communities

  ○Single-crop farmlands

  ○Successional plant communities

  解析: 以ecologists做关键词定位至本段第一句,说生态学家认为生态系统中物种越多越稳定。接着在举例子的时候作者举到了climax communities,说明生态学家认为climax communities最稳定,答案B

  【3】生态学家们一度认为物种的多样性使生态系统稳定,生态系统物种越多样则生态系统越稳定。通过观察得出的结论支持了这个观点,长期持久的顶极群落通常要比先锋群落具备更为复杂的食物网和更多的物种。生态学家家们得出的结论是:顶点生态系统的稳定性明显取决于他们的复杂化程度。举个极端的例子,在单一作物的农田中,一年的恶劣天气或单一害虫的入侵就可以摧毁所有作物。与此相反,在一个复杂的顶极群落里,如温带森林,他们便可以抵御来自气候和害虫的干扰和入侵。

  Paragraph 4:

  The question of ecosystem stability is complicated, however. The first problem is that ecologists do not all agree what “stability” means. Stability can be defined as simply lack of change. In that case, the climax community would be considered the most stable, since, by definition, it changes the least over time. Alternatively, stability can be defined as the speed with which an ecosystem returns to a particular form following a major disturbance, such as a fire. This kind of stability is also called resilience. In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state.

  5. According to paragraph 4, why is the question of ecosystem stability complicated?

  ○The reasons for ecosystem change are not always clear.

  ○Ecologists often confuse the word “stability” with the word “resilience.”

  ○The exact meaning of the word “stability” is debated by ecologists.

  ○There are many different answers to ecological questions.

  解析:question of ecosystem stability为关键词定位至本段头两句,说生态学家对于什么是生态系统的稳定性依然存在争议,C是原文的忠实改写

  【4】不管怎样,生态系统稳定性的问题非常复杂。首先,不是所有的生态学家都赞同“稳定”的含义。稳定性可以简单地定义为缺乏变化。如果是这样的话,顶极群落将被视为最稳定的,因为根据定义,他们随着时间推移而变化得最少。另外,稳定性也可以界定为生态系统在经历了严重破坏之后回复原貌的速度,比如火灾。这种稳定性也被称作弹性。在这种情况下,顶极群落将是最脆弱和最不稳定的,因为他们可能需要数百年时间才能恢复到顶点状态。

  6. According to paragraph 4, which of the following is true of climax communities?

  ○They are more resilient than pioneer communities.

  ○They can be considered both the most and the least stable communities.

  ○They are stable because they recover quickly after major disturbances.

  ○They are the most resilient communities because they change the least over time.

  解析:关于climax communities原文有两个地方提到。因为生态学家对什么是稳定这个问题存在两个观点,以不变这种观点看,climax是最稳定的,以快速恢复这种观点看,climax是最不稳定的,所以climax既稳定也不稳定,B明确说到两个方面,其它选项都只说到一个方面.

  【4】不管怎样,生态系统稳定性的问题非常复杂。首先,不是所有的生态学家都赞同“稳定”的含义。稳定性可以简单地定义为缺乏变化。如果是这样的话,顶极群落将被视为最稳定的,因为根据定义,他们随着时间推移而变化得最少。另外,稳定性也可以界定为生态系统在经历了严重破坏之后回复原貌的速度,比如火灾。这种稳定性也被称作弹性。在这种情况下,顶极群落将是最脆弱和最不稳定的,因为他们可能需要数百年时间才能恢复到顶点状态。

  以上就是托福阅读tpo3-3中的事实信息题及其解析,大家可以在备考的时候参考复习,希望能够帮助大家的考前准备。最后前程百利祝大家都能取得理想的托福考试 成绩。

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