Question

    The bristlecone pine is the longest-living thing on the earth. These trees, with their strangely-shaped, wind-beaten limbs(枝干), can live up to 5000 years. But experts worry that a warming climate in some areas may threaten its future.

Researchers say warmer weather is permitting a similar kind of tree, the limber pine, to take over good growing places from the ancient bristlecone. They say the tree is being crowded out of mountainous areas where it grows.

“The bristlecone pine is the oldest individually growing organism,” researchers say. They grow in high mountain forests in eastern California, Nevada and Utah. In those mountains, the trees face high winds and extreme temperatures, which leave them with twisted limbs and shapes. “Even in such tough conditions,” Brian Smithers, a researcher at the University of California, said, “the limber pine is taking all the good spots.”

The limber pine is the bristlecone’s distant relative and competitor. It can also live a long time-up to 2000 years. And it is usually found at lower altitudes, where temperatures are warmer. However, according to a three-year study which centered on trees that have started growing in the last 50 years in California’s White Mountains, most of the trees growing at higher altitudes were limber pines.

Scientists compared the competing species to two old men in a very slow race up a mountainside. This race between such slow-growing trees takes thousands of years. They say climate change is causing the competition.

Smithers said the bristlecone pines are not in danger of disappearing. But he assumes they could be crowded out of some places where they have grown for thousands of years.

The researchers say the findings show how climate change can affect the two kinds of trees. The information, they say, can help scientists understand more complex forests.

1.What’s the function of Paragraph 1?

A.To introduce a topic. B.To summarize the whole passage.

C.To describe the appearance of a tree. D.To praise the hard work of the experts.

2.What does the underlined sentence in Paragraph 2 mean?

A.There will be older trees sent out of those mountains.

B.There will be more places covered with bristlecone pines.

C.There will be better limber pines replacing the ancient ones.

D.There will be fewer bristlecone pines growing in those areas.

3.According to the passage,the reason why limber pines can grow at higher altitudes is_________.

A.the high winds

B.the changing climate

C.the difficult conditions

D.the extreme temperatures

4.What is the researchers’ attitude towards the future of the bristlecone pine?

A.Positive. B.Negative. C.Concerned. D.Enthusiastic.

Answer

1.A

2.D

3.B

4.C

【解析】

这是一篇说明文。文章主要讲述了科学家的一项研究发现：气候变暖使得柔松逐渐抢占了狐尾松的生长地。

1.

推理判断题。通读全文可知，文章主要介绍了狐尾松面临的艰难处境，文章第一段内容but句提出了本文的中心话题“But experts worry that a warming climate in some areas may threaten its future.(但是专家担心一些地区的气候变暖可能会威胁到它的未来。)”，因此可推知，第一段的主要功能是引出本文话题。故选A项。

2.

句义猜测题。根据第二段第1句内容“Researchers say warmer weather is permitting a similar kind of tree, the limber pine, to take over good growing places from the ancient bristlecone.”可知，研究人员说，温暖的天气使得一种类似的树——柔松——取代了古狐尾松的优良生长环境。因此可推知，划线句“the tree is being crowded out of mountainous areas where it grows”应是在讲述这种情况下造成的结果，即：可生长的山区被柔松占据，使得狐尾松生长区域减少，最终导致狐尾松数量减少。选项D“There will be fewer bristlecone pines growing in those areas.( 在那些地区将会有更少的狐尾松生长。)”符合分析。故选D项。

3.

细节理解题。根据文章第二段第1句内容“warmer weather is permitting a similar kind of tree, the limber pine, to take over good growing places from the ancient bristlecone.( 温暖的天气使得一种类似的树——柔松——取代了古狐尾松的优良生长环境。)”以及第四段第3句内容“And it is usually found at lower altitudes, where temperatures are warmer. ( 它通常生长在海拔较低的地方，那里的温度较高。)”可知，气候变暖使得柔松能够在海拔更高的地区生长。故选B项。

4.

推理判断题。根据文章第一段第2句内容“But experts worry that a warming climate in some areas may threaten its future.”可知，专家担心一些地区的气候变暖可能会威胁到它的未来。故选C项。