400-year-old plants from the Little Ice Age were brought back to life, which could help us understand how the Earth will deal with climate change.

Moss(蘚類植物) found buried beneath the Teardrop glacier(冰川) on Ellesmere Island in Canada has been brought back to life. Findings suggest that these plants could help repopulate regions exposed by melting ice caps. Plants that were buried beneath thick ice in Canada more than 400 years ago and were thought to have frozen to death have been brought back to life by Canadian scientists.

Samples of the moss plant, covered by the glacier during the Little Ice Age of 1550 to 1850 AD, were replanted in a lab at the University of Alberta and grew new stems(莖). Researchers now think these findings can give indication as to how regions can recover as the ice covering them melts.

Biologist Dr. Catherine La Farge and her team at the University of Alberta were exploring the region around the Teardrop glacier on Ellesmere Island. Ice on Ellesmere Island region has been melting at around four meters each year for the past nine years. This means that many areas of land that were previously covered by ice have since been exposed. Many ecosystems that were thought to have been destroyed during the Little Ice Age between 1550 and 1850 AD can now be studied, including many species that have never been studied before.

While examining an exposed area of land, La Farge and her team discovered a small area of moss called Aulacomnium turgidum. It is a type of bryophyte(苔蘚類植物) plant that mainly grows across Canada, the US and the Highlands of Scotland.

Dr La Farge noticed that the moss had small patches of green stems, suggesting it is either growing again or can be encouraged to repopulate. Dr La Farge told the BBC, “When we looked at the samples in detail and brought them to the lab, I could see some of the stems actually had new growth of green branches, suggesting that these plants are growing again, and that blew my mind. When we think of thick areas of ice covering the landscape, we’ve always thought that plants have to come from refugia(瀕絕生物保護(hù)區(qū)), never considering that land plants come from underneath a glacier. It’s a whole world of what’s coming out from underneath the glacier that really needs to be studied. The ice is disappearing pretty fast. We really have not examined all the biological systems that exist in the world; we don’t know it all.”

Dr La Farge took samples of the moss and, using carbon-dating techniques, discovered that the plants date back to the Little Ice Age. Dr La Farge’s team took the samples, planted them in dishes full of nutrient-rich potting soil and fed them with water.

The samples were from four separate species including Aulacomnium turgidum, Distichium capillaceum, Encalypta procera and Syntrichia ruralis. The moss plants found by Dr La Farge are types of bryophytes. Bryophytes can survive long winters and regrow when the weather gets warmer.

However, Dr La Farge was surprised that the plants buried under ice have survived into the twenty-first century. Her findings appear in proceedings(論文集)of the National Academy of Sciences.

1.Dr La Farge’s research is of great importance to ________.

A. knowing what the plants during the Little Ice Age were like

B. understanding how ecosystems recover from glaciers.

C. regrowing many species that have been destroyed before.

D. figuring out the effects of melting ice caps on moss.

2.The underlined part “blew my mind” in Paragraph 6 can best be replaced by “________”.

A. surprised me                   B. greatly frightened me

C. put my doubt out of my mind    D. was exactly what I had in my mind

3.According to the passage, Aulacomnium turgidum ________.

A. lives better in small groups              

B. is very active in hot weather

C. is strong enough to survive coldness

D. is chosen from Canadian refugia

4.Which of the following would be the best title for the passage?

A. Bryophyte ecology is greatly affected by climate change.

B. 400-year-old moss’s survival is a mystery to solve.

C. Moss in ancient times was discovered in Canada.

D. 400-year-old plants were brought back to life.

 

【答案】

 

1.B

2.A

3.C

4.D

【解析】

試題分析:文章介紹了生物學(xué)家凱瑟琳La Farge博士和她的團(tuán)隊(duì)發(fā)現(xiàn)400年前冰封在冰川里的苔蘚類植物,在帶回實(shí)驗(yàn)室后放置在營(yíng)養(yǎng)豐富的土壤中,澆水之后又再次生長(zhǎng)。研究表明即使冰封四百年的植物在適宜條件下還會(huì)復(fù)活。

1.推理題:根據(jù)第二段中“Findings suggest that these plants could help repopulate regions exposed by melting ice caps. ”研究表明這些植物可以重新覆蓋冰帽融化地區(qū)。由此可知當(dāng)?shù)氐纳鷳B(tài)系統(tǒng)可從冰川中恢復(fù)過(guò)來(lái)。故選B。

2.推理題:根據(jù)第六段中“I could see some of the stems actually had new growth of green branches, suggesting that these plants are growing again, and that blew my mind.”我可以看到一些綠色的莖有新的增長(zhǎng),表明這些植物可以再次增長(zhǎng),這出乎我的意料。劃線部分意思是“出乎意料”,只有A選項(xiàng)符合語(yǔ)意。故選A。

3.細(xì)節(jié)題:根據(jù)第八段中“Bryophytes can survive long winters and regrow when the weather gets warmer.”苔蘚植物可以在漫長(zhǎng)的冬季存活和當(dāng)天氣變暖時(shí)再生。 Aulacomnium turgidum是苔蘚類植物中一種,因此也可在寒冷中存活。故選C。

4.推理題:根據(jù)文章內(nèi)容可知冰封400年的植物也可以在適合溫度中再次復(fù)活。故選D。

考點(diǎn):考查科學(xué)研究類閱讀   

 

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