字神帝國英語天地

✿ 今日主題：深埋海底的微生物反映了陸地起源
Microbes Deep under Seafloor Reflect Ancient Land Origins

✿ 托福聽力最好的課外教材：60-Second Science
堅持每天聽一定會進步的哦!!

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✿ 聽不懂地方，再來參考中英文稿：

Microbial organisms live in you, on you, in soil,in clouds and below the ocean floor. That last batch of single-celled critters is particularly hard to study. Not only are the samples difficult to obtain, but they can easily be contaminated with all that other microbial life once we dig them up.
微生物存在於我們的體內、體表、土壤裡、雲層以及海底。尤其是，最後一批單細胞生物很難進行研究，因為這些單細胞生物的樣本不僅很難獲得，而且，一旦將這些樣本挖掘出來，它們很容易被其他微生物污染。

So researchers had to take special precautions when they investigated microbial life in a coal bed deep below the seafloor near Japan. This material was once dry land, but got submerged some 20 million years ago.
所以，研究者們在日本附近的海底煤層研究微生物時，必須採取特殊的預防措施。這個煤層曾經是干燥的陸地，但是在大約在2千萬年以前，沉入了海底。

The research team drilled nearly 2,500 meters below the seafloor and brought up samples. They carefully avoided contamination and evaluated only the inner portions of the samples, which were protected by the outer parts.
研究團隊在海底鑽探約2500米深，獲取了很多樣本。他們仔細操作避免污染，只在被外層保護的內部進行取材評估。

Analysis found life tenaciously holding on well under the ocean. A gram of rich garden soil can hold a billion bacteria—at 2,500 meters below the seafloor a gram of sediment might be home to just a single microbe. And those deeply buried organisms are quite different from microbes to be found just under the seafloor.
分析發現，生命在海底也頑強生存著。一克花園裡肥沃的土壤，可以存活十億個細菌——但在2500米深的海底，一克淤泥，只有一個微生物。並且那些被深埋地下的微生物和僅在海底之下的微生區別甚多。

In that deep layer, the microbes are most closely related to bacterial groups that thrive in forest soils on land. The scientists thus suggest that the deeply buried undersea microbes might be descendants of ones that survived when their terrestrial habitat became flooded. Again, that was 20 million years ago. The finding is in the journal Science.
在海底深層的微生物和在陸地森林土壤裡旺盛繁殖的微生物幾乎有著密切的聯繫。因此，科學家們認為，這些深埋海底的微生物可能是那些棲息地被洪水淹沒的陸生生物倖存者的後代，同樣，洪水發生在2000千萬年以前。該研究成果發表在《科學》雜誌上。

In a commentary in the same issue, Julie Huber of the Marine Biological Laboratory at Woods Hole says the fact that there's 「a massive buried biosphere」 has global importance 「with sub-seafloor microbes playing a crucial role in carbon sequestration…and Earth's evolution, and likely encompassing staggering metabolic and genetic diversity.」 She adds, 「We still have a long way to go in uncovering and understanding microbial life deep beneath the seafloor.」
在同期的一篇評論文章中，來自伍茲霍爾的海洋生物實驗室的朱莉‧胡貝爾(Julie Huber)稱大量被掩埋的生物圈對全球有著重要的作用。「海底下的微生物對碳封存...以及地球進化有著重要的作用，甚至可能對驚人的代謝能力以及遺傳 的多樣性也意義非凡。」她還補充說道：「我們離揭示和理解海底微生物的奧秘還有很長的距離。」