小小海藻能解决全球变暖问题?

Ocean plants buried in sediment can help reveal Earth’s temperature thousands of years ago. That’s according to Daniel Sigman of Princeton, winner of a 2009 MacArthur “genius grant”. Dr. Sigman has been trying to piece together how efficiently tiny ocean plants – algae – were using nitrogen about 20,000 years ago.

土壤沉积物中掩埋的海洋植物能帮助人们解开地球上千年前的气温之谜。2009年麦克·阿瑟基金会天才奖得主、来自普林斯顿大学的丹尼尔·西格曼如是说。西格曼博士致力于研究两万年前微型海洋植物海藻是如何高效利用氮元素的。

Daniel Sigman: Algae require nitrogen to grow, and their bodies, in turn, fuel the rest of the ocean food web.

丹尼尔·西格曼：海藻生长过程中需要氮，而海藻本身为海洋食物链中的其他生物提供养分。

Sigman explained that by measuring algae’s use of nitrogen, he can gauge how much these ancient organisms used another important element – carbon dioxide, or CO2. All earthly plants use CO2 for photosynthesis. CO2 is also a major greenhouse gas in Earth’s atmosphere. Excess CO2 warms the Earth.

西格曼告诉记者，通过研究海藻如何利用氮元素，他将能了解这些原始海洋生物对地球上另一重要分子二氧化碳的利用情况。地球上所有植物都通过二氧化碳进行光合作用。二氧化碳也是地球大气中的主要温室气体，一旦过量将造成全球变暖。

Daniel Sigman: The ocean is responsible for lowering carbon dioxide in the atmosphere as much as the forests on land are.

丹尼尔·西格曼：海洋在减少大气中二氧化碳的含量上所起的作用和陆地上的森林相同。

That’s because algae take CO2 out of surface water. And, when the algae die, Sigman said, they sink.

这是因为海藻吸收水面上的二氧化碳。西格曼说，死亡的海藻会沉入海底。

Daniel Sigman: And transfer it into the deap sea, where it cannot escape back to the atmosphere.

丹尼尔·西格曼：然后将吸入的气体一起带到深海，这样二氧化碳就无法逸回大气。

Thus cooling the planet. Dr. Sigman is currently working to determine the role the ocean played in the global cooling that caused the last ice age. His early research indicates that algae in polar oceans might have played a role.

于是地球变冷了。西格曼博士目前致力于研究海洋在全球变冷及其造成的最近一次冰期中起到了什么作用。其早期研究表明，极地海藻可能在其中发挥了作用。