碳收支是當(dāng)下一個(gè)重要的議題,，也是存在較多爭議和不確定性的科學(xué)問題。在冰期,，陸地生物圈的碳被轉(zhuǎn)移到深海中,，已被廣泛認(rèn)識(shí)。然而,，在冰消期,，由海洋釋放的CO2通量，及其如何導(dǎo)致各大圈層系統(tǒng)碳庫的重新組織和配分,，我們知之甚少,。
中科院地球環(huán)境研究所金章東團(tuán)隊(duì)與美國哥倫比亞大學(xué)Lamont-Doherty Earth Observatory的Jimin Yu和Wally Broecker、英國劍橋大學(xué)Harry Elderfield等著名科學(xué)家合作,，通過對(duì)全球主要大洋底棲有孔蟲B/Ca和δ13C組成的系統(tǒng)研究及與陸地記錄的對(duì)比,，定量化了末次冰期以來海洋、陸地和大氣碳庫之間相互交換作用的變化及其交換通量,。
結(jié)果表明,，由深海釋放的CO2在冰消期早期（17.5～14.5kyr）主要存儲(chǔ)于大氣中，而在冰消期晚期（14～10kyr）很大部分被陸地生物圈生長的植被所吸收利用,。這對(duì)于認(rèn)識(shí)冰期—間冰期尺度下大氣CO2變化的原因以及過去氣候變化具有重要的科學(xué)意義,，并將為全球變暖情形下全球碳收支提供最直接的類比情景。
評(píng)審人對(duì)該項(xiàng)成果給予了高度的評(píng)論,，認(rèn)為是“一個(gè)重大的進(jìn)展”,。該研究成果發(fā)表在近日出版的Science上，并作為亮點(diǎn)論文推薦,。（生物谷Bioon.com）
生物谷推薦原文出處：
Science DOI: 10.1126/science.1193221
Loss of Carbon from the Deep Sea Since the Last Glacial Maximum
Jimin Yu1,*, Wally S. Broecker1, Harry Elderfield2, Zhangdong Jin3, Jerry McManus1 and Fei Zhang3
Abstract
Deep-ocean carbonate ion concentrations ([CO32–]) and carbon isotopic ratios (δ13C) place important constraints on past redistributions of carbon in the ocean-land-atmosphere system and hence provide clues to the causes of atmospheric CO2 concentration changes. However, existing deep-sea [CO32–] reconstructions conflict with one another, complicating paleoceanographic interpretations. Here, we present deep-sea [CO32–] for five cores from the three major oceans quantified using benthic foraminiferal boron/calcium ratios since the last glacial period. Combined benthic δ13C and [CO32–] results indicate that deep-sea-released CO2 during the early deglacial period (17.5 to 14.5 thousand years ago) was preferentially stored in the atmosphere, whereas during the late deglacial period (14 to 10 thousand years ago), besides contributing to the contemporary atmospheric CO2 rise, a substantial portion of CO2 released from oceans was absorbed by the terrestrial biosphere.
