碳收支是当下一个重要的议题，也是存在较多争议和不确定性的科学问题。在冰期，陆地生物圈的碳被转移到深海中，已被广泛认识。然而，在冰消期，由海洋释放的CO2通量，及其如何导致各大圈层系统碳库的重新组织和配分，我们知之甚少。
中科院地球环境研究所金章东团队与美国哥伦比亚大学Lamont-Doherty Earth Observatory的Jimin Yu和Wally Broecker、英国剑桥大学Harry Elderfield等著名科学家合作，通过对全球主要大洋底栖有孔虫B/Ca和δ13C组成的系统研究及与陆地记录的对比，定量化了末次冰期以来海洋、陆地和大气碳库之间相互交换作用的变化及其交换通量。
结果表明，由深海释放的CO2在冰消期早期（17.5～14.5kyr）主要存储于大气中，而在冰消期晚期（14～10kyr）很大部分被陆地生物圈生长的植被所吸收利用。这对于认识冰期—间冰期尺度下大气CO2变化的原因以及过去气候变化具有重要的科学意义，并将为全球变暖情形下全球碳收支提供最直接的类比情景。
评审人对该项成果给予了高度的评论，认为是“一个重大的进展”。该研究成果发表在近日出版的Science上，并作为亮点论文推荐。（生物谷Bioon.com）
生物谷推荐原文出处：
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.
