| 摘要: |
| 底栖有孔虫碳同位素（δ13C）是研究地质历史时期碳循环和大洋深部环流的重要指标。通过汇编42条过去130 ka以来底栖有孔虫的δ13C记录，建立全球大洋深部以及不同水团包括北大西洋深层水（NADW）和太平洋深层水（PDW）的δ13Cstack （数据存储格式为.xlsx），以及海洋同位素阶段（marine isotope stage，MIS）5-1期大西洋和印度-太平洋δ13C经向剖面，探索130 ka以来大洋无机碳δ13C的演变特征及其与碳循环和大洋深部经向环流的关联。结果表明全球碳同位素在冰期较低，间冰期较高，且大西洋振幅高于太平洋。末次盛冰期海水表层温度及海平面都比MIS 4期略低，但MIS 4期δ13C更偏负，其可能原因是北大西洋通风减弱增加了深海对大气CO2的固存，导致大气CO2浓度的降低。但该结论并未考虑南大洋其他生物化学过程，未来研究将重点探讨南大洋其他生物化学过程与碳循环的相互作用，进一步深化对这一复杂系统的理解。 |
| 关键词: 碳循环 海洋环流 北大西洋深层水 末次盛冰期 |
| DOI：10.7515/JEE243014 |
| CSTR： |
| 分类号: |
| 基金项目:崂山实验室科技创新项目（LSKJ202203300） |
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| Benthic foraminifera δ13C reveals changes in ocean circulation over 130 ka |
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YANG Mengfei1, SUN Yachen2, 3, MA Xiaolin2*
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1. State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an 710069, China
2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
3. University of Chinese Academy of Sciences, Beijing 100049, China
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| Abstract: |
| Benthic foraminifera stable carbon isotope (δ13C) is an important proxy for the study of carbon cycle and deep ocean circulation in geological history. In this study, we established global δ13C stacks for the deep ocean and different water masses, including the North Atlantic deep water and Pacific deep water and Atlantic and Indo-Pacific δ13C meridional profiles during Marine Isotope Stage (MIS) 5-1 by compiling 42 δ13C records of benthic foraminifera over the past 130 ka, to explore the variations of oceanic inorganic carbon δ13C and its correlation with the carbon cycle and meridional circulation in the deep ocean since 130 ka. The results indicate that the global δ13C is low (high) in the glacial (interglacial) periods and the amplitude of δ13C in the Atlantic Ocean is higher than Pacific Ocean. In addition, the sea surface temperature and sea level were low and δ13C was enriched during the Last Glacial Maximum (LGM). By contrast, an opposite situation occurred during the MIS 4. The possible reason for this phenomenon is that the weakened ventilation of the North Atlantic increased the sequestration of atmospheric CO2 in the deep sea, leading to less atmospheric occurring in MIS 4. However, this conclusion does not consider other biochemical processes in the Southern Ocean, thus we will focus on the interaction of other biochemical processes in the Southern Ocean with the carbon cycle in order to further deepen the understanding of this complex system. |
| Key words: carbon cycle ocean circulation North Atlantic deep water Last Glacial Maximum |
