晚第四纪太平洋深层水对南海深部碳循环的影响

深海探索的新发现证明，深海碳循环在特定时期可以通过上层海洋对大气CO2浓度变化产生影响，是“全球变化”中碳循环的关键过程，也是以往研究忽视的重要环节。本项研究借助“南海深海过程演变”重大研究计划的学术平台，计划采用近几年国际古海洋学新发展的底栖有孔虫B/Ca比值替代性指标，通过对赤道西太平洋（MD01-2386）和南海北部（MD05-2904）柱状样开展底栖有孔虫B/Ca比值测试分析，建立晚第四纪太平洋与南海深层水[CO32-]记录，结合底栖有孔虫属种组合和稳定氧碳同位素测试结果，并与南大洋、北太平洋深层水的古海洋记录比较，来探讨冰期旋回中西太平洋深层海水碳酸盐化学的变化及太平洋深层水对南海深部碳循环的影响，进一步认识晚第四纪南海深水古环境变化，为理解大洋深部洋流和碳循环等全球变化的机制做出贡献。

New discovery of deep-sea exploration has been confirmed that the deep-sea carbon cycle had ever exerted a profound influence on the atmospheric CO2 content through the upper ocean in some specified periods, indicating that the deep-sea carbon cycle is one of the key processes in the global carbon cycle and also a key aspect overlooked before. Relying on the academic platform of the large research project “South China Sea deep process evolution”, this study will apply the newly developed paleoceanographic proxy, boron/calcium (B/Ca) ratio of benthic foraminifera, to reconstruct the deepwater carbonate ion concentration ([CO32-]) in the late Quaternary cores of the western equatorial Pacific (MD01-2386) and the South China Sea (MD05-2904). Through the comprehensive analysis on the deepwater paleoceanographic records (including [CO32-], benthic foraminiferal 13C and faunal indicators) in both cores, this study aims to monitor the changes of deep water carbonate chemistry in the western Pacific and further investigate its influence on the carbon cycle of the SCS deep water. This study will provide new knowledge on the paleoceanographic changes of the SCS deepwater during the late Quaternary, and helps to understand the mechanisms of the global deep circulation and marine carbon cycle.