南大洋典型海域微型生物类群结构/微型生物碳泵(MCP)储碳效率对SAM/ENSO的响应

南大洋是全球海洋最大碳汇，其储碳能力可能正在降低。探究南大洋微型生物类群结构变化/微型生物碳泵（MCP）储碳效率对大气和海洋过程等外部强迫响应——凸显重要和紧迫。科学界已获得南半球环状模（SAM）异常对南极局地影响的重要认识，且与ENSO关系密切。本项目研究利用微型生物细胞膜脂（GDGTs）建立几种可引起DOC碳库组成/MCP效率改变的特定古菌的生物量和类群结构变化与GDGTs生物标志物指示的气候要素(海温-TEX86L和氧化还原-%Cren)的定量关系，重点关注奇古菌（氨氧化古菌）及其与SAM/ENSO互动响应史；结合现代水柱（POM/GDGTs）与海底沉积物中GDGTs/类脂生物标志物地球化学对MCP储碳效应的表征和动态规律，从全新的视角揭示南大洋特定微型生物类群结构变化/MCP储碳效率（增强/削弱）与SAM/ENSO的内在联系，这对于认识全球气候变化的海洋调控机制具有重要的科学意义。

The southern ocean, the largest carbon sink in the world's oceans, may be losing its capacity to store carbon. To explore the carbon storage efficiency of the southern ocean microbiological group structure /microbiological carbon pump (MCP) in response to external forcings such as atmospheric and oceanic processes highlighting the importance and urgency. The scientific community has obtained an important understanding of the southern hemisphere annular module (SAM) anomaly on the local impact of Antarctica, and is closely related to ENSO. Based on the importance of microbiome composition to the fate of dissolved organic carbon (DOC) and the carbon storage efficiency of MCP, this study used microbial cell membrane lipid to determine the causes of carbon library/MCP efficiency change of several specific archaea: spring archaea, wide archaea, archaea, focus on the odd archaea (ammonia oxidation archaea) characteristics and changes of energy metabolism; To reconstruct quantitative relationship between the changes of biomass and group structure and the climatic factors indicated by the GDGTs/lipids biomarkers and the history of the interaction with SAM/ENSO; It is of great significance for us to understand the marine regulatory mechanism of global climate change by combining the characterization of the carbon storage effect of MCP (MCP dynamic change law and the strength of carbon storage efficiency) and its internal relationship with SAM/ENSO in modern water column (POC/GDGTs) and the biogeochemical characteristics of GDGTs/lipids biomarkers in seabed sediments.