The response and feedback of ocean carbon sequestration to climate changes is a international hot topic and requires large spatial/temporal scale, collaborative and multi-disciplinary research. In the first conference of GRC Ocean biogeochemistry, scientists focus on three biologically-driven ocean carbon pumps (Biological Pump, BP; Microbial Carbon Pump, MCP; Carbonate Counter Pump, CCP) and their environmental and climate consequences. As a sister meeting in China, we organized the session to show the efforts and progress of ocean carbon sequestration of Chinese scientists. The microbial ecological processes of phytoplankton, bacteria, archaea and viruses and interactions between them were highlighted in the session. Use coral reefs in the South China Sea as an example, the presenters and the participants come to an agreement that interdisciplinary collaborations are needed to ensure a comprehensive understanding of the interactions between microbes and their geochemical environment and the consequences of microbial processing of carbon on outgassing of CO₂ and carbon sequestration. The session also have presentations focusing on paleo-environmental reconstruction for carbon sinks as well as their paleo-ecological effects in ancient oceans with time spanning from the 1.8~0.8 Ga Proterozoic to the 2.5 Ma Quaternary. These talks provide specific geological cases for the oceanic carbon sink research and convey the emerging geological view of paleooceanic carbon sinks to the research community of modern ocean carbon sinks. As a summary, the discussion in this session of biological pump, microbial carbon pump and carbonate counter pump shows the latest research progress and future development trend in this field.