Dissolved Organic Carbon (DOC) in the ocean represents the largest reductive carbon reservoir in the global marine system, and even minor fluctuations can significantly impact global carbon cycling patterns. The Southern Ocean serves as a potent carbon sink, and the seas surrounding Antarctica and its continent exhibit rapid responses to global climate change, characterized by dynamic and highly heterogeneous environmental conditions. Physical and chemical factors such as sea ice, light exposure, ocean currents, water masses, and nutrient distribution, as well as microbial influences, continuously modulate the distribution patterns of DOC concentration and properties in the surface waters of the Antarctic region. Current research on DOC in the Antarctic region primarily focuses on coastal areas such as the Amundsen Sea, the Prydz Bay, the Ross Sea, and the Antarctic Peninsula, with a notable lack of comprehensive, systematic studies on the overall distribution patterns of surface water DOC across the Antarctic scale, as well as the physical, chemical, and biological driving mechanisms. This project aims to utilize spectral, mass spectrometric, and stable isotope methods to systematically investigate the distribution patterns of DOC quantity and characteristics in the surface waters of the Antarctic region. Additionally, it will employ 16S rRNA gene and Metagenomic sequencing, combined with multivariate statistical analysis, machine learning models, process simulations, and spatiotemporal analysis, to explore the synergistic effects and driving mechanisms of environmental factors and microbial activities on DOC distribution. This study is of significant importance for a comprehensive understanding of the processes and mechanisms governing the dissolved carbon cycle in south polar marine environments.

Surface waters of Antarctica; Carbon Cycle; Dissolved Organic Carbon; Molecular Composition; Biogeochemistry