"CMG Research: Delayed Settling of Marine Snow Through Density Transitions and Consequences for the Ocean Carbon Cycle"

“CMG 研究：通过密度转变延迟海洋雪沉降以及对海洋碳循环的影响”

• 批准号: 1025523
• 负责人: Richard McLaughlin
• 金额: $ 92.11万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1025523&HistoricalAwards=false
• 关键词: CMG; Research; Delayed; Settling; Marine

Funds are provided to improve understanding of the fluid dynamics behind marine aggregate settling, in particular investigating the processes by which marine snow, an aggregate of small particles within a mucous-like matrix, accumulates at density transitions and their implications for prolonged residence times in the surface ocean. This will be accomplished through a combination of careful laboratory fluid dynamics experiments and rigorous mathematical hydrodynamic theory in concert with state-of-the-art biogeochemical laboratory measurements. The consequences of these prolonged residence times will be assessed by biogeochemical measurements of the rates of microbial activity, and conversion of particulate organic carbon to dissolved organic carbon and CO2. A synthesis of the biological and physical components will be achieved by combined experiments that directly measure organic matter transformation during settling through a stratified seawater column, linking the physical and biological timescales under conditions representative of the ocean. The results of this work should inform development of improved models of carbon sequestration in the deep ocean, an essential process in the global carbon cycle. The project will contribute to the scientific workforce by supporting an early career faculty member, as well as the continued training of a post-doctoral associate, two graduate students, and four undergraduate students.

提供资金以提高对海洋骨料沉降背后的流体动力学的理解，特别是研究海洋雪（黏液样基质内的小颗粒集合体）在密度转变时积累的过程及其对在海洋表面停留时间延长的影响。这将通过仔细的实验室流体动力学实验和严格的数学流体动力学理论与最先进的生物地球化学实验室测量相结合来完成。这些延长的停留时间的后果将通过微生物活动率的生物地球化学测量和微粒有机碳向溶解有机碳和二氧化碳的转化来评估。生物和物理成分的综合将通过联合实验来实现，这些实验直接测量通过分层海水柱沉降过程中的有机物转化，将具有代表性的海洋条件下的物理和生物时间尺度联系起来。这项工作的结果应该为开发改进的深海碳封存模型提供信息，这是全球碳循环的一个重要过程。该项目将通过支持一名早期职业教师，以及继续培训一名博士后、两名研究生和四名本科生，为科研队伍做出贡献。