"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”

基本信息

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

项目摘要

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.

提供了资金来提高对海洋聚集沉降背后的流体动力学的了解，特别是研究了海洋积雪，海洋雪，粘液样基质中的小颗粒的聚集体，在密度过渡时积聚，及其对在地表海中长期居住时间的影响。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结合在一起来实现这一目标，并与最先进的生物地球化学实验室测量一起完成。这些延长停留时间的后果将通过生物地球化学测量对微生物活性速率以及颗粒有机碳转化为溶解有机碳和CO2的后果。通过合并的实验将实现生物和物理成分的合成，这些实验可以直接测量通过分层海水柱沉降过程中有机物转化，并在代表海洋的条件下将物理和生物学时间尺度联系起来。这项工作的结果应为深海中改进的碳固存模型的发展提供信息，这是全球碳循环中的重要过程。该项目将通过支持早期职业教职员工，并继续培训博士后同学，两名研究生和四名本科生，从而为科学劳动力做出贡献。