Sedimentation dynamics and microbial degradation of marine aggregates: hydrodynamic fundamentals of particulate carbon transport in the ocean

海洋聚集体的沉积动力学和微生物降解：海洋中颗粒碳传输的水动力基础

• 批准号: 276129098
• 负责人: Professor Dr. Hans-Peter Grossart, since 12/2016
• 金额: --
• 依托单位: Department of Computer Science and Electrical Engineering
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/276129098?language=en
• 关键词: Sedimentation; dynamics; microbial; degradation; marine

Marine aggregates build the backbone of biological carbon pump in the ocean by exporting the particulate organic carbon into the deeper water layers via sedimentation.We target at constructing a combined hydrodynamic-microbiological project for characterization of effective vertical transport by marine aggregates with special emphasis on microbial turnover rates within the aggregates. By combining the laboratory experiments with numerical simulations, we first parametrize the sinking velocity of the aggregates as a function of size, porosity, composition and density stratification of the ambient fluid. Next, the mass transfer between the interstitial fluid and the ambient water as well as the microbial turnover rates within the aggregates will be determined as a function of sinking velocity. Based on this, a mathematical model will be developed which mimics reliably the sinking velocity and mass transfer. Such a model will enable us for the first time to provide a realistic estimation of the efficiency of the biological carbon pump. Furthermore, the model delivers valuable inputs and approaches to integrate marine processes into available global climate and oceanic carbon circulation models.

海洋骨料通过沉积将颗粒有机碳输送到更深的水层，从而构建了海洋生物碳泵的支柱。我们的目标是构建一个水动力-微生物相结合的项目，用于表征海洋骨料的有效垂直运输，特别强调骨料内的微生物周转率。通过将实验室实验与数值模拟相结合，我们首先将骨料的下沉速度参数化为周围流体的尺寸、孔隙率、成分和密度分层的函数。接下来，间质液和环境水之间的质量传递以及聚集体内的微生物周转率将被确定为下沉速度的函数。 在此基础上，将开发一个数学模型，可靠地模拟下沉速度和质量传递。 这样的模型将使我们首次能够对生物碳泵的效率进行现实的估计。此外，该模型还提供了宝贵的输入和方法，将海洋过程整合到可用的全球气候和海洋碳循环模型中。