Mass Exchange between Flexible Submerged Canopies and Adjacent Open Water

海草草甸在沿海地区具有重要的生态和经济影响。它们提供的营养循环价值每年3.8万亿美元。此外，海草床为许多具有重要经济意义的海洋物种提供了生境，并影响着沿海地区沉积物和碳的命运。海草草甸内重要的生物地球化学过程以及海草对周围环境的影响受草甸和周围开阔水域之间的动量和质量交换的调节。先前的一些研究已经描述了与刚性冠层相关的质量和动量传输。然而，我们对柔性檐篷的运输只有有限的了解。本计画将以现有的刚性檐篷理论为基础，发展弹性檐篷在单向流与波浪条件下的物质输运模式。智力优势：该项目将开发在单向流和波浪条件下柔性淹没檐篷中湍流交换的新模型。这项工作将有助于我们对生物流相互作用的基本理解。此外，这项工作有助于涉及气象学科的多孔层附近的流动和运输的广泛主题（陆地树冠），多孔介质（潜流交换）和生物海洋学（海藻林、海草、珊瑚生态）对社会的更广泛影响和潜在惠益：通过提供柔性沉水植被内部和周围通量的物理模型，该项目将有助于建立一个更好的框架，以研究和衡量这些树冠内发生的吸收、定居和补充过程。此外，通量模型将使草甸几何形状（长度，高度，干密度）如何影响草甸更定量的考虑？的影响，这反过来又会导致更好地预测生态系统的反应，营养负荷的变化或海草分布的变化。此外，该项目每年将为一名研究生和至少一名本科生提供培训。该项目还将形成一个新的本科生实验室活动的基础上，将纳入主要研究者？目前的大三课程。最后，研究人员将利用这项工作作为与麻省理工学院Seagrant Eelgrass恢复项目继续互动的平台。

Seagrass meadows have a significant ecologic and economic impact in coastal regions. The nutrient cycling they provide is valued at 3.8 trillion dollars per year. In addition seagrass beds provide habitat for many economically important marine species and influence the fate of sediment and carbon in the coastal-zone. The important biogeochemical processes within a seagrass meadow, as well as the impact of seagrass on the surrounding environment, are regulated by the exchanges of momentum and mass between the meadow and surrounding open water. Several previous studies have described the mass and momentum transport associated with rigid canopies. However, we have only a limited understanding of transport in flexible canopies. This project will build on existing theories for rigid canopies to develop mass transport models for flexible canopies under both unidirectional flow and wave conditions. Intellectual Merit: The project will develop new models for turbulent exchange in flexible submerged canopies under both unidirectional flow and wave conditions. This work will contribute to our basic understanding of bio-flow interaction. In addition, the work contributes to the broad topic of flow and transport near porous layers that touches disciplines in meteorology (terrestrial canopies), porous media (hyporheic exchange), and biological oceanography (kelp forest, seagrass, coral ecology)Broader Impacts and Potential Benefits to Society: By providing physical models for flux in and around flexible, submerged vegetation, this project will contribute to a better framework for studying and measuring the uptake, settling, and recruitment processes that occur within these canopies. In addition, the flux models will enable a more quantitative consideration of how meadow geometry (length, height, stem density) influences a meadow?s impact on the surrounding ecosystem, which in turn will lead to better predictions of ecosystem response to changes in nutrient load or changes in seagrass distribution. In addition, the project will provide training for one graduate and at least one undergraduate student per year. The project will also form the basis for a new undergraduate laboratory activity, to be incorporated into the Principal Investigator?s current Junior year course. Finally, the investigator will use this work as a platform for continued interaction with the MIT Seagrant Eelgrass Restoration Project.