Collaborative research: A Study of Wave-Enhanced Nutrient Uptake by Vegetated Canopies in Shallow Coastal Systems

我们目前对水流对底栖生物系统中化学交换速率的影响的了解主要是基于在静水或单向水流中进行的研究。然而，最近已证明，波浪驱动的振荡流在控制珊瑚礁等生境中的化学交换率方面发挥了重要作用。海草是许多浅水生态系统的重要组成部分，它是一个独特的问题，因为它们很灵活，可以填满很大一部分水深。在这个项目中，来自斯坦福大学和南佛罗里达大学的研究人员将首次系统地研究在一系列不同的波浪条件和树冠密度下，自然树冠内的振荡流诱导的速度结构。他们将详细分析在自然和受控流动条件下，地中海藻树冠内的平均和湍流速度结构，以确定树冠形态参数(例如树冠密度)对流动结构的影响。此外，这将是第一次详细研究在原位振荡流动条件下，整个树冠和树冠内的生物所测得的流动结构与同时测量的养分吸收速率之间的耦合。它们将把流场、光照水平、物理树冠结构和群落组成整合到一个统计相关性类型的预测模型中，以预测单个群落组成部分的养分吸收，最终是整个树冠形成群落的养分吸收。他们的结果也将对受浅海系统小规模水动力影响的其他生物和化学过程产生影响。在更广泛的影响中，一所历史悠久的黑人大学继续向学生伸出援手，这将增加未被充分代表的少数族裔接触海洋学的机会，并增加他们从事学术科学事业的可能性。其他教育外展项目包括制作三个电视节目、公共外展海报和高中物理课程。此外，这项研究将资助一名博士后研究员和两名研究生，他们将在两个实验室进行交叉培训。

Our current state of knowledge on the effects of water flow on chemical exchange rates in benthic systems is primarily based on research conducted in still water or in unidirectional flow. However wave-driven oscillatory flow has recently been shown to play a major role in controlling chemical exchange rates in habitats such as coral reefs. Seagrasses, an important component of many shallow water ecosystems, pose a unique problem because they are flexible and can fill a significant portion of the water depth. In this project, researchers from Stanford University and University of South Florida will conduct the first systematic study of the velocity structure induced by oscillatory flow within natural canopies under a range of different wave conditions and canopy densities. They will conduct a detailed analysis of the mean and turbulent velocity structure within a Thalassia testudinum canopy under natural and controlled flow conditions to determine the effects of canopy morphological parameters (e.g. canopy density) on the flow structure. Additionally, this will be the first study to investigate in detail the coupling of the measured flow structure with simultaneous measurements of nutrient uptake rates by the entire canopy and organisms within the canopy under oscillatory flow conditions in situ. They will integrate flow field, light levels, physical canopy structure and community composition into a statistical-correlation type predictive model for nutrient uptake by individual community components, and ultimately entire canopy-forming communities. Their results will also have implications for other biological and chemical processes affected by small-scale hydrodynamics in shallow coastal systems. Among the broader impacts is continued outreach to students at a Historically Black University that will increase the exposure of under-represented minorities to oceanography and increase the likelihood that they will pursue a career in academic science. Additional educational outreach programs include the production of three television programs, public outreach posters, and a curriculum for high school physics. In addition, the research will fund a post-doctoral fellow and two graduate students who will be cross-trained in the two laboratories.