Collaborative Research: Orientation of elongate diatoms as a strategy for light harvesting

合作研究：细长硅藻的方向作为光收集的策略

• 批准号: 1657332
• 负责人: James Sullivan
• 金额: $ 28.91万
• 依托单位: Florida Atlantic University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2021-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1657332&HistoricalAwards=false
• 关键词: Collaborative; Research; Orientation; elongate; diatoms

Phytoplankton have an intimate connection to the hydrodynamic environment in which they live.Previous studies have examined the role that turbulence and shear play in nutrient uptake, patch/layer formation, and predator-prey encounters, but the role of phytoplankton orientation to increase light capture (and ultimately primary production) has been largely overlooked. Compelling evidence of persistent horizontal orientation of chain-forming diatoms, obtained from novel in situ holographic imaging, has led to a hypothesis that in regions of strong stratification, shear flows will lead to systematic horizontal orientation of elongate phytoplankton forms that maximizes their cross-sectional area (and light capture) in the ambient downwelling light field. It has also been suggested that variations in phytoplankton size and shape are fundamental traits conferring selective competitive advantages in certain hydrodynamic environments, thus modifying/mediating community composition. The interdisciplinary research of this project crosses three scientific disciplines (biology, optics and fluid dynamics) and will advance our understanding of the function of diverse forms of phytoplankton, their interactions with fluid flows, and the resultant impacts on the optics of the environment. The project will support a number of undergraduate and graduate students, and post-doctoral researchers. This project combines analysis of previously collected field data with laboratory experiments and modeling. For the field data analysis, phytoplankton orientation is quantified from in situ holographic images of the undisturbed water column along with concurrent high resolution measurements of critical physical (turbulence/shear/stratification) and optical parameters collected from a ship-based holographic bio-physics profiler. In the laboratory, the orientation response of different phytoplankton species and morphologies is evaluated in custom built shear tanks under controlled laminar and turbulent conditions to confirm that elongate forms can orient in certain hydrodynamic environments to maximize light capture. In addition, controlled growth/physiology experiments in various shear tank treatments will explore the effects of orientation on growth, photosynthetic parameters and productivity. Lastly, the project results will be incorporated into a global analysis of observed and modeled physical, bio-optical and ecologically-relevant parameters, to quantify the relevance of this phenomenon to primary production and the carbon cycle.

浮游植物与其生活的水动力环境有着密切的联系。之前的研究已经研究了湍流和剪切力在养分吸收、斑块/层形成和捕食者与猎物相遇中所起的作用，但浮游植物定向对增加光捕获（以及最终初级生产）的作用在很大程度上被忽视了。从新颖的原位全息成像中获得的链形成硅藻持续水平方向的令人信服的证据导致了一个假设，即在强烈分层的区域中，剪切流将导致细长浮游植物形式的系统水平方向，从而最大化其在环境下流光场中的横截面积（和光捕获）。也有人提出，浮游植物大小和形状的变化是在某些水动力环境中赋予选择性竞争优势的基本特征，从而改变/调节群落组成。该项目的跨学科研究跨越三个科学学科（生物学、光学和流体动力学），将增进我们对不同形式浮游植物的功能、它们与流体流动的相互作用以及由此对环境光学产生的影响的理解。该项目将支持一批本科生、研究生以及博士后研究人员。该项目将对先前收集的现场数据的分析与实验室实验和建模相结合。对于现场数据分析，浮游植物的方向是根据未受干扰的水柱的原位全息图像以及从船基全息生物物理剖面仪收集的关键物理（湍流/剪切/分层）和光学参数的并发高分辨率测量来量化的。在实验室中，在受控层流和湍流条件下，在定制的剪切池中评估不同浮游植物种类和形态的定向响应，以确认细长形式可以在某些水动力环境中定向，以最大限度地捕获光。此外，各种剪切罐处理中的受控生长/生理学实验将探讨方向对生长、光合参数和生产力的影响。最后，该项目的结果将被纳入对观测和建模的物理、生物光学和生态相关参数的全球分析中，以量化这种现象与初级生产和碳循环的相关性。

项目成果

Enhanced Light Absorption by Horizontally Oriented Diatom Colonies

水平定向硅藻菌落增强光吸收

• DOI: 10.3389/fmars.2020.00494
• 发表时间: 2020
• 期刊: Frontiers in Marine Science
• 影响因子: 3.7
• 作者: McFarland, Malcolm;Nayak, Aditya R.;Stockley, Nicole;Twardowski, Michael;Sullivan, James
• 通讯作者: Sullivan, James

High-Resolution Sampling of a Broad Marine Life Size Spectrum Reveals Differing Size- and Composition-Based Associations With Physical Oceanographic Structure

• DOI: 10.3389/fmars.2020.542701
• 发表时间: 2020-12-22
• 期刊: FRONTIERS IN MARINE SCIENCE
• 影响因子: 3.7
• 作者: Greer, Adam T.;Lehrter, John C.;Penta, Bradley
• 通讯作者: Penta, Bradley

Editorial: Small Scale Spatial and Temporal Patterns in Particles, Plankton, and Other Organisms

社论：颗粒、浮游生物和其他生物的小规模时空模式

• DOI: 10.3389/fmars.2021.669530
• 发表时间: 2021
• 期刊: Frontiers in Marine Science
• 影响因子: 3.7
• 作者: Nayak, Aditya R.;Jiang, Houshuo;Byron, Margaret L.;Sullivan, James M.;McFarland, Malcolm N.;Murphy, David W.
• 通讯作者: Murphy, David W.

Automated plankton classification from holographic imagery with deep convolutional neural networks

• DOI: 10.1002/lom3.10402
• 发表时间: 2020-12-03
• 期刊: LIMNOLOGY AND OCEANOGRAPHY-METHODS
• 影响因子: 2.7
• 作者: Guo, Buyu;Nyman, Lisa;Hong, Jiarong
• 通讯作者: Hong, Jiarong

“Breaking” news for the ocean's carbon budget

有关海洋碳预算的“重大新闻”

• DOI: 10.1126/science.aba7109
• 发表时间: 2020
• 期刊: Science
• 影响因子: 56.9
• 作者: Nayak, Aditya R.;Twardowski, Michael S.
• 通讯作者: Twardowski, Michael S.