Collaborative Research: Zooplankton mediation of particle formation in the Sargasso Sea

合作研究：浮游动物介导马尾藻海颗粒形成

• 批准号: 2023621
• 负责人: Susanne Neuer
• 金额: $ 61.91万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023621&HistoricalAwards=false
• 关键词: Collaborative; Research; Zooplankton; mediation; particle

The purpose of this collaborative project is to advance understanding of the role of marine planktonic animals (or zooplankton) in the biological pump, or transport of carbon from surface to deeper ocean waters. This movement of carbon from surface to deep ocean water can ultimately affect carbon dioxide in the atmosphere, with implications for global climate. Many marine zooplankton, including species of copepods and krill, play a direct role in the biological pump both because they are abundant and because they can migrate from surface waters at night, where they feed, to depths of more than 500 m at night. At the same time, some organisms called flux feeders will remain at depth and do not migrate. Instead, they rely on particles produced by other zooplankton feeding in surface waters. In this project, the investigators are focusing on populations of flux feeders in the deeper ocean waters of the Sargasso Sea. They are leveraging an ongoing long-term research program, conducting field collections using specialized nets and particle traps, as well lab experiments, as a way to understand how these organisms modify the particles around them. This project is supporting a postdoctoral scientist and providing research experiences for undergraduates at two institutions. An education specialist is creating lesson plans for an award-winning Ask-A-Biologist website, designed for public and K-12 audiences. Images of zooplankton will be disseminated to the public and scientific community via EcoTaxa (a web platform devoted to plankton biodiversity, with images and taxonomic annotation) and physical samples will be archived as part of a teaching library. The oceanic biological carbon pump refers to the export of dissolved and particulate organic carbon to the deep ocean, and it is a significant driver of atmospheric carbon uptake by the oceans. Evidence from long-term research carried out at the Bermuda Atlantic Time-series Study (BATS) site suggests that the spectrum of particles collected by gel-traps below the euphotic zone changes drastically below 150 m, which is attributed to resident populations of zooplankton that feed on vertically migrating zooplankton as well as sinking particles. The goals of this study are to investigate the role of different zooplankton taxa on both particle aggregate formation and in particle transformation, and to compare and characterize the particles generated by the zooplankton communities with those collected by particle traps. The investigators are combining field collections with experiments onboard ship and in environmental chambers. They are collecting samples over two years, with three cruises a year to capture distinct seasons. They are assessing high-resolution vertical distribution of zooplankton in the upper 600 m using Multiple Opening-Closing Net and Environmental Sensing System (MOCNESS) tows during day- and night-time, to distinguish diel vertical migrators from resident populations and to quantify contributions to particulate organic carbon flux via fecal pellet production. On each cruise, sinking particles are being collected using gel trap tubes attached to the particle traps deployed monthly at BATS. In addition, roller tank experiments are determining how individual zooplankton mediate aggregate formation. Particle types and fecal pellets are being characterized using image analysis and DNA-based analysis of microbial communities. Finally, ongoing data collection from the long-term BATS program is providing invaluable environmental context and will ensure results from this study contribute to ongoing community efforts to observe and predict the fate of carbon in our global system.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

这一合作项目的目的是促进对海洋浮游动物（或浮游动物）在生物泵或将碳从海洋表面沃茨输送到更深处的过程中的作用的了解。碳从表层到深海的这种运动最终会影响大气中的二氧化碳，从而对全球气候产生影响。许多海洋浮游动物，包括桡足类和磷虾，在生物泵中发挥直接作用，因为它们数量丰富，而且它们可以在夜间从它们觅食的表层沃茨迁移到500米以上的深度。与此同时，一些被称为通量饲养者的生物将留在深处，而不是迁移。相反，它们依赖于其他浮游动物在表面沃茨中进食产生的颗粒。在这个项目中，研究人员的重点是在马尾藻海的更深的海洋沃茨的通量饲养人口。他们正在利用一个正在进行的长期研究计划，使用专门的网和颗粒捕集器进行实地收集，以及实验室实验，以了解这些生物如何改变周围的颗粒。该项目正在支持一名博士后科学家，并为两个机构的本科生提供研究经验。一位教育专家正在为一个获奖的Ask-A-Biologist网站创建课程计划，该网站是为公众和K-12观众设计的。浮游动物的图像将通过EcoTaxa（一个专门研究浮游生物多样性的网络平台，附有图像和分类注释）向公众和科学界传播，实物样本将作为教学图书馆的一部分存档。海洋生物碳泵是指将溶解的和颗粒状的有机碳输出到深海，它是海洋吸收大气碳的重要驱动力。在百慕大大西洋时间序列研究站进行的长期研究的证据表明，凝胶捕集器在真光层以下收集的颗粒光谱在150米以下发生急剧变化，这是由于浮游动物的常驻种群以垂直迁移的浮游动物和下沉颗粒为食。本研究的目标是调查不同的浮游动物类群的颗粒聚集体的形成和颗粒转化的作用，并比较和表征所产生的浮游动物群落与颗粒捕集器收集的颗粒。研究人员正在将实地收集与船上和环境室中的实验相结合。他们在两年的时间里收集样本，每年进行三次巡航，以捕捉不同的季节。他们正在利用多张开合网和环境传感系统（MOCNESS）在白天和夜间拖曳，评估浮游动物在600米以上的高分辨率垂直分布，以区分昼夜垂直迁移者和居民种群，并量化粪便颗粒对颗粒有机碳通量的贡献。在每次巡航中，正在使用连接到每月在BATS部署的颗粒捕集器上的凝胶捕集管收集沉降颗粒。此外，滚筒水槽实验正在确定个体浮游动物如何介导聚集体的形成。正在使用图像分析和基于DNA的微生物群落分析来表征颗粒类型和粪便颗粒。最后，从长期BATS计划正在进行的数据收集提供了宝贵的环境背景，并将确保本研究的结果有助于持续的社区努力，观察和预测碳在我们的全球系统中的命运。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。