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: 2023372
• 负责人: Leocadio Blanco-Bercial
• 金额: $ 40.72万
• 依托单位: Bermuda Institute of Ocean Sciences (BIOS), Inc.
• 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 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023372&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增进对海洋浮游动物(或浮游动物)在生物泵中的作用的了解，即从表层向深海输送碳。碳从表层到深海的这种移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，既是因为它们数量丰富，也是因为它们可以在夜间从它们觅食的表层水域迁移到500多米深的地方。与此同时，一些被称为通量喂食者的生物将留在深海，不会迁徙。相反，它们依赖于其他在地表水中觅食的浮游动物产生的颗粒。在这个项目中，研究人员将重点放在马尾藻海更深的海洋水域中的通量喂食者种群上。他们正在利用一项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野外采集，以及实验室实验，以此来了解这些生物如何改变他们周围的颗粒。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-生物学家网站制作教案，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(一个致力于浮游生物多样性的网络平台，带有图像和分类注释)向公众和科学界传播，物理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有机碳和颗粒有机碳输出到深海，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(BATS)现场进行的长期研究的证据表明，在150米以下，由凝胶陷阱收集的颗粒光谱发生了剧烈变化，这归因于以垂直迁移的浮游动物为食的常驻浮游动物种群以及下沉的颗粒。本研究的目的是调查不同浮游动物类群在颗粒聚集形成和颗粒转化中的作用，并比较和表征浮游动物群落产生的颗粒和颗粒捕捉器收集的颗粒。研究人员正在将现场收集与船上和环境舱中的实验相结合。他们在两年的时间里收集样本，每年三次巡航来捕捉不同的季节。他们正在利用多张开闭网和环境传感系统(MOCNESS)拖网评估600米以上浮游动物的高分辨率垂直分布，以区分垂直迁徙的生物和常驻种群，并量化粪便颗粒生产对颗粒有机碳通量的贡献。在每一次巡航中，下沉的颗粒都是通过连接在BATS每月部署的颗粒捕集器上的凝胶捕集管收集的。此外，滚筒水槽实验正在确定单个浮游动物如何调节聚集体的形成。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，来自长期BATS计划的持续数据收集将提供宝贵的环境背景，并将确保这项研究的结果有助于社区正在进行的努力，以观察和预测碳在我们全球系统中的命运。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。