Collaborative Research: Assessing the relative importance of small vs large particles as sources of nutrition to abyssal communities

合作研究：评估小颗粒与大颗粒作为深海群落营养来源的相对重要性

• 批准号: 1829612
• 负责人: Jeffrey Drazen
• 金额: $ 107.09万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829612&HistoricalAwards=false
• 关键词: Collaborative; Research; Assessing; relative; importance

The abyssal plains of the oceans cover roughly half of the earth's surface, host enormous reservoirs of biodiversity and mineral resources, and play important roles in nutrient recycling and carbon sequestration. The most important process controlling the structure and function of these ecosystems is the quantity and quality of food (mostly sinking organic particles) that reaches the deep-sea floor. However, we do not fully understand the processes provisioning this vast ecosystem. We propose to evaluate the relative importance of small and larger "marine snow" particles that sink to deep-sea benthic communities by using the stable isotope signature of amino acids within various food sources and trace their consumption by fauna on the seafloor. This project compares ecosystems from the productive waters off California with the nutrient poor central Pacific, north of Hawaii. This project provides novel insights into how surface ocean processes are coupled to food-webs at the deep ocean seafloor and how changes in food sources potentially impact deep-sea communities. This project also provides excellent training opportunities for graduate students, a postdoctoral researcher, and undergraduates at UH and USC, particularly underrepresented minorities who pursue majors in the geosciences. The project will sponsor an annual G6-12 teacher workshop to inform Hawaii educators about the deep sea and broadly disseminate knowledge to the community. All results are communicated broadly to inform the public as concerns regarding abyssal ecosystems are rising due to interests in deep-sea mining. The most important process controlling the structure and function of abyssal ecosystems is the quantity and quality of organic material that ultimately reaches the deep-sea floor. Despite the strong relationship between euphotic zone export flux and benthic ecology, studies of abyssal ecosystems have observed a deficit between food supply and benthic community demand. Additional work is therefore needed, particularly with regards to understanding the sources of nutrition to the deep-sea benthos. Recent evidence suggests that small particles may be significant contributors to carbon export, increasing in relative importance with depth in the mesopelagic and reaching the abyssal seafloor. This project is to evaluate the relative importance of small and larger "marine snow" particles to deep-sea benthic communities using a combination of particle flux measurements and state of the art compound specific stable isotope analysis of amino acids (AA-CSIA) at two abyssal locations that contrast in overlying productivity, seasonality, and export magnitude. Time series measurements at these locations (Sta. M off California and Sta. Aloha off Hawaii) provide a rich context for the work. In the mesopelagic central North Pacific larger particles (53 um) can be resolved from microbially reworked, smaller (0.7-53 um) particles using AA-CSIA. This project is characterizing the isotopic compositions of key individual compounds in a continuum of particle sizes ( 1.0 um suspended particles to large sinking particles 53 um) collected using in situ filtration near the seafloor and bottom-moored sediment traps, thereby defining source-specific isotopic signatures that can be traced into benthic fauna and sediments (that are collected by ROVs and epibenthic sleds). This research to understand pelagic-benthic coupling from particles to megafauna using isotopic measurements at the compound-level will yield novel insights into the importance of small microbially reworked particles to deep-sea benthic food webs. This will more precisely couple surface ocean processes to food-webs at the deep ocean seafloor with implications for understanding climate change effects and the efficiency of energy transfer to higher trophic levels. Furthermore, isotopic measurements can also be used to further parameterize ecosystem models by quantifying trophic position across size classes and thus estimate predator-prey mass ratios in relation to variation in body size spectra, functional type, and ultimately to carbon flux and remineralization. Finally, the results will help refine interpretations of deep-sea paleorecords of past nitrogen dynamics by calibrating potential changes in organic matter isotope values between the surface and seafloor archives.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.

海洋的深海平原覆盖了大约一半的地球表面，拥有巨大的生物多样性和矿产资源库，并在养分循环和碳固存方面发挥着重要作用。控制这些生态系统的结构和功能的最重要过程是到达深海海底的食物（主要是下沉的有机颗粒）的数量和质量。然而，我们并不完全了解这个庞大生态系统的供应过程。我们建议通过使用各种食物来源中氨基酸的稳定同位素特征，并追踪海底动物的消费情况，评估沉入深海底栖生物群落的小型和大型“海洋雪”颗粒的相对重要性。该项目比较了加州附近的多产沃茨与夏威夷北部营养贫乏的太平洋中部的生态系统。该项目提供了关于表层海洋过程如何与深海海底的食物网耦合以及食物来源的变化如何潜在地影响深海群落的新见解。该项目还为研究生，博士后研究员和UH和南加州大学的本科生提供了极好的培训机会，特别是那些追求地球科学专业的代表性不足的少数民族。该项目将每年主办一次G6-12教师讲习班，向夏威夷教育工作者介绍深海，并向社区广泛传播知识。由于对深海采矿的兴趣，人们对深海生态系统的关切日益增加，所有结果都得到广泛传播，以告知公众。控制深海生态系统结构和功能的最重要过程是最终到达深海海底的有机物质的数量和质量。尽管真光层输出通量与底栖生态之间存在密切关系，但对深海生态系统的研究发现，食物供应与底栖群落需求之间存在缺口。因此，需要开展更多的工作，特别是了解深海底栖生物的营养来源。最近的证据表明，小颗粒可能是碳输出的重要因素，在中层和深海海底，随着深度的增加，其相对重要性也在增加。该项目的目的是在两个在重叠生产力、季节性和输出量方面形成对比的深海地点，利用粒子通量测量和最先进的化合物特定氨基酸稳定同位素分析相结合的方法，评估大小不同的“海洋雪”粒子对深海底栖生物群落的相对重要性。这些位置的时间序列测量（Sta.我在加州和斯塔。阿罗哈关闭夏威夷）提供了一个丰富的背景下的工作。在中层中的北太平洋较大的颗粒（53微米）可以从微生物改造，较小的颗粒（0.7-53微米）使用AA-CSIA解决。该项目正在对使用海底附近的现场过滤和海底系泊沉积物捕集器收集的一系列粒径（1.0微米悬浮颗粒至53微米大沉降颗粒）中的关键单个化合物的同位素组成进行定性，从而确定可追溯到海底动物和沉积物（由遥控潜水器和海底雪橇收集）的特定来源同位素特征。这项研究旨在利用化合物一级的同位素测量来了解从颗粒到巨型动物的水层-底栖耦合，这将使人们对微生物改造的小颗粒对深海底栖食物网的重要性有新的认识。这将更精确地将表层海洋过程与深海海底的食物网联系起来，对理解气候变化的影响和向更高营养水平转移能量的效率具有影响。此外，同位素测量也可以用来进一步parameterized生态系统模型，通过量化的营养位置跨大小类，从而估计捕食者-猎物质量比的变化，在身体大小谱，功能类型，并最终碳通量和生物矿化。最后，研究结果将有助于通过校准表面和海底档案之间有机物同位素值的潜在变化来完善对过去氮动力学的深海古记录的解释。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

项目成果

Environmental, evolutionary, and ecological drivers of slow growth in deep-sea demersal teleosts

深海底层硬骨鱼缓慢生长的环境、进化和生态驱动因素

• DOI: 10.3354/meps13591
• 发表时间: 2021
• 期刊: Marine Ecology Progress Series
• 影响因子: 2.5
• 作者: Black, JA;Neuheimer, AB;Horn, PL;Tracey, DM;Drazen, JC
• 通讯作者: Drazen, JC

Deep zooplankton rely on small particles when particle fluxes are low

当颗粒通量较低时，深层浮游动物依赖小颗粒

• DOI: 10.1002/lol2.10163
• 发表时间: 2020
• 期刊: Limnology and oceanography letters
• 影响因子: 7.8
• 作者: Romero-Romero, Sonia;Ka’apu-Lyons, Cassie A.;Umhau, Blaire P.;Benitez-Nelson, Claudia R.;Hannides, Cecelia C.;Close, Hilary G.;Drazen, Jeffrey C.;Popp, Brian N.
• 通讯作者: Popp, Brian N.