Collaborative Research: Transforming Carbon in the Deep Sea

合作研究：深海碳转化

• 批准号: 1851368
• 负责人: Alexander Bochdansky
• 金额: $ 36.48万
• 依托单位: Old Dominion University Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1851368&HistoricalAwards=false
• 关键词: Collaborative; Research; Transforming; Carbon; Deep

Through understanding the biological pump (the ocean's biologically driven sequestration of carbon from the atmosphere to the ocean interior and seafloor sediments), scientists know that the world's oceans absorb more carbon dioxide than it returns to the atmosphere. While much is known about the biological processes largely responsible for the transfer of carbon into the deep sea, very little is known about the microbial decay and subsequent remineralization processes that occur when the carbon reaches the deep sea. Using newly-designed deep-sea incubators deployed off the east coast of the United States, researchers will explore the microbial communities and remineralization processes that transform carbon in the deep sea. The incubators will be filled with tracer-labeled algae or fecal material mimicking the diet and waste products of animal plankton. The tracers allow the researchers to follow the material through the microbial food web, and simultaneously determine the net release of carbon dioxide during the incubations. Using a combination of genetic analysis and novel analytical techniques, the researchers will be able to identify the organisms involved in the decay processes and rates at which changes occur at the single-cell level. Results will shed light on these understudied biological phenomena and contribute to an improved understanding of the global carbon cycle. In addition to novel advancements in oceanographic technology, the research supports graduate and undergraduate student education, and public outreach through partnerships with the Virginia Aquarium and National Ocean Sciences Bowl to increase ocean science literacy. In this project, researchers will study the organisms, mechanisms, and physical and ecological factors that modulate the remineralization of organic material in the deep sea. The methods include using in situ incubations of well-defined and stable isotope-labeled sources of organic carbon (live and dead phytoplankton and fecal pellets of zooplankton) with natural microbial communities. The incubations will take place northeast of Cape Hatteras, a region characterized by strong offshore transport of phytoplankton carbon. Net carbon dioxide release rates will be measured over time by conversion of Carbon-13 labeled organic carbon to 13CO2 . The dependence of degradation rates on the source material, seasonality, oxygen concentration, and the type of microbial colonizers will be assessed. Parallel laboratory experiments will elucidate the exact shape of the time course of carbon release by phytoplankton into dissolved organic and inorganic fractions as well as determine how representative laboratory and ship-board generated values are relative to those obtained in situ. Target eukaryotic and prokaryotic taxa are identified by fluorescence in-situ hybridization (FISH) after the incubations and individually interrogated using Raman microspectrometry to investigate the relative Carbon-13-enrichment rates in organisms assimilating labeled detrital carbon. This multi-faceted approach will provide better constrained parameters for ecosystem and biological pump models and shed light on carbon balances of the deep sea. The research contributes to the development of new oceanographic technology, including new deep-sea incubators and application of single-cell Raman microspectrometry to natural microbial communities.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.

通过了解生物泵（海洋从大气层到海洋内部和海底沉积物的生物学驱动的隔离），科学家们知道，世界上的海洋吸收的二氧化碳比返回大气层吸收更多的二氧化碳。 尽管对碳转移到深海的主要负责生物过程知之甚少，但对于碳到达深海时发生的微生物衰变以及随后发生的回忆过程的了解很少。 研究人员将使用新设计的深海孵化器部署在美国东海岸，探索微生物群落和回忆过程，这些过程会改变深海中的碳。孵化器将充满示踪标记的藻类或粪便材料，模仿动物浮游生物的饮食和废物。示踪剂使研究人员可以通过微生物食品网遵循材料，同时确定孵育过程中二氧化碳的净释放。利用遗传分析和新颖的分析技术的结合，研究人员将能够确定衰减过程中涉及的生物和单细胞水平发生变化的速率。结果将阐明这些研究经过研究的生物学现象，并有助于改善对全球碳循环的理解。除了海洋技术方面的新进步外，该研究还通过与弗吉尼亚水族馆和国家海洋科学碗的合作伙伴关系来支持研究生和本科生教育，以及公众宣传，以提高海洋科学素养。在该项目中，研究人员将研究调节深海有机材料的生物，机制和物理和生态因素。这些方法包括使用天然微生物群落的有机碳（活浮游植物和死亡浮游生物和浮游生物颗粒）的原位孵育。该孵化将发生在哈特拉斯角（Cape Hatteras）东北，该地区的特征是浮游植物碳的近海运输。二氧化碳释放速率将随着时间的推移通过将有机碳转换为13CO2来测量。将评估降解速率对原始材料，季节性，氧气浓度和微生物殖民者类型的依赖性。平行的实验室实验将阐明浮游植物释放碳释放的精确形状，并确定代表性实验室和船板生成的值与现场获得的值相关。孵育后通过荧光原位杂交（FIS）鉴定靶真主核和原核生物分类群，并使用拉曼微光谱法进行了单独询问，以研究吸收贴贴碎屑碳的生物体中的相对碳13-富度。这种多面方法将为生态系统和生物泵模型提供更好的约束参数，并阐明深海的碳平衡。这项研究有助于开发新的海洋学技术，包括新的深海孵化器以及单细胞拉曼微光谱法对天然微生物群落的应用。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛影响的审查标准通过评估来通过评估来获得支持的。