Collaborative Research: Synergistic Effects of Iron, Carbon Dioxide and Temperature on the Fate of Nitrate: Implications for Future Changes in Export Production in the Southern Oce

该奖项为NSF极地计划办公室南极生物和生态系统计划的“合作研究：铁、二氧化碳和温度对硝酸盐命运的协同效应：对南大洋出口生产未来变化的影响”提供支持。该项目将使用一种新的研究方法组合来评估温度、二氧化碳和铁对三个生态和生物地球化学关键的南大洋浮游植物功能群的影响：大型中心硅藻、小型羽状硅藻和南极洲棕囊藻。智力优势：南极周围的南大洋正在经历几个变化，包括温度和二氧化碳含量的上升，以及生物可利用铁水平的变化。该项目的目标是了解这三个变量的单独和综合影响如何影响南大洋浮游植物群落结构，并确定这些组合水平的反应如何与营养生理和基因表达水平上的基本细胞反应相联系。研究小组将专注于三种不同类型的海藻：大硅藻和小硅藻，以及裸子植物南极洲棕囊藻。在快速变化的南极海洋环境中，这三个主要藻类之间的变化对营养和碳生物地球化学产生了非常不同的后果。然而，这些由环境驱动的社区转变的机制基础尚不清楚。该项目包括一个带有南极隔离的美国实验室部分，在麦克默多站进行实地研究，然后在南极绕极洋流正南方的上升流区进行一次机会巡航。这项研究还包括从野外和实验环境中收集和分析环境基因表达数据，或元转录组学。这些转录本将在与环境相关的条件下产生，因此除了上述三个组外，还将包含对破译几个新测序的极地浮游植物物种基因组至关重要的信息。广泛影响：该奖项将培训本科生和研究生，并为博士后研究人员提供部分支持。该团队还将在暑假期间在J.Craig Venter Institute接待高中教师，并制定与该项目相关的实践教学计划，以促进教师培训和学习。此外，基因组测序信息将向公众开放，预计作为该项目的一部分开发的统计技术将对更广泛的研究界有用。

This award provides support for "Collaborative Research: Synergistic Effects of Iron, Carbon Dioxide, and Temperature on the Fate of Nitrate: Implications for Future Changes in Export Production in the Southern Ocean" from the Antarctic Organisms and Ecosystems program in the Office of Polar Programs at NSF. The project will use a novel combination of research approaches to evaluate the effects of temperature, carbon dioxide, and iron on three ecologically- and biogeochemically-critical Southern Ocean phytoplankton functional groups: Large centric diatoms, small pennate diatoms, and Phaeocystis antarctica. Intellectual Merit: The Southern Ocean around Antarctic is undergoing several changes including increased temperature and carbon dioxide content, as well as changing levels of biologically available iron. The project goals are to understand how the individual and combined influences of these three variables affect Southern Ocean phytoplankton community structure, and to determine how these assemblage-level responses are linked to fundamental cellular responses at the levels of nutrient physiology and gene expression. The research team will focus on three different types of marine algae: large and small diatoms, and the prymnesiophyte, Phaeocystis antarctica. Shifts between these three major algal groups have very different consequences for nutrient and carbon biogeochemistry in the rapidly changing Antarctic marine environments. However, the mechanistic underpinnings of these environmentally-driven community shifts are not known. The project includes a US-based laboratory component with Antarctic isolates, field study at McMurdo Station, and then a cruise of opportunity in the upwelling areas directly south of the Antarctic Circumpolar Current. The study also includes collection and analysis of environmental gene expression data, or meta-transcriptomics, both from the field and experimental settings. The transcriptomes will be generated under environmentally relevant conditions and will thus contain information critical for decoding the genomes of several newly sequenced polar phytoplankton species in addition to the three groups highlighted above.Broader Impact: The award will train undergraduate and graduate students, and also provide partial support for a post-doctoral researcher. The team will also promote teacher training and learning by hosting high-school teachers at the J. Craig Venter Institute during the summer, and development of hands-on lesson plans related to the project. Additionally, genomic sequencing information will be made publically accessible, and it is envisioned that statistical techniques developed as part of this project will be of use to the wider research community.