Collaborative Research: Southern Ocean Iron Experiment (SOFeX): Mesoscale Iron Fertilization Effects on Plankton Community Structure, Growth and Zooplankton Grazing

合作研究：南大洋铁实验（SOFeX）：中尺度铁施肥对浮游生物群落结构、生长和浮游动物放牧的影响

• 批准号: 0000330
• 负责人: Sallie Chisholm
• 金额: $ 17.9万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-15 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0000330&HistoricalAwards=false
• 关键词: Collaborative; Research; Southern; Ocean; Iron

The Southern Ocean is a critical region for understanding the role of the oceans in global carbon cycling and its potential to regulate climate change. Besides being an area of high influx of atmospheric carbon and deep water formation, the persistently high concentrations of major nutrients in Antarctic circumpolar waters represent the largest pool of unrealized primary production potential in the oceans. This project is part of a larger effort to test the hypothesis that iron availability limits phytoplankton production and biomass accumulation, nutrient utilization and C02drawdown in the Southern Ocean. Drs. Landry, Chisholm and Bidigare, will contribute by investigating the effects of iron enrichment and silicate availability on the species composition and size structure of the plankton community and taxon-specific growth rates and fluorescence responses of the phytoplankton. Functional and taxonomic components of the plankton community from bacteria to mesozooplankton will be quantified by a combination of flow cytometry, taxon-specific pigments, video image-analysis microscopy and optical plankton counting. In addition, they will use dilution and gut fluorescence techniques to determine micro- and mesozooplankton contributions to grazing and to evaluate grazing as an alternate control mechanism preventing significant net growth of some or all of the phytoplankton populations. The research will bring a community perspective to the interpretation of these in situ fertilization experiments which is essential for a mechanistic understanding of the biological and geochemical responses.

南大洋是了解海洋在全球碳循环中的作用及其调节气候变化的潜力的关键区域。除了是大气碳和深水形成的地区外，南极圆形水域中持续高浓度的主要营养素也是海洋中最大的未实现的主要生产潜力池。该项目是测试以下假设的更大努力的一部分，即铁的可用性限制了浮游植物的产量和生物质积累，养分利用和C02Drawdown在南海。 博士。 Landry，Chisholm和Bidigare将通过研究铁富集和硅酸盐的可用性对浮游生物社区物种组成和大小结构的影响以及浮游植物浮游植物的荧光反应。浮游生物群落的功能和分类成分将通过流式细胞仪，分类群特异性色素，视频图像分析显微镜和光学浮游生物计数的结合来量化。此外，他们将使用稀释和肠道荧光技术来确定对放牧的微观和中龙兰克顿贡献，并评估放牧作为一种替代控制机制，以防止某些或所有浮游植物种群的显着净增长。这项研究将使社区观点对这些原位受精实验的解释产生观点，这对于对生物学和地球化学反应的机械理解至关重要。