SGER: Southern and Coastal Extent of Picophytoplankton Populations in the South Pacific

SGER：南太平洋超微型浮游植物种群的南部和沿海范围

• 批准号: 0847890
• 负责人: Lisa Moore
• 金额: --
• 依托单位: University of Southern Maine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-11-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0847890&HistoricalAwards=false
• 关键词: SGER; Southern; Coastal; Extent; Picophytoplankton

The most abundant and ubiquitous members of the marine phytoplankton belong to two cyanobacterial genera, Synechococcus and Prochlorococcus, which together contribute more than half of the primary productivity in the open ocean. Each of these genera, which form a distinct picophytoplankton clade within the marine cyanobacteria, can be further subdivided into multiple phylogenetic clades (referred to as genotypes or ecotypes), some of which have clear physiological characteristics that can be related to their ecological distributions. However, the boundaries of the horizontal distributions of the various genotypes are not fully understood, and discrepancies between studies in the South Atlantic require further examination of the picophytoplankton distributions, particularly of the Prochlorococcus populations. In a research cruise during Dec 2008 to the Patagonia shelf region from ~40 deg S, 57deg W to ~53 deg S, 55 deg W near the Falkland Islands, the PI will be able to examine the southern extent of picophytoplankton populations as well as the distributions across the shelf break front going east into oligotrophic waters. At stations representing different water types, samples will be collected for flow cytometric analysis of picophytoplankton populations, will be filtered for later qPCR analysis of Prochlorococcus and Synechococcus ecotypes, and will be cryopreserved for isolations using high throughput culture methods.This SGER project will provide a new dataset of the southern and coastal extent of picophytoplankton populations, and possibly address the question of whetherProchlorococcus populations are extending further south into colder waters than initially observed more than a decade ago. Additionally, it will enable a MS student to participate in the research cruise and get experience with field research, provide funds for supplies and shipping samples, and provide a MS student stipend to analyze the samples.

海洋浮游植物中最丰富、最普遍的成员属于两个蓝藻属：聚球藻属和原绿球藻属，它们共同贡献了公海初级生产力的一半以上。这些属中的每一个都在海洋蓝藻中形成了独特的微型浮游植物分支，可以进一步细分为多个系统发育分支（称为基因型或生态型），其中一些具有与其生态分布相关的明确的生理特征。然而，各种基因型水平分布的界限尚未完全了解，南大西洋研究之间的差异需要进一步检查超微型浮游植物的分布，特别是原绿球藻种群的分布。在 2008 年 12 月从南纬 57 度左右到福克兰群岛附近南纬 57 度左右到南纬 55 度左右的巴塔哥尼亚大陆架地区进行的一次研究巡航中，PI 将能够检查微型浮游植物种群的南部范围以及整个大陆架的分布断裂前沿向东进入贫营养水域。在代表不同水类型的站点，将收集样本用于对超微型浮游植物种群进行流式细胞术分析，将进行过滤以用于随后对原绿球藻和聚球藻生态型进行 qPCR 分析，并将使用高通量培养方法进行冷冻保存以进行分离。该 SGER 项目将提供南部和沿海超微型浮游植物种群的新数据集，并可能解决原绿球藻种群是否进一步向南延伸到更冷地区的问题水域比十多年前最初观察到的要大。此外，它将使理学硕士学生能够参加研究巡航并获得现场研究经验，提供用品和运输样品的资金，并提供理学硕士学生分析样本的津贴。