Seasonality of the Microbial Community Composition in the North Atlantic
Seasonality of the Microbial Community Composition in the North Atlantic
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DOI：
10.3389/fmars.2021.624164
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发表时间：
2021-02-05
影响因子：
3.7
通讯作者：
Giovannoni, Stephen
中科院分区：
文献类型：
--
作者：
Bolanos, Luis M.;Choi, Chang Jae;Giovannoni, Stephen
浮游生物群落是海洋环境中生命的基础，对地球化学循环有着深远的影响。在北大西洋，季节性驱动着水柱生态的年度转变。由于这些转变，浮游植物每年春天都会大量繁殖，这是地球上生产力的主要生物脉冲之一。利用全球卫星成像能力，对春季水华的时间和地理分布以及由此产生的生物量积累进行了大量研究。然而，细尺度的分类组成，空间分布，季节性变化，生态与异养浮游细菌的相互作用的变化在很大程度上仍然是未知的。北大西洋气溶胶和海洋生态系统研究（NAAMES）进行了四次跨大西洋断面调查，以确定浮游生物生态系统在年度水华周期中的特征。利用基于16S rRNA基因的群落结构分析了浮游生物群落的时空变化。浮游植物和浮游细菌组成的季节性是明显的整个水柱，与水文起源的变化依赖。从冬季到春季，在亚热带和亚极地次区域，浮游植物从蓝细菌和picoeukaryotic绿色藻类的优势，各种光合真核生物。到了秋天，亚热带地区被蓝细菌所控制，而各种各样的真核生物则控制了亚极地地区。浮游细菌也受到地理分区的强烈影响。SAR11是海洋表层最丰富的细菌，在亚热带的丰富度高于亚极地。SAR11亚支在两个亚区之间的分布存在差异。亚支Ia.1和Ia.3共同出现在亚极地，而Ia.1主要分布在亚热带。在亚热带地区，在冬季，SAR 11亚支“II”和1c.1的相对丰度升高，在中上层。在冬季，SAR202亚支普遍存在于深海层，也是中上层的优势成员。协变网络分析证实了浮游生物群落的大规模地理组织，并提供了深入了解浮游细菌的垂直分布。这项研究代表了迄今为止在北大西洋西部的微生物概况最全面的调查，揭示了鲜明的季节性差异的组成和丰富性所界定的生态地理分布的浮游生物群落。
Planktonic communities constitute the basis of life in marine environments and have profound impacts in geochemical cycles. In the North Atlantic, seasonality drives annual transitions in the ecology of the water column. Phytoplankton bloom annually in spring as a result of these transitions, creating one of the major biological pulses in productivity on earth. The timing and geographical distribution of the spring bloom as well as the resulting biomass accumulation have largely been studied using the global capacity of satellite imaging. However, fine-scale variability in the taxonomic composition, spatial distribution, seasonal shifts, and ecological interactions with heterotrophic bacterioplankton has remained largely uncharacterized. The North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) conducted four meridional transects to characterize plankton ecosystems in the context of the annual bloom cycle. Using 16S rRNA gene-based community profiles we analyzed the temporal and spatial variation in plankton communities. Seasonality in phytoplankton and bacterioplankton composition was apparent throughout the water column, with changes dependent on the hydrographic origin. From winter to spring in the subtropic and subpolar subregions, phytoplankton shifted from the predominance of cyanobacteria and picoeukaryotic green algae to diverse photosynthetic eukaryotes. By autumn, the subtropics were dominated by cyanobacteria, while a diverse array of eukaryotes dominated the subpolar subregions. Bacterioplankton were also strongly influenced by geographical subregions. SAR11, the most abundant bacteria in the surface ocean, displayed higher richness in the subtropics than the subpolar subregions. SAR11 subclades were differentially distributed between the two subregions. Subclades Ia.1 and Ia.3 co-occurred in the subpolar subregion, while Ia.1 dominated the subtropics. In the subtropical subregion during the winter, the relative abundance of SAR11 subclades "II" and 1c.1 were elevated in the upper mesopelagic. In the winter, SAR202 subclades generally prevalent in the bathypelagic were also dominant members in the upper mesopelagic zones. Co-varying network analysis confirmed the large-scale geographical organization of the plankton communities and provided insights into the vertical distribution of bacterioplankton. This study represents the most comprehensive survey of microbial profiles in the western North Atlantic to date, revealing stark seasonal differences in composition and richness delimited by the biogeographical distribution of the planktonic communities.