Phytoplankton DNA metabarcoding in four sectors of the SW Atlantic in the context of the global ocean

Federico M. Ibarbalz; Juan J. Pierella Karlusich; Sergio Velasco Ayuso; Natalia Visintini; Lionel Guidi; Chris Bowler; Pedro Flombaum

doi:10.25260/EA.22.32.3.0.1812

Authors

Federico M. Ibarbalz Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales. Buenos Aires, Argentina. CONICET-Universidad de Buenos Aires. Centro de Investigaciones del Mar y la Atmósfera (CIMA). Buenos Aires, Argentina. Institut FrancoArgentin d'Études sur le Climat et ses Impacts, International Research Laboratory (IRL-IFAECI/CNRS-CONICET-UBA). Buenos Aires, Argentina. Instituto Universitario de Seguridad Marítima, Prefectura Naval Argentina. Buenos Aires, Argentina. Institut de Biologie de l’École Normale Supérieure (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université de Recherche Paris Sciences et Lettres (Université PSL). Paris, France
Juan J. Pierella Karlusich Institut de Biologie de l’École Normale Supérieure (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université de Recherche Paris Sciences et Lettres (Université PSL). Paris, France. Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France. FAS Division of Science, Harvard University, Cambridge, MA.
Sergio Velasco Ayuso Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales. Buenos Aires, Argentina. CONICET-Universidad de Buenos Aires. Centro de Investigaciones del Mar y la Atmósfera (CIMA). Buenos Aires, Argentina. Institut FrancoArgentin d'Études sur le Climat et ses Impacts, International Research Laboratory (IRL-IFAECI/CNRS-CONICET-UBA). Buenos Aires, Argentina. Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Ecología Genética y Evolución. Buenos Aires, Argentina
Natalia Visintini Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales. Buenos Aires, Argentina. CONICET-Universidad de Buenos Aires. Centro de Investigaciones del Mar y la Atmósfera (CIMA). Buenos Aires, Argentina. Institut FrancoArgentin d'Études sur le Climat et ses Impacts, International Research Laboratory (IRL-IFAECI/CNRS-CONICET-UBA). Buenos Aires, Argentina
Lionel Guidi Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France. 7 Sorbonne Université, Centre National de la Recherche Scientifique, Laboratoire d’Océanographie de Villefranche (LOV), Villefranche-surMer, France
Chris Bowler Institut de Biologie de l’École Normale Supérieure (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université de Recherche Paris Sciences et Lettres (Université PSL). Paris, France. Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara GOSEE, Paris, France
Pedro Flombaum CONICET-Universidad de Buenos Aires. Centro de Investigaciones del Mar y la Atmósfera (CIMA). Buenos Aires, Argentina. Institut FrancoArgentin d'Études sur le Climat et ses Impacts, International Research Laboratory (IRL-IFAECI/CNRS-CONICET-UBA). Buenos Aires, Argentina. Instituto Universitario de Seguridad Marítima, Prefectura Naval Argentina. Buenos Aires, Argentina. Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Ecología Genética y Evolución. Buenos Aires, Argentina

DOI:

https://doi.org/10.25260/EA.22.32.3.0.1812

Keywords:

phytoplankton, Southwest Atlantic Ocean, primary productivity, biodiversity, 18S rRNA gene

Abstract

The Southwest Atlantic Ocean (SWAO) is a spatially dynamic region with a remarkably high primary productivity. An exhaustive identification of the members of its phytoplankton community is a key step to understand the processes that sustain this ecosystem. Here, we provide a community composition analysis of eukaryotic phytoplankton in four SWAO sectors. We gathered 18S rRNA gene metabarcoding data and complemented it with confocal microscopy images, both from the Tara Oceans expedition in late spring 2010. Our work showed local and regional variation across three different size fractions that reflect the complexity of this region. Diversity decreased along temperature and latitudinal gradients, but also showed intricate patterns of occurrences across samples, suggesting that multiple factors shape the community structure. Samples resembled communities from other temperate regions and showed an increasing influence by cold waters from the Southern Ocean towards higher latitudes. These results complement previous regional studies that used other methods such as microscopy or pigment analysis. Our study contributes to the beginning of genomic-based surveys of plankton communities in the SW Atlantic and calls for further work in the region to enhance ecosystem monitoring and projections in the context of global change.

Ph: Marin LE ROUX (polaRYSE - Fondation Tara Ocean)

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