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

Autores/as

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

Palabras clave:

fitoplancton, Océano Atlántico suroeste, productividad primaria, biodiversidad, gen ARNr 18S

Resumen

El Océano Atlántico Suroeste es una región espacialmente dinámica, con sectores de alta productividad primaria. Un paso fundamental en la comprensión de los procesos que sostienen este ecosistema consiste en identificar a las especies del fitoplancton de forma exhaustiva. En el presente estudio analizamos la composición de la comunidad del fitoplancton eucariota en cuatro sectores del Océano Atlántico Suroeste. Para ello utilizamos datos de secuenciación masiva del gen ARNr 18S e imágenes de microscopía confocal de la expedición Tara Oceans, correspondientes a la primavera tardía del 2010. Las variaciones locales y regionales en las tres fracciones de tamaño que analizamos reflejan la complejidad de este ecosistema. Mientras la diversidad disminuyó hacia altas latitudes y bajas temperaturas, la comunidad presentó patrones intrincados en la composición de sus muestras, lo que sugiere la existencia de múltiples factores que determinan la estructura de la comunidad. Las muestras se asemejaron a las comunidades de otras regiones oceánicas templadas del planeta, aunque con una influencia de las aguas frías del Océano Antártico en el caso de las más australes. Estos resultados complementan estudios regionales previos en los que se utilizaron otros métodos como la microscopía o el análisis de pigmentos. Nuestro trabajo contribuye al comienzo de estudios genómicos de las comunidades de plancton en el Atlántico Suroeste y resalta la necesidad de contar con más estudios en la región para mejorar el monitoreo y las proyecciones de los ecosistemas en el contexto del cambio global.

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

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