Caracciolo M. auteur aut IRD Rigaut-Jalabert F. auteur aut IRD Romac S. auteur aut IRD Mahe F. auteur aut IRD Forsans S. auteur aut IRD Gac J. P. auteur aut IRD Arsenieff L. auteur aut IRD Manno M. auteur aut IRD Chaffron S. auteur aut IRD Cariou Thierry auteur aut IRD Hoebeke M. auteur aut IRD Bozec Y. auteur aut IRD Goberville E. auteur aut IRD Le Gall F. auteur aut IRD Guilloux L. auteur aut IRD Baudoux A. C. auteur aut IRD de Vargas C. auteur aut IRD Not F. auteur aut IRD Thiebaut E. auteur aut IRD Henry N. auteur aut IRD Simon N. auteur aut IRD text journalArticle eng text/pdf reformatted digital access Major seasonal community reorganizations and associated biomass variations are landmarks of plankton ecology. However, the processes of plankton community turnover rates have not been fully elucidated so far. Here, we analyse patterns of planktonic protist community succession in temperate latitudes, based on quantitative taxonomic data from both microscopy counts (cells >10 mu m) and ribosomal DNA metabarcoding (size fraction >3 mu m, 18S rRNA gene) from plankton samples collected bimonthly over 8 years (2009-2016) at the SOMLIT-Astan station (Roscoff, Western English Channel). Based on morphology, diatoms were clearly the dominating group all year round and over the study period. Metabarcoding uncovered a wider diversity spectrum and revealed the prevalence of Dinophyceae and diatoms but also of Cryptophyta, Chlorophyta, Cercozoa, Syndiniales and Ciliophora in terms of read counts and or richness. The use of morphological and molecular analyses in combination allowed improving the taxonomic resolution and to identify the sequence of the dominant species and OTUs (18S V4 rDNA-derived taxa) that drive annual plankton successions. We detected that some of these dominant OTUs were benthic as a result of the intense tidal mixing typical of the French coasts in the English Channel. Our analysis of the temporal structure of community changes point to a strong seasonality and resilience. The temporal structure of environmental variables (especially Photosynthetic Active Radiation, temperature and macronutrients) and temporal structures generated by species life cycles and or species interactions, are key drivers of the observed cyclic annual plankton turnover. specialized annual succession DNA metabarcoding marine protists temporal variability time-series data Western English Channel FRANCE MANCHE ROSCOFF 034 036 [Early acces] [23 p.] 2022 0962-1083 https://www.documentation.ird.fr/hor/fdi:010085284 10.1111/mec.16539 0962-1083 [F B010085284] https://www.documentation.ird.fr/hor/fdi:010085284 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2022-09/010085284.pdf IRD - Base Horizon / Pleins textes 2022-09-02 2025-02-24 fdi:010085284 fre