title: Defining seasonal marine microbial community dynamics.
abstract: Here we describe, the longest microbial time-series analyzed to date using high-resolution 16S rRNA tag pyrosequencing of samples taken monthly over 6 years at a temperate marine coastal site off Plymouth, UK. Data treatment effected the estimation of community richness over a 6-year period, whereby 8794 operational taxonomic units (OTUs) were identified using single-linkage preclustering and 21 130 OTUs were identified by denoising the data. The Alphaproteobacteria were the most abundant Class, and the most frequently recorded OTUs were members of the Rickettsiales (SAR 11) and Rhodobacteriales. This near-surface ocean bacterial community showed strong repeatable seasonal patterns, which were defined by winter peaks in diversity across all years. Environmental variables explained far more variation in seasonally predictable bacteria than did data on protists or metazoan biomass. Change in day length alone explains >65% of the variance in community diversity. The results suggested that seasonal changes in environmental variables are more important than trophic interactions. Interestingly, microbial association network analysis showed that correlations in abundance were stronger within bacterial taxa rather than between bacteria and eukaryotes, or between bacteria and environmental variables.
authors.affiliation: Plymouth Marine Laboratory, Prospect Place, Plymouth, UK. gilbertjack@anl.gov
authors.forename: Jack A
authors.initials: JA
authors.lastname: Gilbert
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Steele
authors.forename: J Gregory
authors.initials: JG
authors.lastname: Caporaso
authors.forename: Lars
authors.initials: L
authors.lastname: Steinbrück
authors.forename: Jens
authors.initials: J
authors.lastname: Reeder
authors.forename: Ben
authors.initials: B
authors.lastname: Temperton
authors.forename: Susan
authors.initials: S
authors.lastname: Huse
authors.forename: Alice C
authors.initials: AC
authors.lastname: McHardy
authors.forename: Rob
authors.initials: R
authors.lastname: Knight
authors.forename: Ian
authors.initials: I
authors.lastname: Joint
authors.forename: Paul
authors.initials: P
authors.lastname: Somerfield
authors.forename: Jed A
authors.initials: JA
authors.lastname: Fuhrman
authors.forename: Dawn
authors.initials: D
authors.lastname: Field
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics; D018407:Bacterial Physiological Phenomena; D044822:Biodiversity; D004777:Environment; D009792:Oceans and Seas; D017440:Photoperiod; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012621:Seasons; D006113:United Kingdom
chemical_list: D012336:RNA, Ribosomal, 16S