Sampling Constraints and Variability in the Analysis of Bacterial Community Structures in the Sea Surface Microlayer

The sea surface microlayer (SML) is a thin film located at the interface between oceans and atmosphere. In this study, three SML samplers—polycarbonate membrane (PC), glass plate (GP), drum sampler (DS)—were used to collect microbiological DNA samples for molecular analysis. Among samplers, DS only took half time sample compared GP while PC were able thinnest depth. Biological matter distinct bacterial communities in apparent during low wind conditions collected by samplers. Signs of biological [transparent exopolymer particles (TEP) chlorophyll-a concentrations] depletion, an increased similarity underlying water (UW), more pronounced high speed DS. had lower enrichment than with UW. depletion periods chl-a concentrations SML. contrast, was consistently community from that UW, regardless conditions. Bacterial obtained samplers showed relatively consistent patterns structure, despite large fluctuations seasons (summer vs. winter) layers (SML UW) being observed. Although no SML-specific taxon detected comparison representation taxonomic groups each suggested certain taxa (15 orders) specifically enriched or depleted SML, especially belonging Actinobacteria, Cyanobacteria, Deferribacteria, Proteobacteria . This trend sampling method, implying these are key biogeochemical processes occurring air-sea interface.