Enrichment of saccharides at the air–water interface: a quantitative comparison of sea surface microlayer and foam

Environmental context Saccharides contribute substantially to dissolved organic carbon in the ocean and are enriched at surface. In this study, we demonstrate that saccharides more persistent whitecap foam compared sea The maturation of bubbles air–water interface is thus expected enhance enrichment matter surface ultimately spray aerosol forms when burst Rationale Organic accumulates Herein, provide first quantitative assessment compare microlayer (SSML) during a 9 day mesocosm experiment involving phytoplankton bloom generated Marine Aerosol Reference Tank (MART). Methodology Free monosaccharides were quantified directly, total determined following mild acid hydrolysis oligo/polysaccharide component was as difference between free monosaccharides. Results Total contributed significant fraction (DOC), accounting for 13% DOC seawater, 27% SSML 31% foam. Median factors (EFs), calculated ratio concentrations relative sodium or ranged from 1.7 6.4 2.1–12.1 Based on median EFs, xylitol, mannitol, glucose, galactose, mannose, xylose, fucose, rhamnose ribose than SSML. Discussion greatest EFs coincided with high chlorophyll levels, indicating increasing blooms. Higher enrichments over indicate active compounds become increasingly bubble film surfaces. These findings help explain how marine becomes highly by bursting