Appendicularians and marine snow <i>in situ</i> vertical distribution in Argentinean Patagonia

Abstract Detailed in situ vertical and temporal distribution of appendicularians, marine snow, fecal pellets, nano- microplankton were recorded simultaneously with environmental data the San Jorge Gulf, Argentinean Patagonia (45°–47°S). Data taken at a fixed station over 36 h February 2014 an autonomous Video Plankton Recorder FlowCAM®. The water column was thermally stratified pycnocline ~ 40 m. Appendicularians dominated upper 65 m condensed pattern above high chlorophyll concentrations, matching subsurface maximum layer 20 Our results suggest absence migration appendicularians. Marine strongly correlated showed concentrations pycnocline, whereas pellets from krill distributed throughout column. Discarded houses appendicularians or their mucus fragments main components snow aggregates, phytoplankton, detritus also contributing. Nanoplankton microplankton, patterns that might depend on local grazing pressure advective processes. study, first one region using underwater imagery, emphasizes leading contribution to aggregates Gulf potential implications bentho-pelagic coupling.