Picophytoplankton and bacteria abundances analyzed with flow cytometry (FCM) from CCE LTER process cruises the California Current region, 2006 - 2017.

Picophytoplankton populations and non-pigmented prokaryotes are sampled within the California Current Ecosystem (CCE) for abundances at various depths. Seawater is collected from Niskin bottles and cells are fixed in the field aboard the process cruises (since 2006, ongoing) with paraformaldehyde, and stained with a DNA-specific dye back in the laboratory. The cells are enumerated by an Altra flow cytometer (with a syringe pump for volumetric sample delivery) simultaniously with argon ion lasers, to distinguish three major populations of photoautotrophs (Prochlorococcus, Synechococcus, and pico-eukaryotes) and the assemblage of heterotrophic prokaryotes collectively referred to as H-Bact.