Coexisting picoplankton experience different relative grazing pressures across an ocean productivity gradient.

ABSTRACT: Picophytoplankton populations [Prochlorococcus, Synechococcus (SYN), and picoeukaryotes] are dominant primary producers in the open ocean and projected to become more important with climate change. Their fates can vary, however, with microbial food web complexities. In the California Current Ecosystem, picophytoplankton biomass and abundance peak in waters of intermediate productivity and decrease at higher production. Using experimental data from eight cruises crossing the pronounced CCE trophic gradient, we tested the hypothesis that these declines are driven by intensified grazing on heterotrophic bacteria (HBAC) passed to similarly sized picophytoplankton via shared predators. Results confirm previously observed distributions as well as significant increases in bacterial

SUBMITTER: Landry MR 

PROVIDER: S-EPMC10622918 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature