Microzooplankton grazing experiments: What is going on during incubation?

Abstract

Microzooplankton grazing was measured at different time intervals during incubation. Grazing is normally measured in 24 hour experiments following the dilution method. However, knowledge about changes in grazing during incubation is lacking. Time-series experiments were performed in order to study changes in grazing upon picoplankton. Sampling took place during 24-30 hours, and every 2 hours in order to follow grazing variability. Higher grazing rates were found during the first 6 hours of the experiment, mainly upon picoeukaryote cells and increasing during night. We also show opposite patterns between growth and grazing during incubation. Grazing observed clearly showed an important variability during the course of experiments deserving further research in order to improve grazing assessment in the ocean.