Abundance of dinoflagellates and ciliates at time series station Helgoland Roads, North Sea, in 2009

Standard Uthermöhl counts of fixed samples on Zeiss Axiovert 135 inverted microscope. Fixation: Acid Lugol 2% final concentration. The counts were carried out on subsamples of the work-daily Helgoland Roads phytoplankton samples, therefore sampling depth, and time of day are the same as in the phytoplankton counts.