Microzooplankton data of NEREA Augmented Observatory

Samples were collected at the selected depth using Niskin bottles and immediately fixed with Lugol's solution (1%). Quantitative analysis is carried out using an inverted microscope after the settling of a variable volume of sample (Utermhöl, 1958). Volumes vary in relation to the number of cells present in the sample. At first, 100mL are settled form each sample and cells enumerated. The volume of sample is considered sufficient if it is possible to count at least 100 cells on a transect. Otherwise additional volume is settled on top of the same chamber up to a maximum of 250mL. Counting is done over the whole sedimentation chamber or half of it, depending on the characteristics of the sample.