Algae report number 5, 2020

Type: Report
Author: Marie Johansen, Maria Karlberg


Both the species diversity and total cell numbers were moderate at both stations in the Skagerrak at the time of sampling. Diatoms dominated with a combination of species. Several fluorescence peaks were recorded at different depths. Samples from these depths contained almost exclusively diatoms. The diatom Guinardia flaccida was found in high concentrations at all peaks with a clear domination at the northern stations. The two stations in the Kattegat had low total cell concentrations and low species diversity. The larger cells in the samples were dominated by dinoflagellates. The genus Tripos (previously Ceratium) was most common at these stations. The integrated chlorophyll concentrations were low but within normal for the month at all stations along the west coast. The species diversity was generally high in the Baltic Sea, but the total cell numbers were low except for the stations dominated by colony forming cyanobacteria. The stations in the southern part of the Baltic Sea had the highest concentrations of colony forming cyanobacteria. The filamentous cyanobacteria Aphanizomenon flosaquae was found at most stations and even in moderate concentrations in the northern part. The integrated chlorophyll concentrations were within normal at all stations except at RefM1V1 (close to the coast) where it was above what is normal for the month.