Phytoplankton

Materials and Methods (revised):

Water bottle sampling between June 5th and June 12th, mostly in the morning:

  • 8 mixed samples from the surface, 5 m and 10 m depth;

  • 7 samples from 20 m (below the thermocline);

  • 1 sample at station 9017 from 1m;

  • 2 samples at stations 9009 and 9010 from 100m instead of 20 m due to sampling errors;

    • Preservation:

  • Samples were preserved immediately with 0.5 - 1.0 ml acid Lugol´s solution (Willén, 1962) per 200 ml sample volume;

  • Stored in colourless, tightly-stoppered glass bottles.

  • Stored dark and cool (ca. +4°C);

    • Determination within half a year after sampling:

  • Utermöhl technique (Utermöhl, 1958, Edler, 1979);

  • Settling and counting procedure was done according to the Guidelines for the Baltic Monitoring Programme (Helcom, 1988)

    • Taxa and species: (Species were grouped into 7 main categories, based on size.)

  • Cyanobacteria

  • Dinoflagellates

  • Bacillariophyceae

  • Chlorophyta sensu lato

  • Cryptophyceae

  • Chrysophyceae

  • unidentified (flagellates, cyanobacteria or small chlorophyta)

    • Literature:

    Edler, L. 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists Publ. 5: 1-39.

    Helcom 1988. Guidelines for the Baltic Monitoring Programme. The third stage. Part D. Biological Determinands. Baltic Sea Environment. Proceedings 27 D. Helsinki Commission. 161 pp.

    Utermöhl, H. 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitt. int. Verein. theor. angew. Limnol. 9: 1-38.

    Willén, T. 1962. Studies on the phytoplankton of some lakes connected with or recently isolated from the Baltic. Oikos 13: 169 - 199.

    Institue of Baltic Sea Research
    Seestrasse 15
    D18119 Rostock - Warnemünde
    Germany
    Lutz Postel, 28-3-01       sample analysis by Susanne Busch