Baltic proper, Northern Baltic Sea, Gotland Basin, Bornholm Basin, Arkona Sea during the period 1985-1990 (data set limits: 54 39 - 56 02N; 14 05 - 22 11E); Baltic Proper, Gdansk Basin, Gotland Basin during the period 1993-1999 (data set limits: 54 54 - 57 22N; 18 24 - 21 05E); Lithuanian territorial and exclusive economic zone since 2000 (data set limits: 55 19 - 56 02N; 19 14 - 21 05E)

Phytoplankton generic abundance in water bodies; Phytoplankton taxonomic abundance in water bodies

Discrete water samplers; optical microscopes

The aim of researches is to investigate the community structure of the phytoplankton of the Baltic Sea, to evaluate year-to-year and seasonal dynamics of phytoplankton communities, as well as trends in phytoplankton development. The main objectives of the researches: to study phytoplankton species composition, to determine its abundance and biomass, to study algal bloom dynamics, to distinguish potentially toxic species of the phytoplankton, etc. In accordance with the national and international Baltic Sea monitoring (HELCOM) programme monitoring cruises have been fulfilled with Lithuanian research vessels 'Okeanografas', 'Vetra', 'Vejas'. Since 1985 seasonal investigations of phytoplankton have been carried out in a wide net of stations in national (Lithuanian territorial and economic waters) and international (Baltic proper) waters. Later the net of stations became more narrow and since 2000 researches in the Baltic Sea has been defined more exactly and has been carried out only in the territorial and exclusive economic zone of Lithuania. The samples are taken by mixing water (integrated samples) from the depths 0.5, 2.5, 5.0, 7.5 and 10 m. Preservation of material was performed according to HELCOM (1988). Before 1994 the samples were concentrated by a reversed filtration method, and a 0.02 ml counting chamber with a light microscope were used; since 1994 an inverted microscope technique was applied. Both methods were compared during the intercalibration (HELCOM). The data are fully quality controlled. Systematic certification of laboratories, participation in an international intercalibrations, internal control, introduced managing system for researches' quality, use of high quality reagents determine quality of data. All data is stored in archive (in table forms on paper) and is saved on hard disk.

Dr. I.Olenina (1998) Areas of the Kurshiu Marios Lagoon and the south-eastern Baltic coastal zone distinguished by the structures of the spring phytoplankton and complexes of plankton algae there / The environmental status of the Baltic Sea and Kurshiu Marios Lagoon (Articles in Lithuanian with English summaries), Virginija Cizauskiene; Dr. I.Olenina (2008) New for Lithuanian seacoast planktonic diatoms / Monograph: The Baltic Sea and its problems (Articles in Lithuanian with English summaries), N.Remeikaite, R.Nikzentaitiene; Wasmund N., Nausch G., Postel L., Witek Z., Zalewski M., Gromisz S., Lysiak-Pastuszak E., Olenina I., Kavolyte R., Jasinskaite A., Muller-Karulis B., Ikauniece A., Andrushaitis A., Ojaveer H., Kallast (2000) Trophic status of coastal and open areas of the south-eastern Baltic Sea based on nutrient phytoplankton data from 1993-1997. Baltic Sea Research Institute Warnemunde, Marine Science Reports No. 38 (2000)., ; Wasmund N., Andrushaitis A., Lysiak-Pastuszak E., Muller-Karulis B., Nausch G., Neumann T., Ojaveer H., Olenina I., Postel L., Witek Z. (2001) Trophic status of the south-eastern Baltic Sea: a comparison of coastal and open areas. Estuarine, Coastal and Shelf Science, Academic Press 2001.,

Department of Marine Research of the Environmental Protection Agency
Taikos Av. 26
Klaipeda

LT-91149
Lithuania