Baltic proper, Northern Baltic Sea, Gotland Basin, Bornholm Basin, Arkona 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)

Chlorophyll pigment concentrations in water bodies

Discrete water samplers; spectrophotometers

The aim of researches is to determine water trophic (biological productivity) level of the Baltic Sea and it's year-to-year and seasonal dynamics. The amount of the chlorophyll a is an important characteristic of the phytoplankton photosynthesis activity which helps to determine the amounts of phytoplankton biomass and the trophic level of a water body. In accordance with the national and international Baltic Sea monitoring (HELCOM) programme monitoring cruises have been fulfilled with Lithuanian research vessel 'Vejas'. During the period 1993-1999 investigations of chlorophyll a have been carried out in the Baltic proper and Lithuanian marine waters every season and in recreational zone - every month. Since 2000 the researches have been carried out only in the Lithuanian territorial and exclusive economic zone. 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 (written form) and is saved on hard disk.

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

LT-91149
Lithuania