Cyanobacterial blooms have decreased in the surface waters surrounding Finland. Cyanobacteria still occurs in moderate amounts mixed in the water column in the Gulf of Finland and in the Southern part of the Archipelago Sea, which means that in calm and warm weather conditions the occurrence of surface blooms might increase. In all the Finnish sea-areas, the surface temperature range from 15 to 17 (C) degrees. A small increase of Cyanobacteria blooms are expected to occur during the coming week.
Heavy winds have caused the cyanobacteria surface accumulations to disperse in the waters surrounding Finland. In the Gulf of Finland and in the southern Archipelago Sea cyanobacteria still occurs in moderate amounts mixed in the water column.
The surface temperatures have not changed significantly during the past week. The water temperature is mostly between 15 and 17 degrees in the sea-areas surrounding Finland.
In the Gulf of Finland and in the northern Baltic Proper, the potentially toxic cyanobacteria Aphanizomenon and Anabaena dominate the phytoplankton community. In the Gulf of Finland also other algae are common: dinoflagellates (Heterocapsa triquetra), euglenophytes (Eutreptiella spp.) and haptophyceans (Chrysochromulina spp.) in the western part and dinoflagellates (Dinophysis acuminata and D. rotundata), and small flagellates in the central part. The toxic cyanobacteria Nodularia has been observed only in small amounts in the northern parts of the Baltic Sea, but is very common in the southern areas.
In case the winds will be weak during the coming week, a small increase of Cyanobacteria surface blooms is to be expected in the Gulf of Finland and in the Archipelago Sea – Hanko peninsula area. Slight amounts of Cyanobacteria may also occur on the surface of the other sea areas.
Scientist Jan-Erik Bruun, SYKE Marine Centre, 'fistname.lastname@ymparisto.fi', tel. +358 405 662 890
See also:
Time series
Algae information service
