Seasonal dynamic of diazotrophic activity and environmental variables affecting it in the Gulf of Riga, Baltic Sea.

ABSTRACT: The semi-enclosed Baltic Sea experiences regular summer blooms of diazotrophic cyanobacteria. Previously, it has been conclusively demonstrated that in open nitrogen-limited parts of the Baltic Sea, cyanobacteria successfully fix atmospheric N2. At the same time, diazotrophic activity is still poorly understood in Baltic Sea sub-regions where nitrogen and phosphorus are co-limiting primary production. To address this gap in research, we used the15 N tracer method for in situ incubations and measured the N2-fixation rate of heterocyst-forming cyanobacteria and picocyanobacteria in the Gulf of Riga, Baltic Sea, from April to September. Physicochemical variables and phytoplankton community composition were also determined. Our results show that the dominant species of cyanobacteria for this r

SUBMITTER: Liepina-Leimane I 

PROVIDER: S-EPMC9712029 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature