In order to understand the variability of diatoms in coastal lakes and its relationship to salinity, the authors have conducted a two-year study at Lake Resko Przymorskie (the Southern Baltic coast), which has a salinity between 1.9-4.8 PSU. Redundancy analysis (RDA) was used to describe the relationship between the species composition and selected variables. Four of the 10 measured variables of surface water chemistry (Cl- and PO43- concentrations, temperature, and pH) significantly explained 23% of the variation in the diatom species composition.
We found 82 taxa of diatoms (mostly tychoplanktonic) and determined the optimum and tolerance levels of salinity for predominant taxa (49 species with minimum 2% abundance). The optimum chloride concentration for the predominant diatoms ranged from 1471 to 2961 mg Cl- l-1.
The most abundant brackish water species was