EN
The diatoms communities of Trzcianka Stream were characterized by high species diversity. The research carried out in 2009–2010 made possible to indicate 158 taxa of diatoms, mainly the most numerous Navicula gregaria, N. lanceolata, Planothidium lanceolatum, Amphora pediculus and Surirella minuta – a cosmopolitan species, frequent in different types of water reservoir with low level of the electrolytic conductivity. The alkaliphilous (pH>7) and the eutraphentic diatoms, which are usually characteristic for fertile water ecosystems, were dominated in each researched station.