Abstract
It has been established that conditions for the development of diatoms on a concrete embankment are favourable. Beside organisms permanently or periodically connected with the solid substrate, typical planktons also occurred. The following species were most numerous: Cymbella affinis, Nitzschia kützingiana, Amphora ovalis var. pediculus and Navicula gracilis. The most intensive development of diatoms was observed in April, May, July and October. The total number of organisms depended on pollution of water in the Żerań Canal, increased water temperature in autumn in the section between the Canal and Białobrzegi and intensity of waves.