Epipelic cyanobacteria and algae: a case study from Czech ponds

The present paper focuses on the epipelic cyanobacteria and algae (particularly desmids). Altogether 45 sediment samples were taken at ponds covering a pH/conductivity and trophic gradients. Statistic evaluation based on environmental variables measured, divided localities into four major groups differing also by sediment quality and its algal flora. Altogether 39 cyanobacterial species were found including sedimented planktic or litoral forms, with prevalence of motile filamentous genera (Komvophoron, Oscillatoria, Phormidium, Pseudanabaena). Although, the majority of 42 desmid taxa belongs to commonly occurring species with a wide ecological amplitude, several remarkable taxa occurred mostly at oligo/dystrophic sites with sandy sediments. The highest species richness of euglenophytes was found on the muddy sediments (both oxygenated and anoxic). Other epipelic organisms were represented by Gymnodinium aeruginosum, Paulinella chromatophora and various protozoa, feeding oil epipelic algae (Amoeba, Urceolus cyclostomus).