Ecology of testate amoebae (Protists) in Sphagnum peatlands of eastern Poland: Vertical micro-distribution and species assemblages in relation to environmental parameters

The testate amoebae communities living among different species of mosses in Sphagnum peatlands in eastern Poland were studied. Sampling was done on a monthly basis from April to November 2005–2007. To assess the importance of the vertical distribution of testate amoebae within the mosses, each sample was cut into two parts: the upper living part (1–5 cm) and the lower dead part (5–10 cm). The highest species richness occurred in hollows dominated by Sphagnum angustifolium, Sphagnum flexuosum and Sphagnum palustre. Lower numbers of taxa were observed in hummocks dominated by Sphagnum magellanicum, Polytrichum strictum and Polytrichum commune. There was a distinct horizontal micro-zonation of the abundance of testate amoebae occurring among Sphagnum mosses, but only a small difference ascertained among Polytrichum. The number of testate amoebae was significantly greater in the deeper samples. The results demonstrated that depth to water table, pH and total organic carbon can strongly regulate the abundance and taxonomic composition of testate amoebae.