The seasonal development of testate amoebae and ciliates was studied in two peatbogs with different pH values. The values of numbers of testate amoebae were seasonally changeable. The highest numbers of testate amoebae were found in spring and summer with the dominance of Areclla vulgaris, Nebela barbata and Cucurbitella sp. The density during the autumn was the lowest. The highest numbers of ciliate communities were noted in spring and autumn during the mass development of small Scuticociliatida and Colpodea. The density throughout the summer was the lowest. Generally, in the present studies the abundance of testate amoebae was correlated with the abundance of bacteria and heterotrophic flagellates. The density of bacterivorous Colpodea, Scuticociliatida and Cyrtophorida correlated positively with the density and biomass of bacteria. In low pH peatbog relations between microbial loop components were stronger.
Microzonation of testate amoebae and ciliates in relation to physical and chemical parameters in different species of mosses in peatland were studied. Regardless of the species of mosses, similar micro-vertical differentiation of these protozoa was ascertained. A similar number of species, like the abundance, significantly increased in the deepest sampling depth. The upper-most sampling of the mosses (0–5 cm) was dominated by mixotrophic taxons, whereas the deepest sampling level (5–10 cm) shown the increase of the proportion of bacterivore species. In peatlands the factors limiting the occurrence of ciliates and testate amoebae are physio-chemical suitablilty – mainly the total organic carbon content and water table depth, but with somewhat lower levels of pH and species of mosses.