Seasonal patterns of testate amoebae and ciliates in three peatbogs: relationship to bacteria and flagellates (Poleski National Park, Eastern Poland)

The abundance and biomass of microbial communities has been assessed in three types of peatbogs, in order to test a hypothesis that the microbial communities (testate amoebae and ciliates) differed among peatbogs and that differences could be related to moisture conditions, water chemistry, bacterial and flagellate densities. The highest numbers of testate amoebae were found in spring and summer, however the highest numbers of ciliate communities were noted in spring and autumn. The relations demonstrated between bacteria, heterotrophic flagellates and protozoa may point to an important process of matter and energy flow from bacteria to higher trophic levels. In low pH peatbog, relations between microbial loop components were stronger. Consuming much of bacterial productions, protozoa become an important link between bacteria and micrometazoans. The studies showed that protozoa community is determined by pH and water level mainly in summer. In spring and autumn additional factors may be important. Probably conductivity, total organic carbon and concentration of appropriate food (bacteria and flagellates) are the major regulator of abundance and biomass of testate amoebae and ciliates.