Cluster analysis of ciliates communities of eutrophic ponds in Saratov reservoir basin

Five distinct types of ciliates communities were resolved on the basis of cluster analysis of the data on ciliates community structure of 13 small water bodies and neighboring site of the Saratov reservoir. Communities with dominance of Tintinnidium fluviatile and other representatives of Choreotrichia (Spirotrichea) are characteristic for the reservoir and adjacent oxbow lakes. Characteristic species of ciliates communities of shallow ponds of Volga terrace and Zhiguli heights are representatives of subclass Oligotrichia (Strombidium spp.). High abundance of myxotrophic and heterotrophic species of Prostomatea and Olygohymenophorea is the main feature of deeper lakes of Zhiguli heights with an anaerobic summer hypolimnion. We discuss the possible relationships between the characteristics of resolved ciliate communities with environmental variables.