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Abstract Testate amoebae are unicellular organisms that occur worldwide in lacustrine habitats and have been widely used as proxies for palaeoreconstruction and bioindicators of contemporary ecosystems. Our knowledge of the environmental factors determining the spatial distribution of testate amoebae in stratified freshwater lakes remains limited. The objective of this study was to assess the correlations between studied environmental variables and spatial distribution and species structure of testate amoebae communities inhabiting different limnological zones within a single lake basin along the depth gradient. In our study, we used a multistation approach within one waterbody. We collected samples at five transects at five depths in four limnological zones, for a total of 69 samples from 24 sites. Redundancy and k‐means analysis distinguished four groups of samples associated with different environmental conditions. Our results indicate that the distribution of testate amoebae species was correlated with a variety of factors. Along the depth gradient, the distribution of communities was primarily correlated with temperature, electrical conductivity and blue–green algal phycoerythrin. Within the littoral zone, the distribution of species either correlated with the sand content in sediments or was determined by the stochastic beginning of community assembly. In deepwater habitats, the distribution of species was correlated with the dissolved oxygen concentration, pH and concentration of the blue–green algal phycoerythrin. We assume that bottom sediments in single stratified freshwater lakes in shallow and deep water zones represent two distinct biotopes for the formation of communities of testate amoebae, and assessing habitat and community differences in stratified lakes requires a multistation sampling approach.
Sysoev et al. (Fri,) studied this question.