Multidimensional Block Ordination Analysis of Relations betweenthe Communities of Hydrobionts in Saline Rivers
We present the results of a comprehensive study of five saline rivers in the arid region of Lake Elton, including hydrobiological surveys of plankton and benthic communities. For the statistical analysis of the associative links between the species structures of the macrozoobenthos, meiobenthos and zooplankton communities, the DIABLO method is used. This method combines multidimensional ordinations based on n blocks of observations and uses special algorithms of canonical correlation. It is shown that a significant proportion of the cumulative variation of the data can be explained by a consensus configuration based on information common to all three groups of observations. Using the cluster and Generalized Procrustes analysis, the diagrams are constructed and analyzed. All these makes it possible to isolate stable associations of taxa characteristic of particular biotopes with homogeneous environmental conditions. We have constructed graphs of correlation pleiades and calculated indicator significance for individual species of macrozoobenthos, meiobenthos and zooplankton. We have established that in the species composition of communities there is a high proportion of mixed but, on the genesis, “interpenetrating” ecological groups. Plankton and benthic communities correlate well enough with each other, which indicates a close relationship between them, due to both biotic interactions and a mutually agreed response to changes in aquatic environment factors. The results allow us to consider the plankton and bottom communities of highly mineralized rivers as non-equilibrium dynamically changing consortia of species.