Zooplankton assemblage concordance patterns in Brazilian reservoirs

The main goal of this study was to evaluate the assemblage concordance among three zooplankton groups (Rotifera, Cladocera and Copepoda) in 30 Brazilian reservoirs. According to Mantel tests and Procrustean analyses, there was a high level of assemblage concordance. Highest assemblage concordance was observed between cladocerans and copepods, while the lowest level of concordance was detected between copepods and rotifers. Based on environmental or biotic data, patterns of among-reservoir dissimilarities were fairly stable across the two seasonal periods analyzed in this study. Multiple Mantel tests were used to model the between-reservoir dissimilarities (Bray-Curtis distance) in zooplankton assemblage structure as a function of the limnological, geographical and morphological distances between pairs of reservoirs. The best predictor of faunistic dissimilarities was the matrix containing the limnological distances among the reservoirs. In general, these results are important for monitoring purposes because they supported the use of surrogate taxa and indicate that community concordance analysis may be a powerful tool for enhancing the efficiency of monitoring programs, ensuring their long-term sustainability.