Comparison of Species Diversity of Microfauna in Biofilm Attached to Different Carriers

In order to explore the similarities and differences of the species diversity of microfauna in biofilm attached to different carriers, the variation of parameters related to microfauna on 3 types of carriers (multi-faceted hollow ball, K3 suspended filler and coke powder) and the correlations between diversity parameters of microfauna species and the performance of the reactors treating synthetic municipal wastewater were analyzed. Results indicatethat,57 species of microfauna are identified,including 7 species off lagellate,5 species of sarcodina,42species of ciliate and 3 kinds of metazoan; On the coke powder, the small flagellates are the dominant group. However, on multi-faceted hollow ball and K3 suspension filler, the small flagellates, free swimming ciliates and sessile ciliates alter nately become the dominant groups accompanying with the passage of time;The diversity index H of microfauna on suspended carriers varies with the shape of"M", while the H of the stacking carrier varies with the shape of "from-high-to low";The removal efficiencies of COD, NH₄⁺——N of the reactors filled with coke powder are (87±10)% and (92±6)%, respectively. The respective relationships of miniature animal diversity index (H), and richness index (R) with the removal efficiency of NH₄⁺——N are also positively correlated (P<0.01); There is a significant negative correlation between the dominance index λ and the removal efficiency of NH₄⁺——N (P<0.05); The species diversity index H of the population of microfauna in the biofilms decreases gradually, but the change rules of index H present different forms; Stalks ciliates are as NH₄⁺——N indicator microorganisms of coke powder.