The Removal of Antibiotics in Relation to a Microbial Community in an Integrated Constructed Wetland for Tail Water Decontamination

Abstract

An integrated constructed wetland (ICW) with six subsystems has been operated for six years (60,000 Ton day−1) and exhibited strong stability and high efficiency for removing conventional pollutants in tail water. This study was aimed to characterize the removal efficiency of antibiotics in relation to bacterial community structure and composition in this integrated constructed wetland. Water samples were taken from different ICW sites in two distinct seasons (i.e. winter and summer). The results showed that concentrations of antibiotics in ICW decreased from influent to effluent with varying removal rates among the different antibiotics (quinolones, ulfonamides and macrolides). The pyrosequencing of 16S ribosomal DNA revealed that the composition of dominant phyla could be grouped into four bacterial clusters and the key discriminant phyla, family or genera from each cluster was strongly associated with the specific physicochemical parameters of water or type of antibiotics. Members of the key phyla (Proteobacteria, Bacteroidetes, Parcubacteria, and Actinobacteria) appeared to play an important role in antibiotics removal. In general, both the concentration of antibiotics and physicochemical parameters of water shaped the bacterial communities. These results improve our understanding of the interactions between antibiotics or water physiochemical parameters and bacterial communities in the integrated constructed wetland.