Experimental Study on the Effect of the Physicochemical Properties of Contaminated Fillers in Bioretention System on Microbial Community Structure.

Six bioretention filter columns were designed to study the effects of the bioretention system on surface runoff reduction through rainfall simulation water distribution experiments, and the relationship between the physicochemical properties of contaminated fillers and microbial community structure was analyzed. Results show that (1) the water volume and load reduction effect of traditional bioretention soil media (BSM) + 5% water treatment residue (WTR) was better than that of traditional bioretention soil media; (2) soil moisture content (SMC), carbon, nitrogen, phosphorus, Cd, and Cu increased after the water distribution test, while the change of Zn in the filter columns varied; (3) species richness decreased after the experiment. In terms of microbial community structure, the top 10 dominant phyla did not change. At the genus level, Arthrobacter replaced Sphingomonas as the most abundant flora after the experiment; (4) the effects of the physicochemical properties of contaminated fillers on microbial community structure in terms of pH were not clear, but total organic carbon(TOC), total phosphorus(TP), and SMC greatly influenced the microbial community structure, while the influence of heavy metals on the relative abundance at the phylum and genus levels was not uniform. [ABSTRACT FROM AUTHOR]