Temporal dynamics of microbial communities from activated sludge in a municipal wastewater treatment plant

PEREZ MARÍA VICTORIA; ERIJMAN, LEONARDO; FIGUEROLA, EVA LM

Montreal

Congreso; 16th International Symposium on Microbial Ecology; 2016

International Society for Microbial Ecology

Better understanding of microbial community dynamics in activated sludge systems and its relationship with environmental and operational parameters is crucial to optimize the performance of wastewater treatment. Microbial communities of activated sludge samples were collected biweekly from a municipal wastewater treatment plant over a period of 3 years. Bacteria were analyzed using Illumina sequencing of 16S ribosomal RNA gene amplicons of the V3-V4 regions. Eukaryotic microorganisms were analyzed by microscopy observation in all fresh samples. The plant contained a core bacterial community of 90 abundant genus level operational taxonomic units ranging 10% to 64% of total reads(averaging 40%) across all samples. A canonical analysis of principal coordinates was applied to examine the influence of environmental and operational variables on microbial communities over time. Temperature showed a significant correlation (p=0.01), raising the possibility of a seasonal effect. Taxa-time relationship metric was applied to quantify the temporal dynamics exhibited by bacterial and eukaryotic communities. The taxa richness increased with time according to a power law model S=cTW, with exponents of w=0.20 for bacteria and w=0.17 for eukarya. The comparable rates of replacement, and the result of network interactions suggest that bacteria and eukaryotic microorganisms are similarly affected by the activated sludge environment.