Medium shapes the microbial community of water filters with implications for effluent quality

Vignola, M. , Werner, D., Wade, M. J., Meynet, P. and Davenport, R. J. (2018) Medium shapes the microbial community of water filters with implications for effluent quality. Water Research, 129, pp. 499-508. (doi: 10.1016/j.watres.2017.09.042) (PMID:29195186)

Abstract

Little is known about the forces that determine the assembly of diverse bacterial communities inhabiting drinking water treatment filters and how this affects drinking water quality. Two contrasting ecological theories can help to understand how natural microbial communities assemble; niche theory and neutral theory, where environmental deterministic factors or stochastic factors predominate respectively. This study investigates the development of the microbial community on two common contrasting filter materials (quartz sand and granular activated carbon-GAC), to elucidate the main factors governing their assembly, through the evaluation of environmental (i.e. filter medium type) and stochastic forces (random deaths, births and immigration). Laboratory-scale filter columns were used to mimic a rapid gravity filter; the microbiome of the filter materials, and of the filter influent and effluent, was characterised using next generation 16S rRNA gene amplicon sequencing and flow-cytometry. Chemical parameters (i.e. dissolved organic carbon, trihalomethanes formation) were also monitored to assess the final effluent quality. The filter communities seemed to be strongly assembled by selection rather than neutral processes, with only 28% of those OTUs shared with the source water detected on the filter medium following predictions using a neutral community model. GAC hosted a phylogenetically more diverse community than sand. The two filter media communities seeded the effluent water, triggering differences in both water quality and community composition of the effluents. Overall, GAC proved to be better than sand in controlling microbial growth, by promoting higher bacterial decay rates and hosting less bacterial cells, and showed better performance for putative pathogen control by leaking less Legionella cells into the effluent water.

• Item Type: Articles
• Additional Information: This study was supported by MERMAID, a Marie Skłodowska-Curie Initial Training Network [grant number 607492]. Russell Davenport would also like to acknowledge a Challenging Engineering award from the Engineering and Physical Sciences Research Council (EP/ I025782/1).
• Keywords: Drinking water quality, microbial ecology, neutral model, water filter.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Vignola, Dr Marta
• Authors: Vignola, M., Werner, D., Wade, M. J., Meynet, P., and Davenport, R. J.
• College/School: College of Science and Engineering > School of Engineering > Infrastructure and Environment
• Journal Name: Water Research
• Publisher: Elsevier
• ISSN: 0043-1354
• ISSN (Online): 1879-2448
• Published Online: 22 September 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Water Research 129: 499-508
• Publisher Policy: Reproduced under a Creative Commons License
• Data DOI: 10.17634/101925-1