Toggle Main Menu Toggle Search

Open Access padlockePrints

Emergent behaviour in a chlorophenol-mineralising three-tiered microbial `food web'

Lookup NU author(s): Dr Matthew WadeORCiD, Robert Pattinson, Professor Nick ParkerORCiD, Dr Jan DolfingORCiD



This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Anaerobic digestion enables the water industry to treat wastewater as a resource for generating energy and recovering valuable by-products. The complexity of the anaerobic digestion process has motivated the development of complex models. However, this complexity makes it intractable to pin-point stability and emergent behaviour. Here, the widely used Anaerobic Digestion Model No. 1 (ADM1) has been reduced to its very backbone, a syntrophic two-tiered microbial `food chain' and a slightly more complex three-tiered microbial `food web', with their stability analysed as function of the inowing substrate concentration and dilution rate. Parameterised for phenol and chlorophenol degradation, steady- states were always stable and non-oscillatory. Low input concentrations of chlorophenol were sufficient to maintain chlorophenol- and phenol-degrading populations but resulted in poor conversion and a hydrogen flux that was too low to sustain hydrogenotrophic methanogens. The addition of hydrogen and phenol boosted the populations of all three organisms, resulting in the counterintuitive phenomena that (i) the phenol degraders were stimulated by adding hydrogen, even though hydrogen inhibits phenol degradation, and (ii) the dechlorinators indirectly benefitted from measures that stimulated their hydrogenotrophic competitors; both phenomena hint at emergent behaviour.

Publication metadata

Author(s): Wade MJ, Pattinson RW, Parker NG, Dolfing J

Publication type: Article

Publication status: Published

Journal: Journal of Theoretical Biology

Year: 2016

Volume: 389

Pages: 171-186

Print publication date: 21/01/2016

Online publication date: 06/11/2015

Acceptance date: 22/10/2015

Date deposited: 23/11/2015

ISSN (print): 0022-5193

ISSN (electronic): 1095-8541

Publisher: Academic Press


DOI: 10.1016/j.jtbi.2015.10.032

PubMed id: 26551153


Altmetrics provided by Altmetric


Funder referenceFunder name
Institute of Sustainability, Newcastle University
BB/K003240/2Biotechnology and Biological Sciences Research Council UK