Source Community and Assembly Processes Affect the Efficiency of Microbial Microcystin Degradation on Drinking Water Filtration Membranes

Discussion Physical Properties of Lake and Stream Water Fed GDM Biofilms As observed previously, permeate flux in GDM systems stabilized after approximately 1 week of operation (Peter-Varbanets et al., 2010). Biomass addition led to twice as much hydraulic resistance and>3 times thicker biofilms (Figure 2A and Supplementary Figure S1), resulting in lower flux (McCarthy et al., 2002; Kohler et al., 2014; Silva et al., 2018). Permeate flux and biofilm thickness of the biomass-amended biofilms in ExpL and ExpS were similar, suggesting that their hydraulic properties were neither affected by the respective characteristics of the lake and stream water influx nor by the slight differences in setup. By contrast, the permeate flux of the two CTRL treatments was markedly different. It is conceivable that the three sedimentation tanks of ExpL allowed for higher particle removal than the single tank of ExpS (Figure 1). Also, the raw water for ExpL was pumped into the system from 5 m depth while it came from the surface of the stream for ExpS, which might have influenced the respective loads of inorganic particles and consequently flux (Chomiak et al., 2014). On the other hand, CTRL biofilms in ExpS were on average twice as thick as in ExpL (Supplementary Figure S1), but had higher and unstable flux rates (Figure 2A). This might be an indication for the activity of larger organisms (Supplementary Figure S1) feeding on the stream water biofilms (Derlon et al., 2012, 2013). Our short-te...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research