Fig. 3

Phyla plot: Showing main Phyla in (A) biofilm samples and (B) sediment samples. Site abbreviations: BF = biofilm; Sed = sediment. STP: Sewage treatment plant; Out: Outflow pipe from the sewage treatment plant; JBSTP: sampled on rocks just below the sewage treatment plant outflow pipe; IT: intertidal; 100mE: 100 m east from the sewage treatment plant outflow pipe; 15mW: 15 m west from the sewage treatment plant outflow pipe; 15mWAn: anoxic sediment15m west from the sewage treatment plant outflow pipe; HC: Hangar Cove; BBL: Back Bay Lagoon Island (see Fig. 1 for map)