Figure 4.

Effect of sediment disturbance by fauna on electrogenic sulphur oxidation. Microprofiles of O₂ (red), ΣH₂S (blue) and pH (black and grey) are shown from sediment cores collected from the intertidal OSF. Different shades are used for replicate profiles for pH and ΣH₂S for image clarity, whereas a single median profile is shown for O₂. (a) Profiles from intact sediment cores. (b) Profiles from defaunated sediment cores. (c) Profiles from re-faunated sediment cores, in areas that were not visibly disrupted by mechanical disturbance caused by the re-introduced lugworms. (d) Profiles from re-faunated sediment cores, in areas that were not visibly disrupted by mechanical disturbance caused by the re-introduced lugworms.