Figure 6.

(a) Effect of temperature and incubation time on the net carbon mineralization balance of sediment slurries (∼45 μM H₂). Net carbon mineralization balance was calculated by applying the standardizing factor in Table S1 (Supporting Information) to each specific rate, and then summing these. (b) Effect of temperature and incubation time on carbon dioxide concentrations measured from the slurry headspace (left vertical axis) and on the average carbon dioxide concentrations (open circles and right vertical axis). ^aAnnual average in situ temperature (Arrow indicates maximum average in situ temperature). ^bTemperature of maximum mineralization rate. ^cTemperature at which at least 50% of sulphate reduction was hydrogenotrophic. ^dFactor of increase of mineralization rate.