FIG. 6.

Sulfate reduction rates (a) and rates of methanogenesis (b) in slurry experiments with (□) and without (▪) molybdate addition. Slurries were made with 25 ml of diluted pond water and 5 ml of a pond water-sediment mixture (2:1), resulting in a final 18-fold dilution of the sample, and were incubated at room temperature on a shaking table. sulfate red., sulfate reduction; meth. prod., methane production.