The role of microorganisms in transformations of sulphite in spruce forest soil

Transformations of sulphite and the participation of microorganisms were investigated in samples of fermentative (A₀₂) and humus (A₀₃) horizons from a spruce forest. About 80% of sulphite were almost immediately oxidized abiotically to sulphate, less than 1% persisted in the soil for several days and almost 20% were converted to a form not demonstrable as sulphite or sulphate. Microorganisms accelerated the disappearance of less than 10% of the added sulphite.