The Oxidation of Elemental Sulfur in Soil

Abstract

The effects of particle size, rate of application, soil pH, temperature, inoculation, and addition of organic matter on the oxidation of elemental S in soil were studied. In general the amount of S oxidized increased with decrease in particle size. Greatest oxidation occurred with particle sizes of < 100 mesh. Oxidation reached a peak at 60 days of incubation time. The amount of S applied to the soil did not seem to affect the fraction oxidized. Little S was oxidized at 4C, some at 10C. Temperatures of 30C and 40C were more effective than 23C and lower. Inoculation accelerated the oxidation. Organic matter increased the rate of oxidation when soil samples were inoculated but did not affect the process when soil samples were not inoculated. Decrease in soil pH was highly correlated with the amount of S oxidation.