Emission of biogenic hydrogen sulfide

The principal processes by which H/sub 2/S has been believed to be generated on a global scale are (1) non-specific reduction of organic sulfur, and (2) from sulfate reduction by anaerobic bacteria. Our recent analyses indicate that dimethyl sulfide and dimethyldisulfide are the major compounds in the gaseous emissions from bacteria and fresh water green and blue-green algae isolated from different soil types and eutrophic as well as naturally clean waters. At the present time experimental data indicate that H/sub 2/S is not a major biogenic sulfide and is not the only natural occurring sulfur compound present as a volatile component in the circulation of sulfur through the biosphere. In both the algal and bacterial systems studied, the amount of H/sub 2/S produced was insignificant as compared to the organic sulfides measured.