Organic volatile sulfur in lakes ranging in sulfate and dissolved salt concentration over five orders of magnitude

• Main Authors: S. R. Richards, J. W. M. Rudd, C. A. Kelly, We Thank G. Brunskill, B. Last, M. Evans For Advice
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1994
• Subjects: Hofmann; Hudson; Hudson Bay
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.572.74; http://www.aslo.org/lo/toc/vol_39/issue_3/0562.pdf

Organic volatile sulfur compounds (VSCs) were studied in six hypersaline lakes (southern Saskatchewan) and in dilute wetland ponds (Hudson Bay Lowlands, HBL). [SOa2-] (0.0002-64 g liter-‘) and salt con-centration (0.003-370 g liter-‘) ranged over 5 orders of magnitude. Organic VSC concentrations in ponds and lakes with [SOd2-] < 7 g liter- ’ were similar to those measured previously in freshwater lakes. Lakes with>20gSO 42- liter-l, however, had VSC concentrations several orders of magnitude higher. Dimethyl sulfide (DMS) was the dominant species, reaching a concentration of 3,050 nM in one salt lake-the highest concentration yet recorded. Carbonyl sulfide (COS), methanethiol (MSH), dimethyl disulfide (DMDS), and carbon disulfide (CS,) were also detected. In the salt lakes, [DMS], [MSH], and [total VSC] were positively correlated (P < 0.05) to [SOa2-] but not to dissolved salt concentration (P < 0.05). The estimated mean atmospheric flux from the salt lakes ranged from 2 to 590 pmol S m-2 d-l. The low end of this range is similar to fluxes from Canadian Shield lakes and the ocean; the high end is 500 x higher. Fluxes from the HBL ponds (0.4-4 pmol S m-2 d-l) were similar to fluxes from Canadian Shield Biogenic sulfur gases are produced both chemically and biochemically in a variety of environments. Species such as dimethyl sul-fide (DMS) and carbonyl sulfide (COS) are of particular significance due to their roles in cli-mate modification (Hofmann 1990; Charlson