Regulation of sulfate concentrations and methanogenesis in salt marsh soils

Gary M. King, University of Georgia
W. J. Wiebe, University of Georgia

Abstract

Controls of methanogenesis in soils of Sapelo Island, Georgia salt marshes have been investigated by altering water movement through soils of the tall Spartina alterniflora region (TS). Vertical water movement was shown to maintain the concentration of sulfate at levels near that of the tidal waters which flood the TS. Restriction of vertical water movement resulted in a decrease of interstitial sulfate concentration by a factor of 2-5 over a period of 2 months. This decrease in sulfate was accompanied by a marked increase in in vitro methane production. Sulfate depletion is postulated to occur in microzones within the soil; methane formation occurs subsequent to this depletion. In situ differences between methanogenesis in TS and SS regions are suggested to be the result of such depletion. © 1980 Academic Press Inc. (London) Limited.