EMISSIONS OF SULFUR GASES FROM MARINE AND FRESH-WATER WETLANDS OF THEFLORIDA EVERGLADES - RATES AND EXTRAPOLATION USING REMOTE-SENSING

Rates of emissions of the biogenic sulfur (S) gases carbonyl sulfide ( COS), methyl mercaptan (MSH). dimethyl sulfide (DMS), and carbon disul fide (CS2) were measured in a variety of marine and freshwater wetland habitats in the Florida Everglades during a short duration period in October using dynamic chambers, cryotrapping techniques, and gas chrom atography. The most rapid emissions of >500 nmol m-2 h-1 occurred in r ed mangrove-dominated sites that were adjacent to open seawater and co ntained numerous crab burrows. Poorly drained red mangrove sites exhib ited lower fluxes of approximately 60 nmol m-2 h-1 which were similar to fluxes from the black mangrove areas which dominated the marine-inf luenced wetland sites in the Everglades. DMS was the dominant organo-S gas emitted especially in the freshwater areas. Spectral data from a scene from the Landsat thematic mapper were used to map habitats in th e Everglades. Six vegetation categories were delineated using geograph ical information system software and S gas emissions were extrapolated for the entire Everglades National Park. The black mangrove-dominated areas accounted for the largest portion of S gas emissions to the are a. The large area extent of the saw grass communities (42%) accounted for approximately 24% of the total S emissions.