| Abstrakt: |
Sulfur (S) constituents, microbial biomass, and sulfohydrolase activity were determined for each soil horizon at both hardwood and conifer sites in a Becket soil (Adirondack Mountains, New York). Drying of soil before analysis altered the S constituents. There was a threefold increase (p< 0.05) in sulfate in the organic horizons. Total S was greatest in the O horizons with 2,010 and 1,690 µg S/g in conifer and hardwood solums, respectively. Mineral soil had a maximum S concentration in the B21h horizon. Sulfate concentrations were a small proportion (<15%) of total S in B horizons. Organic S was dominant (93% of total S) in all horizons. Carbon‐bonded S and ester sulfate were 74 and 18% of total S, respectively. Microbial biomass was greatest in the 01 horizon of both hardwood and conifer solums (59 and 70 mg biomass C · 100 g−1dry mass, respectively). The B21h horizon contained the greatest biomass in the mineral soil. Sulfohydrolase activity exhibited the same distribution. Total S, carbon‐bonded S, and ester sulfate were all positively correlated (p< 0.05) to percent organic matter in the soil horizons. Correlations between microbial biomass and sulfohydrolase activity with organic S indicate the potential for microbial S transformations. Sulfate formation by mineralization may be more important than exogenous inputs. This has major implications for assessing the impact of atmospheric S deposition on soils. |
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