Sulfur constituents and cycling in waters, seston, and sediments of an oligotrophic lake

Organic and inorganic sulfur constituents in streams, the water column, seston, and sediments of an oligotrophic Adirondack lake were measured for 2 years (1981–1983). Soluble organic S constituents (C‐bonded S and ester sulfate) were 1–18% of total S in streams, the water column, and lake outlet. Seston S (0.3–1.2% dry mass) in South Lake consisted of ester sulfate (44–59%), C‐bonded S (32–43%), sulfate (10–16%), and nonsulfate inorganic S (<2%). Rates of S deposition measured in sediment traps were highest after spring turnover. The organic matter content (52– 81% dry mass) of traps at 5, 8, and 15.5 m showed no significant differences. Net mineralization of seston inputs was 26% based on mass balance calculations, with 43% of the ester sulfate input mineralized. Because most of the S input to the sediments was not mineralized, organic S accumulated and constituted the major (74% of total S) S component of the sediment.