Methane Distribution and Cycling in Tomales Bay, California
Sansone FJ, Rust TM, Smith SV. 1998. Methane Distribution and Cycling in Tomales Bay, California. Estuaries. 21(1):66-77
Cycling of methane (CH sub(4)) in Tomales Bay, a 28-km super(2) temperate estuary in northern California with relatively low inputs of organic carbon, was studied over a 1-yr period. Water column CH sub(4) concentrations showed spatial and temporal variability (range = 8-100 nM), and were supersaturated with respect to the atmosphere by a factor of 237. Rates of net water column CH sub(4) production-oxidation were determined by in situ experiments, and were not found to be significantly different from zero. Fluxes across the sediment-water interface, determined by direct measurement using benthic chambers, varied from -0.1 mu mol m super(-2) d super(-1) to +16 mu mol m super(-2) d super(-1) (positive fluxes into water). Methane concentrations in the two perennial creeks feeding the bay varied annually (140-950 nM); these creeks were a significant CH sub(4) source to the bay during winter. In addition, mass-balance calculations indicate a significant additional winter CH sub(4) source, which is hypothesized to result from storm-related runoff from dairy farms adjacent to the bay. Systemwide CH sub(4) budgets of the 16-km super(2) inner bay indicate benthic production (110 mol d super(-1)) and atmospheric evasion (110 mol d super(-1)) dominated during summer, while atmospheric evasion (160 mol d super(-1)) and runoff from dairy farms (90 mol d super(-1)) dominated during winter.
- Type
- Journal Article
- Authors
- Sansone, F; Rust, T; Smith, S
- Units
- PORE
- Keywords
- Agricultural runoff, Benthos, Biogeochemistry, Carbon, composition of water, Ecosystems, Energetics, energy flow, Estuaries, Eutrophication, Marine Environment, Methane, Methanogens, Multi-disciplinary Studies , Sediment-water exchanges, Tomales Bay, Water Analysis