Methane addition to an arctic lake in winter
Abstract
The possible usc of buried pipelines to transport natural gas (≃99% methane) through the Canadian arctic prompted us to study some of the dynamics of methane metabolism in an arctic lake at 63°38'N lat. The two basins of the lake were separated during winter 1977–1978 by a curtain and 300 kg of methane was dissolved into one side, to a maximum of 120 µM · liter−1 or 0.7 M· m−2. Oxidation occurred throughout the water column but the highest rates were at or nearthe sediment surface. High phosphate and nitrate additions did not stimulate oxidation. The sediments generated methane naturally and winter concentrations in undisturbed lakes were 0.2–1.0 µM·liter '. The added methane disappeared at a slow, steady rate of 1.89 mM · m−2· d−1 or 0.32 µM · liter 1· d−1 from February to June. The oxygen depletion rate of the entire experimental basin was 0.244 g· m−2· d−', compared with 0.210 in the control basin, and was not measurably affected by artificially added methane; a winter pipeline rupture would therefore probably not result in severe oxygen depletion in downstream lakes. These and other results were not expected based upon our knowledge of methane dynamics in temperate lakes.
- Publication:
-
Limnology and Oceanography
- Pub Date:
- January 1980
- DOI:
- 10.4319/lo.1980.25.1.0100
- Bibcode:
- 1980LimOc..25..100W