Biogeochemistry and dissolved oxygen dynamics at a subglacial upwelling, Midtre Lovénbreen, Svalbard
Abstract:There is a growing awareness that biological processes affect solute acquisition in glacial meltwaters. An unprecedented, high-resolution record of dissolved oxygen (DO) in emergent subglacial meltwaters at polythermal Midtre Lovénbreen, Svalbard, is discussed in conjunction with the major-ion chemistry of periodic water samples within the catchment. The subglacial outburst increased solutes passing through the proglacial area and was coupled to a seasonal transition in upwelling character from suboxic waters to those with large diurnal fluctuations in the levels of DO saturation, latterly returning to sustained suboxic runoff. During the period of daily variation, DO correlated positively with discharge and inversely to total dissolved solute concentration. Consideration of SO4 2– concentrations showed they exceed those achievable with complete consumption of DO in saturated supraglacial meltwater, and dissolution experiments illustrated protracted abiotic sulphide oxidation remains an unlikely cause. Similarly, relatively elevated ratios of NO3 –/Cl– preclude denitrification aiding the catalysis of sulphide oxidation. Results here tentatively suggest sulphide oxidation is mediated by both aerobic and anoxic biochemical processes and that transition metals are the most likely oxidants. Bacteria are shown to impart a major control on the ionic composition of subglacial upwelling with variability in the ratio of oxygenated surface meltwaters and suboxic subglacial waters.
Document Type: Research Article
Publication date: 2010-12-01
- The Annals of Glaciology is a peer-reviewed, thematic journal published 2 to 4 times a year by the International Glaciological Society (IGS). Publication frequency is determined and volume/issue numbers assigned by the IGS Council on a year-to-year basis and with a lead time of 3 to 4 years. The Annals of Glaciology is included in the ISI Science Citation Index from volume 50, number 50 onwards.
Themes can be on any aspect of the study of snow and ice. Individual members can make a suggestion for a theme for an Annals issue to the Secretary General, who will forward it to the IGS Publications Committee. The IGS Publication Committee will make a recommendation for an individual themed Annals issue, together with a potential Annals Chief Editor for that issue, to IGS Council. The IGS Council will make the decision whether to proceed, taking into account the spread of topics and the overall capacity for publication of pages in Annals.
- Editorial Board
- Information for Authors
- Ingenta Connect is not responsible for the content or availability of external websites