Skip to main content
Article
Processes Controlling Carbon Cycling in Antarctic Glacier Surface Ecosystems
Geochemical Perspectives Letters
  • Elizabeth A. Bagshaw, Cardiff University
  • Martyn Tranter, University of Bristol
  • Jemma L. Wadham, University of Bristol
  • Andrew G. Fountain, Portland State University
  • A. Dubnick, University of Alberta
  • S. Fitzsimons, University of Otago
Document Type
Article
Publication Date
1-21-2016
Subjects
  • Cryoconite,
  • Carbon cycle (Biogeochemistry)
Abstract

Glacier surface ecosystems, including cryoconite holes and cryolakes, are significant contributors to regional carbon cycles. Incubation experiments to determine the net production (NEP) of organic matter in cryoconite typically have durations of 6-24 hours, and produce a wide range of results, many of which indicate that the system is net heterotrophic. We employ longer term incubations to examine the temporal variation of NEP in cryoconite from the McMurdo Dry Valleys, Antarctica to examine the effect of sediment disturbance on system production, and to understand processes controlling production over the lifetimes of glacier surface ecosystems. The shorter-term incubations have durations of one week and show net heterotrophy. The longer term incubations of approximately one year show net autotrophy, but only after a period of about 40 days (~1000 hours). The control on net organic carbon production is a combination of the rate of diffusion of dissolved inorganic carbon from heterotrophic activity within cryoconite into the water, the rate of carbonate dissolution, and the saturation of carbonate in the water (which is a result of photosynthesis in a closed system). We demonstrate that sediment on glacier surfaces has the potential to accumulate carbon over timescales of months to years.

DOI
10.7185/geochemlet.1605
Persistent Identifier
http://archives.pdx.edu/ds/psu/16680
Citation Information
Bagshaw, E.A., Tranter, M., Wadham, J.L., Fountain, A.G., Dubnick, A., Fitzsimons, S. (2016) Processes controlling carbon cycling in Antarctic glacier surface ecosystems. Geochem. Persp. Let. 2, 44-54.