spacer
Woods Hole Oceanographic Institution

Elizabeth B. Kujawinski

spacer
Publications
»Using stable isotope probing to characterize differences between free-living and sediment-associated microorganisms in the subsurface.
»DOM in Lake Superior
»Deepwater Horizon hydrocarbons in the marine environment
»Microbes and marine DOM, Ann. Rev. Mar. Sci. 2011
»Greenland ice sheet outlet glacier: Insights from a new isotope-mixing model
»Groundwater DOM, GCA 2011
»Dispersants & DWH, ES&T 2011
»FT-MS variability in DOM, Org Geochem 2010
»Predatory Flavobacteria, FEMS Microb Ecol 2010
»Greenland Ice Sheet DOM, GCA 2010
»Protozoa and bacteria in aquifers, FEMS Microb Ecol, 2009
»Source markers in DOM, GCA 2009
»Automated data analysis, Anal. Chem. 2006
»Marine DOM and ESI FT-ICR MS; Marine Chem 2004
»DOM extraction by C18; Org. Geochem. 2003
»Black carbon by ESI FT-ICR MS; ES&T 2004
»ESI FT-ICR MS review; Env. Forensics 2002
»Marine protozoan surfactants; Marine Chem. 2002
»ESI MS and NOM; Org. Geochem. 2002
»ESI FT-ICR MS & humic acids; Anal. Chem. 2002
»Protozoan DOM & PCBs; ES&T 2001
»Protozoa & Fe, Th, C; Aquat. Microb. Ecol. 2001
»PCB uptake by protozoa; AEM 2000


spacer
M. P. Bhatia, S. B. Das, K. Longnecker, M. A. Charette, E. B. Kujawinski, Molecular characterization of dissolved organic matter associated with the Greenland Ice Sheet, Geochimica et Cosmochimica Acta 74: 3768-3784, 2010

Subsurface microbial oxidation of overridden soils and vegetation beneath glaciers and ice sheets may affect global carbon budgets on glacial-interglacial timescales. The likelihood and magnitude of this process depends on the chemical nature and reactivity of the subglacial organic carbon stores. We examined the composition of carbon pools associated with different regions of the Greenland ice sheet (subglacial, supraglacial, proglacial) in order to elucidate the type of dissolved organic matter (DOM) present in the subglacial discharge over a melt season. Electrospray ionization (ESI) Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry coupled to multivariate statistics permitted unprecedented molecular level characterization of this material and revealed that carbon pools associated with discrete glacial regions are comprised of different compound classes. Specifically, a larger proportion of protein-like compounds were observed in the supraglacial samples and in the early melt season (spring) subglacial discharge. In contrast, the late melt season (summer) subglacial discharge contained a greater fraction of lignin-like and other material presumably derived from underlying vegetation and soil. These results suggest (1) that the majority of supraglacial DOM originates from autochthonous microbial processes on the ice sheet surface, (2) that the subglacial DOM contains allochthonous carbon derived from overridden soils and vegetation as well as autochthonous carbon derived from in situ microbial metabolism, and (3) that the relative contribution of allochthonous and autochthonous material in subglacial discharge varies during the melt season. These conclusions are consistent with the hypothesis that, given sufficient time (e.g., overwinter storage), resident subglacial microbial communities may oxidize terrestrial material beneath the Greenland ice sheet. You can access the reprint at GCA here.

FILE » Text and figures


» Electronic Annex Table 1



© Woods Hole Oceanographic Institution
All rights reserved