A new paper has just been published in Environmental Microbiology, focussed on the export of microbial cells from the Greenland ice sheet (GrIS), and co-authored by Marek, Tyler, and Jakub. The research was a large collaboration between the Geological Survey of Denmark and Greenland and the Universities of Copenhagen, Bristol, and Prague, and part of our subglacial carbon project.
We monitored a river flowing out of a large outlet from the SW part of the ice sheet during the summer 2012 and measured the abundance, flux and community composition, and the factors affecting the community structure in the river water and suspended sediment. We estimate that ∼1021 cells were transported to the downstream fjord in 2012, equivalent to >30 Mg of organic carbon. Prokaryotic microbial assemblages were dominated by Proteobacteria, Bacteroidetes and Actinobacteria, and cell concentrations and community compositions were stable throughout the sample period. We argue that the subglacial environment is the primary source of the river-transported microbiota, and that cell export from the GrIS is dependent on discharge. We hypothesise that the release of subglacial microbiota to downstream ecosystems will increase as freshwater flux from the GrIS rises in a warming world.
Cameron KA, Stibal M, Hawkings JR, Mikkelsen AB, Telling J, Kohler TJ, Gözdereliler E, Zarsky JD, Wadham JL, Jacobsen CS (2016) Meltwater export of prokaryotic cells from the Greenland Ice Sheet. Environmental Microbiology, doi: 10.1111/1462-2920.13483