Title Variability of the microbial community in the western Antarctic Peninsula from late fall to spring during a low ice cover year
Author Moreau, S.; Ferreyra, G.A.; Mercier, B.; Lemarchand, K.; Lionard, M.; Roy, S.; Msotajir, B.; Roy, S.; von Hardenberg, B.; Demers, S.
Author Affil Moreau, S., Université du Québec à a Rimouski, Institut des Sciences de la Mer de Rimouski (ISMER),, Rimouski, QC, Canada. Other: Aarhus University, Denmark; Instituto Antartico Argentico, Argentina; Department of Fisheries and Oceans, Institute of Ocean Sciences, Canada; Université de Montipellier II, France
Source Impacts of climate warming on polar marine and freshwater ecosystems, edited by S. Agustí, M.K. Sejr and C.M. Duarte. Polar Biology, 33(12), p.1599-1614. Publisher: Springer-Verlag, Berlin, Germany. ISSN: 0722- 4060
Publication Date Dec. 2010
Notes In English. 84 refs. GeoRef Acc. No: 308847. CRREL Acc. No: 65006244
Index Terms bacteria; ecology; geochemical cycles; ice; ice cover; solar radiation; ultraviolet radiation; Antarctica--Antarctic Peninsula; Southern Ocean; Antarctic Peninsula; Antarctica; carbon; carbon cycle; electromagnetic radiation; food chains; geochemical cycle; Melchior Archipelago; microorganisms; nutrients; productivity; sea ice
Abstract Although winter conditions play a major role in determining the productivity of the western Antarctic Peninsula (WAP) waters for the following spring and summer, a few studies have dealt with the seasonal variability of microorganisms in the WAP in winter. Moreover, because of regional warming, sea-ice retreat is happening earlier in spring, at the onset of the production season. In this context, this study describes the dynamics of the marine microbial community in the Melchior Archipelago (WAP) from fall to spring 2006. Samples were collected monthly to biweekly at four depths from the surface to the aphotic layer. The abundance and carbon content of bacteria, phytoplankton and microzooplankton were analyzed using flow cytometry and inverted microscopy, and bacterial richness was examined by PCR-DGGE. As expected, due to the extreme environmental conditions, the microbial community abundance and biomass were low in fall and winter. Bacterial abundance ranged from 1.2 to 2.8×105 cells ml- 1 showing a slight increase in spring. Phytoplankton biomass was low and dominated by small cells in fall and winter. Phytoplankton biomass increased in spring, and, despite potentially adequate growth conditions, this rise was small and phytoplankton was still dominated by small cells. In addition, the early disappearing of sea-ice in spring 2006 let the surface water exposed to ultraviolet B radiations, which seemed to have a negative impact on the microbial community in surface waters.
URL http://hdl.handle.net/10.1007/s00300-010-0806-z
Publication Type journal article
Record ID 91240