| Abstract | Atlantification of Arctic ocean is causing a sharp increase in temperature and salinity around Svalbard Islands and in Kongsfjorden. Such phenomenon and the input of sediment-rich glacial meltwater influence salinity, water column turbidity, and light penetration with ecological implications on the microbial features. With the aim to address the temporal variability of the microbial assemblage in relation to environmental variables, a 7-day study was carried out in Kongsfjorden, in late summer 2013. Abiotic (temperature, salinity, nutrients, total suspended matter, particulate inorganic, and organic carbon) and biotic (phyto -, picophyto-, bacterio-, and virioplankton abundance and microbial respiration) parameters were investigated at a station in the inner fjord area, ca. 8.5 km away from the glacier front. Phyto-, picophyto-, and virioplankton showed low abundance. Dinoflagellates and coccolithophorids dominated the phytoplankton community while Synechococcus sp. the picophytoplankton alone, in relation with Atlantic water. Low virus to bacteria ratios were detected, presumably linked to the high sedimentation rates. Interesting variability for picophytoplankton with depth, virioplankton with both time and depth, and respiratory rates with time were found. Moreover, the organic matter turnover was slower on the first sampling day compared to that of the following days. Planktonic abundance depended on the variability of both hydrology (seawater mass inflow) and freshwater runoff from the glacier (relative turbidity degree). Differently, the metabolic rates of respiration appeared to be linked with the particulate carbon pool. Over 1-week study, the diverse microbial dynamics appeared to be conditioned on complex forcing, emphasizing the importance of high-resolution experiment. |
| Text | 454316 2021 10.1007/s00300 020 02798 w Scopus 2 s2.0 85099903138 Short term dynamics Phytoplankton Bacterioplankton Virioplankton Microbial respiration Kongsfjorden Short term dynamics of nutrients, planktonic abundances, and microbial respiratory activity in the Arctic Kongsfjorden Svalbard, Norway Azzaro M.; Aliani S.; Maimone G.; Decembrini F.; Caroppo C.; Giglio F.; Langone L.; Miserocchi S.; Cosenza A.; Azzaro F.; Rappazzo A.C.; Cabral A.S.; Paranhos R.; Mancuso M.; La Ferla R. National Research Council, Institute of Polar Sciences, Spianata San Raineri, 98122 Messina, Italy; National Research Council, Institute of Marine Sciences, Forte Santa Teresa Pozzuolo Di Lerici, 19032 La Spezia, Italy; National Research Council, Institute of Water Research, Via Roma, 74121 Taranto, Italy; National Research Council, Institute of Polar Sciences, Via Gobetti, 40129 Bologna, Italy; National Research Council, Institute for Biological Resources and Marine Biotechnologies, Spianata San Raineri, 98122 Messina, Italy; Federal University of Rio de Janeiro, Instituto de Microbiologia Paulo de Goes, Av. Carlos Chagas Filho, 373, Rio de Janeiro, Brazil; Federal University of Rio de Janeiro, Institute of Biology, Av. Prof. Rodolpho Rocco 211, Rio de Janeiro, Brazil Atlantification of Arctic ocean is causing a sharp increase in temperature and salinity around Svalbard Islands and in Kongsfjorden. Such phenomenon and the input of sediment rich glacial meltwater influence salinity, water column turbidity, and light penetration with ecological implications on the microbial features. With the aim to address the temporal variability of the microbial assemblage in relation to environmental variables, a 7 day study was carried out in Kongsfjorden, in late summer 2013. Abiotic temperature, salinity, nutrients, total suspended matter, particulate inorganic, and organic carbon and biotic phyto , picophyto , bacterio , and virioplankton abundance and microbial respiration parameters were investigated at a station in the inner fjord area, ca. 8.5 km away from the glacier front. Phyto , picophyto , and virioplankton showed low abundance. Dinoflagellates and coccolithophorids dominated the phytoplankton community while Synechococcus sp. the picophytoplankton alone, in relation with Atlantic water. Low virus to bacteria ratios were detected, presumably linked to the high sedimentation rates. Interesting variability for picophytoplankton with depth, virioplankton with both time and depth, and respiratory rates with time were found. Moreover, the organic matter turnover was slower on the first sampling day compared to that of the following days. Planktonic abundance depended on the variability of both hydrology seawater mass inflow and freshwater runoff from the glacier relative turbidity degree . Differently, the metabolic rates of respiration appeared to be linked with the particulate carbon pool. Over 1 week study, the diverse microbial dynamics appeared to be conditioned on complex forcing, emphasizing the importance of high resolution experiment. 44 Published version http //www.scopus.com/record/display.url eid=2 s2.0 85099903138 origin=inward Short term dynamics of nutrients, planktonic abundances, and microbial respiratory activity in the Arctic Kongsfjorden Svalbard, Norway Polar Biology 2021_Short term Kongsfiorden.pdf Articolo in rivista Springer. 0722 4060 Polar biology Print Polar biology Print Polar biol. Print RAPPAZZO ALESSANDRO CIRO stefano.miserocchi MISEROCCHI STEFANO alessandro.cosenza COSENZA ALESSANDRO franco.decembrini DECEMBRINI FRANCO filippo.azzaro AZZARO FILIPPO carmela.caroppo CAROPPO CARMELA stefano.aliani ALIANI STEFANO maurizio.azzaro AZZARO MAURIZIO federico.giglio GIGLIO FEDERICO rosabruna.laferla LA FERLA ROSABRUNA leonardo.langone LANGONE LEONARDO giovanna.maimone MAIMONE GIOVANNA |
