| Abstract | Open fjords are subject to contrasting environmental conditions, owing to meltwater glacial inputs, terrestrial runoff, and marine water mass exchanges, which are exacerbated by anthropogenic and climate perturbations. Following a slope-dependent water circulation, the subtidal sandy sediment belt regulates the convergent transport of nutrients downward the fjord depths, and the effective entrapment of suspended particles and microorganisms. In this study, we aimed at testing how glacial and seawater inputs may influence the bacterial community structure of subtidal sand deposits in the Kongsfjorden. Through total and viable cell counting and an amplicon sequencing approach, we found relevant differences in bacterial community structure along the glacio-marine sampling transect. Viable and high nucleic acid content (HNA) cells represented an important fraction of the total community, generally decreasing toward the glacier front. Besides the predominance of Alpha- and Gammaproteobacteria, Bacteroidetes, Firmicutes and Parcubacteria, the bacterial community structure was likely affected by the glacial activity in the inner fjord, with the occurrence of distinctive phylotypes belonging to Gemmatimonadates, Nitrospirae, Acidobacteria, and Chloroflexi. Overall, our outcomes highlighted that exploring the bacterial community distribution and structure can provide new insights into the active role of sand deposits in coastal cold environments. |
| Authors | Conte, Antonella; Papale, Maria; Amalfitano, Stefano; Mikkonen, Anu; Rizzo, Carmen; Di Domenico, Emilio ; Michaud, Luigi ; Lo Giudice, Angelina |
| Text | 379532 2018 10.1016/j.scitotenv.2017.11.077 Scopus 2 s2.0 85034031443 ISI Web of Science WOS WOS 000424144200022 Coastal sands Glacial inputs Prokaryotic abundance Microbial community composition Ion PGM sequencing Bacterial community structure along the subtidal sandy sediment belt of a high Arctic fjord Kongsfjorden, Svalbard Islands Conte, Antonella; Papale, Maria; Amalfitano, Stefano; Mikkonen, Anu; Rizzo, Carmen; Di Domenico, Emilio ; Michaud, Luigi ; Lo Giudice, Angelina Department of Chemical Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, , Italy; Water Research Institute, National Research Council IRSA CNR , Monterotondo, Rome, , , Italy; Water Research Institute, National Research Council IRSA CNR , Monterotondo, Rome, , , Italy; Department of Biological and Environmental Sciences, University of Jyvaskyla, Jyvaskyla, , Finland; Institute for the Coastal Marine Environment, National Research Council IAMC CNR , Messina, , Italy Open fjords are subject to contrasting environmental conditions, owing to meltwater glacial inputs, terrestrial runoff, and marine water mass exchanges, which are exacerbated by anthropogenic and climate perturbations. Following a slope dependent water circulation, the subtidal sandy sediment belt regulates the convergent transport of nutrients downward the fjord depths, and the effective entrapment of suspended particles and microorganisms. In this study, we aimed at testing how glacial and seawater inputs may influence the bacterial community structure of subtidal sand deposits in the Kongsfjorden. Through total and viable cell counting and an amplicon sequencing approach, we found relevant differences in bacterial community structure along the glacio marine sampling transect. Viable and high nucleic acid content HNA cells represented an important fraction of the total community, generally decreasing toward the glacier front. Besides the predominance of Alpha and Gammaproteobacteria, Bacteroidetes, Firmicutes and Parcubacteria, the bacterial community structure was likely affected by the glacial activity in the inner fjord, with the occurrence of distinctive phylotypes belonging to Gemmatimonadates, Nitrospirae, Acidobacteria, and Chloroflexi. Overall, our outcomes highlighted that exploring the bacterial community distribution and structure can provide new insights into the active role of sand deposits in coastal cold environments. 619 620 Published version http //www.scopus.com/record/display.url eid=2 s2.0 85034031443 origin=inward Bacterial community structure along the subtidal sandy sediment belt of a high Arctic fjord Kongsfjorden, Svalbard Islands Versione pubblicata Conte_2018_STOTEN_Kongsfjorden.pdf Articolo in rivista Elsevier 0048 9697 Science of the total environment Science of the total environment Sci. total environ. stefano.amalfitano AMALFITANO STEFANO angelina.logiudice LO GIUDICE ANGELINA |
