Glacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard)

Handle URI:
http://hdl.handle.net/10754/622297
Title:
Glacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard)
Authors:
Bourgeois, Solveig; Kerhervé, Philippe; Calleja, Maria Ll; Many, Gaël; Morata, Nathalie
Abstract:
With climate change, the strong seasonality and tight pelagic-benthic coupling in the Arctic is expected to change in the next few decades. It is currently unclear how the benthos will be affected by changes of environmental conditions such as supplies of organic matter (OM) from the water column. In the last decade, Kongsfjorden (79°N), a high Arctic fjord in Svalbard influenced by several glaciers and Atlantic water inflow, has been a site of great interest owing to its high sensitivity to climate change, evidenced by a reduction in ice cover and an increase in melting freshwater. To investigate how spatial and seasonal changes in vertical fluxes can impact the benthic compartment of Kongsfjorden, we studied the organic matter characteristics (in terms of quantity and quality) and prokaryotic distribution in sediments from 3 stations along a transect extending from the glacier into the outer fjord in 4 different seasons (spring, summer, autumn and winter) in 2012–2013. The biochemical parameters used to describe the sedimentary organic matter were organic carbon (OC), total nitrogen, bulk stable isotope ratios, pigments (chorophyll-a and phaeopigments) and biopolymeric carbon (BPC), which is the sum of the main macromolecules, i.e. lipids, proteins and carbohydrates. Prokaryotic abundance and distribution were estimated by 4′,6-diamidino-2-phenylindole (DAPI) staining. This study identifies a well-marked quantitative gradient of biogenic compounds throughout all seasons and also highlights a discrepancy between the quantity and quality of sedimentary organic matter within the fjord. The sediments near the glacier were organic-poor (< 0.3%OC), however the high primary productivity in the water column displayed during spring was reflected in summer sediments, and exhibited higher freshness of material at the inner station compared to the outer basin (means C-chlorophyll-a/OC ~ 5 and 1.5%, respectively). However, sediments at the glacier front were depleted in BPC (~ 0.2–0.3 mg C g DW) by 4.5 and 9 times compared to sediments from the inner and outer stations. δC values in sedimentary organic matter of Kongsfjorden varied between − 23.8 and − 19.3‰ and reflected distinct sources of organic matter between basins. Bacterial total cell numbers in sediments of Kongsfjorden were < 2 × 10 cells ml and the prokaryotic community structure was strongly influenced by the marked environmental biogenic gradients. Overall, the spatial variability prevailed over the seasonal variability in sediments of Kongsfjorden suggesting that glacier inputs prominently control the functioning of this benthic ecosystem and its communities. Regional index terms: Norway, Svalbard, Kongsfjorden.
KAUST Department:
Red Sea Research Center (RSRC)
Citation:
Bourgeois S, Kerhervé P, Calleja ML, Many G, Morata N (2016) Glacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard). Journal of Marine Systems 164: 112–127. Available: http://dx.doi.org/10.1016/j.jmarsys.2016.08.009.
Publisher:
Elsevier BV
Journal:
Journal of Marine Systems
Issue Date:
23-Aug-2016
DOI:
10.1016/j.jmarsys.2016.08.009
Type:
Article
ISSN:
0924-7963
Sponsors:
European Social Fund; Institut Polaire Français Paul Emile Victor; Agence Nationale de la Recherche[ANR-11-PDOC-0018]; AWIPEV; French General Council of Finistère[CG29]; Spanish Research Council[JAEDOC030-2010]
Appears in Collections:
Articles; Red Sea Research Center (RSRC)

Full metadata record

DC FieldValue Language
dc.contributor.authorBourgeois, Solveigen
dc.contributor.authorKerhervé, Philippeen
dc.contributor.authorCalleja, Maria Llen
dc.contributor.authorMany, Gaëlen
dc.contributor.authorMorata, Nathalieen
dc.date.accessioned2017-01-02T09:08:24Z-
dc.date.available2017-01-02T09:08:24Z-
dc.date.issued2016-08-23en
dc.identifier.citationBourgeois S, Kerhervé P, Calleja ML, Many G, Morata N (2016) Glacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard). Journal of Marine Systems 164: 112–127. Available: http://dx.doi.org/10.1016/j.jmarsys.2016.08.009.en
dc.identifier.issn0924-7963en
dc.identifier.doi10.1016/j.jmarsys.2016.08.009en
dc.identifier.urihttp://hdl.handle.net/10754/622297-
dc.description.abstractWith climate change, the strong seasonality and tight pelagic-benthic coupling in the Arctic is expected to change in the next few decades. It is currently unclear how the benthos will be affected by changes of environmental conditions such as supplies of organic matter (OM) from the water column. In the last decade, Kongsfjorden (79°N), a high Arctic fjord in Svalbard influenced by several glaciers and Atlantic water inflow, has been a site of great interest owing to its high sensitivity to climate change, evidenced by a reduction in ice cover and an increase in melting freshwater. To investigate how spatial and seasonal changes in vertical fluxes can impact the benthic compartment of Kongsfjorden, we studied the organic matter characteristics (in terms of quantity and quality) and prokaryotic distribution in sediments from 3 stations along a transect extending from the glacier into the outer fjord in 4 different seasons (spring, summer, autumn and winter) in 2012–2013. The biochemical parameters used to describe the sedimentary organic matter were organic carbon (OC), total nitrogen, bulk stable isotope ratios, pigments (chorophyll-a and phaeopigments) and biopolymeric carbon (BPC), which is the sum of the main macromolecules, i.e. lipids, proteins and carbohydrates. Prokaryotic abundance and distribution were estimated by 4′,6-diamidino-2-phenylindole (DAPI) staining. This study identifies a well-marked quantitative gradient of biogenic compounds throughout all seasons and also highlights a discrepancy between the quantity and quality of sedimentary organic matter within the fjord. The sediments near the glacier were organic-poor (< 0.3%OC), however the high primary productivity in the water column displayed during spring was reflected in summer sediments, and exhibited higher freshness of material at the inner station compared to the outer basin (means C-chlorophyll-a/OC ~ 5 and 1.5%, respectively). However, sediments at the glacier front were depleted in BPC (~ 0.2–0.3 mg C g DW) by 4.5 and 9 times compared to sediments from the inner and outer stations. δC values in sedimentary organic matter of Kongsfjorden varied between − 23.8 and − 19.3‰ and reflected distinct sources of organic matter between basins. Bacterial total cell numbers in sediments of Kongsfjorden were < 2 × 10 cells ml and the prokaryotic community structure was strongly influenced by the marked environmental biogenic gradients. Overall, the spatial variability prevailed over the seasonal variability in sediments of Kongsfjorden suggesting that glacier inputs prominently control the functioning of this benthic ecosystem and its communities. Regional index terms: Norway, Svalbard, Kongsfjorden.en
dc.description.sponsorshipEuropean Social Funden
dc.description.sponsorshipInstitut Polaire Français Paul Emile Victoren
dc.description.sponsorshipAgence Nationale de la Recherche[ANR-11-PDOC-0018]en
dc.description.sponsorshipAWIPEVen
dc.description.sponsorshipFrench General Council of Finistère[CG29]en
dc.description.sponsorshipSpanish Research Council[JAEDOC030-2010]en
dc.publisherElsevier BVen
dc.subjectBacteriaen
dc.subjectBiomarkersen
dc.subjectBiopolymeric carbonen
dc.subjectClimate changeen
dc.subjectPigmentsen
dc.subjectPolar zonesen
dc.titleGlacier inputs influence organic matter composition and prokaryotic distribution in a high Arctic fjord (Kongsfjorden, Svalbard)en
dc.typeArticleen
dc.contributor.departmentRed Sea Research Center (RSRC)en
dc.identifier.journalJournal of Marine Systemsen
dc.contributor.institutionLaboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539, CNRS-IRD-UBO-Ifremer, IUEM, Rue Dumont d'Urville, Plouzané, 29280, Franceen
dc.contributor.institutionOceanlab, School of Biological Sciences, University of Aberdeen, Newburgh, AB41 6AA, United Kingdomen
dc.contributor.institutionCNRS, CEntre de Formation et de Recherche sur les Environnements Méditerranéens (CEFREM), UMR 5110, Perpignan, F-66860, Franceen
dc.contributor.institutionUniv. Perpignan Via Domitia, CEntre de Formation et de Recherche sur les Environnements Méditerranéens (CEFREM), UMR 5110, Perpignan, F-66860, Franceen
dc.contributor.institutionConsejo Superior de Investigaciones Científicas (CSIC), Instituto ANdaluz de Ciencias de la Tierra (IACT), Avenida de Las Palmeras 4, Granada, 18100, Spainen
dc.contributor.institutionAkvaplan-niva, Fram Centre for Climate and the Environment, Tromsø, 9296, Norwayen
kaust.authorCalleja, Maria Llen
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