Do benthic meiofaunal and macrofaunal communities respond to seasonality in pelagial processes in an Arctic fjord (Kongsfjorden, Spitsbergen)?

• Published in: Polar Biology
• Main Authors: Wlodarska-Kowalczuk, Maria, Górska, Barbara, Deja, Kajetan, Morata, Nathalie
• Other Authors: Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Akvaplan-Niva Tromsø, Norwegian Institute for Water Research (NIVA), ANR-10-LABX-0019,LabexMER,LabexMER Marine Excellence Research: a changing ocean(2010), ANR-11-PDOC-0018,ECOTAB,Effet des changements climatiques sur le benthos en Arctique(2011)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: ACL; Arctic fjords; barents sea; biomass; diversity; dynamic sedimentary environments; food bank; glacial fjord; macrobenthic fauna; macrofauna; Meiofauna; organic-matter; polar night; river estuary adventfjorden; Seasonality; shelf; Svalbard; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Adventfjorden; Barents Sea; Kongsfjord*; Kongsfjorden; Polar Biology; Spitsbergen
• Online Access: https://hal.science/hal-01483206; https://doi.org/10.1007/s00300-016-1982-2

WOS:000390030500014 International audience This study explores whether the marked seasonality in pelagic productivity and phytodetritus fluxes to the sea bottom in an Arctic fjord is reflected in variability of benthic communities in terms of taxonomic composition and standing stocks. Three stations located along the Kongsfjorden (west Spitsbergen) axis were visited in four seasons (May, August, October and January), and meiofauna and macrofauna was sampled. The elusive seasonal variability in benthic attributes contrasted with the clear seasonal effects in organic matter productivity and vertical fluxes (with diatom bloom-related peak in spring). No consistent differences in meiofaunal and macrofaunal density, diversity or composition among the four seasons were detected by PERMANOVA tests. Possible responses to spring food supply in meiofaunal reproduction timing were demonstrated in variability in individual size of Nematoda (decline in October after the maximum in August), Harpacticoida (decline in May and increase till October) and macrobenthic Crustacea (minimum in May). The spatial patterns shaped by the environmental gradients related to glacial inputs, the faunal impoverishment in inner basin and a shift in dominants along the fjord axis, were clearly designated and stable throughout the year. The resilience of Arctic fjordic benthic community to marked seasonality in pelagic phytodetritus fluxes may be related to organic matter reserves in sediments (large enough to sustain the detritus feeders on a year-round basis), inclusion of macroalgal carbon into the diet and common employment of lecithotrophic larva or direct development by polar benthos.