FN Archimer Export Format PT J TI Shells of the bivalve Astarte moerchi give new evidence of a strong pelagic-benthic coupling shift occurring since the late 1970s in the North Water polynya BT AF OLIVIER, Frederic GAILLARD, Blandine THEBAULT, Julien MEZIANE, Tarik TREMBLAY, Rejean DUMONT, Dany BELANGER, Simon GOSSELIN, Michel JOLIVET, Aurelie CHAUVAUD, Laurent MARTEL, Andre L. RYSGAARD, Soren OLIVIER, Anne-Helene PETTRE, Julien MARS, Jerome GERBER, Silvain ARCHAMBAULT, Philippe AS 1:1,12;2:2;3:3;4:1;5:2;6:2;7:4;8:2;9:3,13;10:3;11:5;12:6,7,8;13:9;14:9;15:10;16:10;17:2,11; FF 1:;2:;3:;4:;5:;6:;7:;8:;9:;10:;11:;12:;13:;14:;15:;16:;17:; C1 Univ Antilles, Univ Caen Normandie, Sorbonne Univ,CNRS,Inst Rech Dev 207, Museum Natl Hist Nat,Lab Biol Organismes & Ecosys, CP53,61 Rue Buffon, F-75005 Paris, France. Univ Quebec Rimouski, Inst Sci Mer Rimouski, 310 Allee Ursulines, Rimouski, PQ G5L 3A1, Canada. Univ Bretagne Occidentale, Unite Mixte Rech Lab Sci Environm Marin LEMAR, UMR 6539, Inst Rech Dev,CNRS,Inst Univ Europeen Mer, Technopole Brest Iroise,Rue Dumont Urville, F-29280 Plouzane, France. Univ Quebec Rimouski, Dept Biol Chim & Geog, Quebec Oceans & BOREAS, 300 Allee Ursulines, Rimouski, PQ G5L 3A1, Canada. Canadian Museum Nat, Zool Sect Malacol, POB 3443,Stn D, Ottawa, ON K1P 6P4, Canada. Greenland Climate Res Ctr, Greenland Inst Nat Resources, Kivioq 2,POB 570, Nuuk 3900, Greenland. Univ Manitoba, CHR Fac Environm Earth & Resources, Ctr Earth Observat Sci, 499 Wallace Bldg, Winnipeg, MB R3T 2N2, Canada. Aarhus Univ, Arctic Res Ctr, CF Mollers Alle 8, DK-8000 Aarhus C, Denmark. Univ Rennes, M2S, IRISA, CNRS,Inria, F-35000 Rennes, France. CNRS, Grenoble INP, GIPSA Lab, Grenoble Alpes, F-38000 Grenoble, France. Univ Laval, Dept Biol, Quebec Oceans, Takuvik,Arcticnet, 1045 Ave Med, Laval, PQ G1V 0A6, Canada. MNHN, Stn Marine Concarneau, Pl Croix BP 225, F-29182 Concarneau, France. TBM Environm SOMME, 2 Rue Suede,Bloc 03, F-56000 Auray, France. C2 MNHN, FRANCE UNIV QUEBEC (UQAR-ISMER), CANADA UBO, FRANCE UNIV QUEBEC (UQAR), CANADA CANADIAN MUSEUM NAT, CANADA GREENLAND CLIMATE RES CTR, GREENLAND UNIV MANITOBA, CANADA UNIV AARHUS, DENMARK UNIV RENNES, FRANCE CNRS, FRANCE UNIV LAVAL, CANADA MNHN, FRANCE TBM ENVIRONM SOMME, FRANCE UM LEMAR IN WOS Cotutelle UMR copubli-france copubli-europe copubli-univ-france copubli-int-hors-europe IF 1.493 TC 13 UR https://archimer.ifremer.fr/doc/00686/79854/82695.pdf https://archimer.ifremer.fr/doc/00686/79854/82696.docx LA English DT Article DE ;Arctic;climate change;sclerochronology;pelagic-benthic coupling;match;mismatch hypothesis;bivalve growth AB Climate changes in the Arctic may weaken the currently tight pelagic-benthic coupling. In response to decreasing sea ice cover, arctic marine systems are expected to shift from a 'sea-ice algae-benthos' to a 'phytoplankton-zooplankton' dominance. We used mollusc shells as bioarchives and fatty acid trophic markers to estimate the effects of the reduction of sea ice cover on the food exported to the seafloor. Bathyal bivalve Astarte moerchi living at 600m depth in northern Baffin Bay reveals a clear shift in growth variations and Ba/Ca ratios since the late 1970s, which we relate to a change in food availability. Tissue fatty acid compositions show that this species feeds mainly on microalgae exported from the euphotic zone to the seabed. We, therefore, suggest that changes in pelagic-benthic coupling are likely due either to local changes in sea ice dynamics, mediated through bottom-up regulation exerted by sea ice on phytoplankton production, or to a mismatch between phytoplankton bloom and zooplankton grazing due to phenological change. Both possibilities allow a more regular and increased transfer of food to the seabed. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'. PY 2020 PD OCT SO Philosophical Transactions Of The Royal Society A-mathematical Physical And Engineering Sciences SN 1364-503X PU Royal Soc VL 378 IS 2181 UT 000567547600002 DI 10.1098/rsta.2019.0353 ID 79854 ER EF