FN Archimer Export Format
PT J
TI Reorganization of a marine trophic network along an inshore-offshore gradient due to stronger pelagic-benthic coupling in coastal areas
BT 
AF KOPP, Dorothee
   LEFEBVRE, Sebastien
   CACHERA, Marie
   VILLANUEVA, Maria Ching
   ERNANDE, Bruno
AS 1:1,2,3;2:2;3:2,3;4:3;5:3;
FF 1:PDG-RBE-STH-LTBH;2:;3:PDG-RBE-HMMN-RHBL;4:PDG-RBE-STH-LBH;5:PDG-RBE-HMMN-RHBL;
C1 IFREMER, Unite Sci & Technol Halieut, Stn Lorient, F-56325 Lorient, France.
   Univ Lille 1, Lab Oceanol & Geosci, UMR CNRS LOG 8187, Stn Marine Wimereux, F-62930 Wimereux, France.
   IFREMER, Lab Ressources Halieut, F-62321 Boulogne Sur Mer, France.
C2 IFREMER, FRANCE
   UNIV LILLE, FRANCE
   IFREMER, FRANCE
SI LORIENT
   BOULOGNE
   BREST
SE PDG-RBE-STH-LTBH
   PDG-RBE-HMMN-RHBL
   PDG-RBE-STH-LBH
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
IF 3.512
TC 62
UR https://archimer.ifremer.fr/doc/00226/33765/32191.pdf
LA English
DT Article
CR CGFS2009
   COMOR 40
   IBTS 2010
BO Gwen Drez
   Thalia
   Thalassa
AB Recent theoretical considerations have highlighted the importance of the pelagic-benthic coupling in marine food webs. In continental shelf seas, it was hypothesized that the trophic network structure may change along an inshore-offshore gradient due to weakening of the pelagic-benthic coupling from coastal to offshore areas. We tested this assumption empirically using the eastern English Channel (EEC) as a case study. We sampled organisms from particulate organic matter to predatory fishes and used baseline-corrected carbon and nitrogen stable isotope ratios (δ13C and δ15N) to determine their trophic position. First, hierarchical clustering on δ13C and δ15N coupled to bootstrapping and estimates of the relative contribution of pelagic and benthic carbon sources to consumers’ diet showed that, at mesoscale, the EEC food web forms a continuum of four trophic levels with trophic groups spread across a pelagic and a benthic trophic pathway. Second, based on the same methods, a discrete approach examined changes in the local food web structure across three depth strata in order to investigate the inshore-offshore gradient. It showed stronger pelagic-benthic coupling in shallow coastal areas mostly due to a reorganization of the upper consumers relative to the two trophic pathways, benthic carbon sources being available to pelagic consumers and, reciprocally, pelagic sources becoming accessible to benthic species. Third a continuous approach examined changes in the mean and variance of upper consumers’ δ13C and δ15N with depth. It detected a significant decrease in δ13C variance and a significant increase in δ15N variance as depth increases. A theoretical two-source mixing model showed that an inshore-offshore decrease in the pelagic-benthic coupling was a sufficient condition to produce the δ13C variance pattern, thus supporting the conclusions of the discrete approach. These results suggest that environmental gradients such as the inshore-offshore one should be accounted for to better understand marine food webs dynamics.
PY 2015
PD JAN
SO Progress In Oceanography
SN 0079-6611
PU Pergamon-elsevier Science Ltd
VL 130
UT 000349059800011
BP 157
EP 171
DI 10.1016/j.pocean.2014.11.001
ID 33765
ER

EF