FN Archimer Export Format
PT J
TI The vesicomyid bivalve habitat at cold seeps supports heterogeneous and dynamic macrofaunal assemblages
BT 
AF GUILLON, Erwan
   MENOT, Lenaick
   DECKER, Carole
   KRYLOVA, Elena
   OLU, Karine
AS 1:1;2:1;3:1;4:2;5:1;
FF 1:;2:PDG-REM-EEP-LEP;3:PDG-REM-EEP-LEP;4:;5:PDG-REM-EEP-LEP;
C1 IFREMER, Ctr Bretagne, REM EEP, Lab Environm Profond, F-29280 Plouzane, France.
   Russian Acad Sci, PP Shirshov Oceanol Inst, Nakhimovsky Prospekt 36, Moscow 117997, Russia.
C2 IFREMER, FRANCE
   PP SHIRSHOV OCEANOL INST, RUSSIA
SI BREST
SE PDG-REM-EEP-LEP
IN WOS Ifremer jusqu'en 2018
   copubli-int-hors-europe
IF 2.384
TC 22
UR https://archimer.ifremer.fr/doc/00361/47210/47165.pdf
LA English
DT Article
CR WACS
BO Pourquoi pas ?
DE ;Cold-seep;Macrofauna;Diversity;Dynamics;Vesicomyid clams;Gulf of Guinea
AB The high biodiversity found at cold seeps, despite elevated concentrations of methane and hydrogen sulfide, is attributed to multiple sources of habitat heterogeneity. In addition to geological and geochemical processes, biogenic habitats formed by large symbiont-bearing taxa, such as bivalves and siboglinid tubeworms, or by microbial mats drive the biodiversity of small-sized fauna. However, because these habitat-forming species also depend on geochemical gradients, the respective influence of abiotic and biotic factors in structuring associated macrofaunal communities is often unresolved. The giant pockmark Regab located at 3200 m depth on the Congo margin is characterized by different fluid-flow regimes, providing a mosaic of the most common biogenic habitats encountered at seeps: microbial mats, mussel beds, and vesicomyid clam beds; the latter being distributed along a gradient of environmental conditions from the center to the periphery of the pockmark. Here, we examined the structure of macrofaunal communities in biogenic habitats formed in soft sediment to (1) determine the influence of the habitats on the associated macrofaunal communities (inter-habitat comparison), (2) describe how macrofaunal communities vary among vesicomyid clam beds (intra-habitat comparison) and (3) assess the inter-annual variation in vesicomyid beds based on repeated sampling at a three-year interval. The highest densities were found in the microbial mat communities in intermediate fluid-flow areas, but they had low diversity — also observed in the sediment close to mussel beds. In contrast, vesicomyid beds harbored the highest diversity. The vesicomyid beds did not show a homogeneous macrofaunal community across sampled areas; instead, density and composition of macrofauna varied according to the location of the beds inside the pockmark. The clam bed sampled in the most active, central part of the pockmark resembled bacterial mat communities by the presence of highly sulfide-tolerant species living at the sediment surface, along with vesicomyid juveniles. This similarity suggests a gradual change in community composition from mats to clam beds. Inter-annual comparisons of the different clam beds highlighted that the most active central site had a more variable community than its peripheral counterparts. Finally, a rapid shift in community structure, particularly in polychaete families, in experimentally reduced oxygen concentrations in the central part of Regab, suggests that high beta-diversity communities can withstand intense variation in geochemical conditions. These community dynamics are likely related to the diversity and to the plasticity of the vesicomyids themselves, because they can cope with high spatial and temporal environmental variability at a very local scale.
PY 2017
PD FEB
SO Deep-sea Research Part I-oceanographic Research Papers
SN 0967-0637
PU Pergamon-elsevier Science Ltd
VL 120
UT 000394404100001
BP 1
EP 13
DI 10.1016/j.dsr.2016.12.008
ID 47210
ER

EF