FN Archimer Export Format
PT J
TI Influence of the mode of macrofauna-mediated bioturbation on the vertical distribution of living benthic foraminifera: First insight from axial tomodensitometry
BT 
AF BOUCHET, Vincent
   SAURIAU, Pierre-Guy
   DEBENAY, J.P.
   MERMILLOD-BLONDIN, F
   SCHMIDT, S
   AMIARD, J.C.
   DUPAS, B
AS 1:1,2;2:3;3:4;4:5;5:6;6:7;7:8;
FF 1:PDG-DOP-DCN-CRELA;2:;3:;4:;5:;6:;7:;
C1 IFREMER, CNRS, ELA, F-17137 Lhoumeau, France.
   Univ Angers, Lab BIAF, F-49045 Angers, France.
   Univ La Rochelle, CNRS, LIENSs, F-17000 La Rochelle, France.
   Ctr Noumea, IRD, F-98848 Noumea, Nouvelle Caledo, France.
   Univ Lyon 1, CNRS, UMR 5023, LEHF, F-69622 Villeurbanne, France.
   Univ Bordeaux 1, EPOC, CNRS, F-33405 Talence, France.
   Univ Nantes, SMAB, F-44322 Nantes 3, France.
   CHU Hotel Dieu, Serv Radiol, F-44000 Nantes, France.
C2 IFREMER, FRANCE
   UNIV ANGERS, FRANCE
   UNIV LA ROCHELLE, FRANCE
   IRD, FRANCE
   UNIV LYON, FRANCE
   UNIV BORDEAUX, FRANCE
   UNIV NANTES, FRANCE
   CHU NANTES, FRANCE
SI LA ROCHELLE
SE PDG-DOP-DCN-CRELA
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-p187
   copubli-univ-france
IF 2.116
TC 49
UR https://archimer.ifremer.fr/doc/2009/publication-6146.pdf
LA English
DT Article
DE ;Macrofauna;Living foraminifera;Interspecific interaction;CT scan;Bioturbating modes;Biogenic structures
AB We investigated the influence of bioturbation by macrofauna on the vertical distribution of living (stained) benthic foraminifera in marine intertidal sediments. We investigated the links between macrofaunal bioturbation and foraminiferal distribution, by sampling from stations situated on a gradient of perturbation by oyster-farming, which has a major effect on benthic faunal assemblages. Sediment cores were collected on the French Atlantic coast, from three intertidal stations: an oyster farm, an area without oysters but affected by oyster biodeposits, and a control station. Axial tomodensitometry (CT-scan) was used for three-dimensional visualization and two-dimensional analysis of the cores. Biogenic structure volumes were quantified and compared between cores. We collected the macrofauna, living foraminifera, shells and gravel from the cores after scanning, to validate image analysis. We did not investigate differences in the biogenic structure volume between cores. However, biogenic structure volume is not necessarily proportional to the extent of bioturbation in a core, given that many biodiffusive activities cannot be detected on CT-scans. Biodiffusors and larger gallery-diffusors were abundant in macrofaunal assemblage at the control station. By contrast, macrofaunal assemblages consisted principally of downward-conveyors at the two stations affected by oyster farming. At the control station, the vertical distribution of biogenic structures mainly built by the biodiffusor Scorbicularia plana and the large gallery-diffusor Hediste diversicolor was significantly correlated with the vertical profiles of living foraminifera in the sediment, whereas vertical distributions of foraminifera and downward-conveyors were not correlated at the station affected by oyster farming. This relationship was probably responsible for the collection of foraminifera in deep sediment layers (> 6 cm below the sediment surface) at the control station. As previously suggested for other species, oxygen diffusion may occur via the burrows built by S. plana and H. diversicolor, potentially increasing oxygen penetration and providing a favorable microhabitat for foraminifera in terms of oxygen levels. By contrast, the absence of living foraminifera below 6 cm at the stations affected by oyster farming was probably associated with a lack of biodiffusor and large gallery-diffusor bioturbation. Our findings suggest that the effect of macrofaunal bioturbation on the vertical distribution of foraminiferal assemblages in sediments depends on the effects of the macrofauna on bioirrigation and sediment oxidation, as deduced by Eh values, rather than on the biogenic structure volume produced by macrofauna. The loss of bioturbator functional diversity due to oyster farming may thus indirectly affect infaunal communities by suppressing favorable microhabitats produced by bioturbation.
PY 2009
PD MAR
SO Journal of Experimental Marine Biology and Ecology
SN 0022-0981
PU Elsevier
VL 371
IS 1
UT 000264557900003
BP 20
EP 33
DI 10.1016/j.jembe.2008.12.012
ID 6146
ER

EF