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22. Carbon emission associated with respiration and calcification of nine gastropod species from the intertidal rocky shore of Western Europe

Author

Tagliarolo, Morgana, Clavier, Jacques, Chauvaud, Laurent, and Grall, Jacques

Subjects
Calcification (Physiology) -- Causes of, Gastropods -- Physiological aspects, Carbon dioxide -- Physiological aspects, Intertidal areas -- Environmental aspects, Biological sciences
Abstract

Intertidal rocky shores are characterized by vertical zonation that results from the interplay between environmental conditions, organism physiology, and species interactions. Metabolism of intertidal organisms is highly variable between species [...]

Published
2013
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35. Seasonal and diurnal variability in carbon respiration, calcification and excretion rates of the abalone Haliotis tuberculata L.

Author

Chapperon, Coraline, Clavier, Jacques, Dugué, Clément, Amice, Erwan, Le Goff, Marion, Roussel, Sabine, Chapperon, Coraline, Clavier, Jacques, Dugué, Clément, Amice, Erwan, Le Goff, Marion, and Roussel, Sabine

Abstract

Abalone (Haliotis spp.) are commercially important marine shellfish species worldwide. Knowledge about the physiology of abalone that impacts life-history traits is important for a better understanding of the biology of the species and the impact of stressful husbandry procedures at different seasons. The present study quantified the seasonal and diurnal variations in four physiological parameters of the European species Haliotis tuberculata, i.e. carbon aerial and aquatic respiration, calcification and excretion rates, and the effect of prolonged aerial exposure upon abalone aerial respiration. We also investigated the effect of individual size upon these physiological parameters. Aquatic respiration and calcification rates showed an allometric relationship with biomass. All parameters showed lower rates in cool season and higher rates in warmer season. Temperature was assumed to be the primary driver of the reported seasonal variability in physiological parameters, although reproductive needs and nutrition may also contribute to the observed patterns. Importantly, abalone did not stop calcifying in winter, and calcified more at night than during the day. Abalone did not respire more underwater at night-time than at daytime, however they excreted more overnight. The low air:aquatic ratio (0.2) is likely to be an energy-saving strategy for emerged H. tuberculata individuals. This study highlights the temporal heterogeneity in physiological rates of H. tuberculata, which constitutes a species

Published
2019
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39. Variability in diel and seasonal in situ metabolism of the tropical gastropod tectus niloticus L, in the south-west lagoon of New Caledonia

Author

Lorrain, Anne, Clavier, Jacques, Thébault, Julien, Tremblay-Boyer, L, Houlbrèque, F, Amice, E, Le Goff, M, Chauvaud, Laurent, 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 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), Institut de Recherche pour le Développement (IRD), University of British Columbia (UBC), Biocomplexité des écosystèmes coralliens de l'Indo-Pacifique (CoReUS2), and 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)

Subjects
Size, New Caledonia, [SDU]Sciences of the Universe [physics], ACL, Carbon fluxes, CO2, Seasonal variations, CaCO3, Diel variations, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Gastropod
Abstract

International audience; Researchers often use metabolic measurements in the field over narrow time periods to estimate an organism's metabolism over large time scales. Here, we measured in situ respiration, calcification and excretion rates of the tropical gastropod Tectus niloticus L. through benthic chamber experiments. Our samples spanned a 21 h time frame and were taken during both the warm and cool seasons. We assessed diel and seasonal variability in metabolic rates, as well as the effect of individual size and the contribution of shell epi-and endobionts. Our results show that metabolic rates vary through time at both diel and seasonal scales, as measured fluxes for respiration and calcification were significantly higher at night during the warm season. This nocturnal pattern was not significant in the cool season. Size effects were significant with higher respiration and calcification rates for small individuals regardless of the season, although the difference tended to be more pronounced in the warm season. We also found that shell epi-and endobionts made an important contribution to respiration, as 40 and up to 100% of total measured fluxes for night and day, respectively, could be attributed to the shell community. More importantly, the direction of the measured flux was occasionally opposite that of the individual trochus, highlighting that the contribution of shell epi-and endobionts must be accounted for in order to achieve an accurate understanding of individual metabolism. Lastly, depending on the time of day and season when measurements are taken, ignoring diel or seasonal variations in metabolic rates could result in important under-or overestimation of the contributions of gastropods to carbon and calcium carbonate fluxes in coastal ecosystems.

Published
2015
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40. Acoustic behaviours of large crustaceans in NE Atlantic coastal habitats

Author

Coquereau, Laura, Grall, Jacques, Clavier, Jacques, Jolivet, Aurelie, Chauvaud, Laurent, Coquereau, Laura, Grall, Jacques, Clavier, Jacques, Jolivet, Aurelie, and Chauvaud, Laurent

Abstract

Although many studies have investigated the benthic environment of temperate marine waters, little is known about the acoustic behaviour of the organisms in these habitats, particularly crustaceans. This study focused on the acoustic behaviour of large crustaceans in NE Atlantic coastal regions. A total of 11 crustacean species were recorded in tank-based experiments to identify sound-producing species and the behaviours associated with their sounds as well as to quantitatively characterise and compare the sounds. A total of 34 sounds were associated with behaviours such as moving, feeding, mandible rubbing, swimming, species-specific behaviour and other unidentified behaviours. The sounds included single pulse and pulse train signals that were distributed across a peak frequency spectrum of 3 to 45 kHz with received levels between 93 and 142 dB re 1 mu Pa (peak to peak). The results demonstrated that Brachyura had the most diverse sound types. Using a combination of several acoustic features, 24% of the recorded sounds appeared to have a high potential to be differentiated in field recordings: the feeding sound of Cancer pagurus, Carcinus maenas, Necora puber and Pachygrapsus marmoratus; the species-specific sound of C. pagurus and Galathea squamifera; and the pulse train sound associated with unidentified behaviours of Lophozozymus incisus and N. puber. These findings extend the existing crustacean acoustic library in marine ecosystems and contribute to our understanding of in situ acoustic recordings in temperate regions.

Published
2016
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41. Responses of Two Scleractinian Corals to Cobalt Pollution and Ocean Acidification

Author

Biscere, Tom, Rodolfo-metalpa, Riccardo, Lorrain, Anne, Chauvaud, Laurent, Thebault, Julien, Clavier, Jacques, Houlbreque, Fanny, Biscere, Tom, Rodolfo-metalpa, Riccardo, Lorrain, Anne, Chauvaud, Laurent, Thebault, Julien, Clavier, Jacques, and Houlbreque, Fanny

Abstract

The effects of ocean acidification alone or in combination with warming on coral metabolism have been extensively investigated, whereas none of these studies consider that most coral reefs near shore are already impacted by other natural anthropogenic inputs such as metal pollution. It is likely that projected ocean acidification levels will aggravate coral reef health. We first investigated how ocean acidification interacts with one near shore locally abundant metal on the physiology of two major reef-building corals: Stylophora pistillata and Acropora muricata. Two pH levels (pH(T) 8.02; pCO(2) 366 mu atm and pH(T) 7.75; pCO(2) 1140 mu atm) and two cobalt concentrations (natural, 0.03 mu g L-1 and polluted, 0.2 mu g L-1) were tested during five weeks in aquaria. We found that, for both species, cobalt input decreased significantly their growth rates by 28% while it stimulated their photosystem II, with higher values of rETR(max) (relative Electron Transport Rate). Elevated pCO(2) levels acted differently on the coral rETR(max) values and did not affect their growth rates. No consistent interaction was found between pCO(2) levels and cobalt concentrations. We also measured in situ the effect of higher cobalt concentrations (1.06 +/- 0.16 mu g L-1) on A. muricata using benthic chamber experiments. At this elevated concentration, cobalt decreased simultaneously coral growth and photosynthetic rates, indicating that the toxic threshold for this pollutant has been reached for both host cells and zooxanthellae. Our results from both aquaria and in situ experiments, suggest that these coral species are not particularly sensitive to high pCO(2) conditions but they are to ecologically relevant cobalt concentrations. Our study reveals that some reefs may be yet subjected to deleterious pollution levels, and even if no interaction between pCO(2) levels and cobalt concentration has been found, it is likely that coral metabolism will be weakened if they are subjected to additi

Published
2015
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43. Low community photosynthetic quotient in coral reef sediments Un quotient photosynthétique des communautés faible dans les sédiments de récif corallien

Author

Taddei, Dorothée, Cuet, Pascale, Patrick, Frouin, Esbelin, Clémentine, Clavier, Jacques, Laboratoire d'Ecologie Marine (ECOMAR), Université de La Réunion (UR), 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), and 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 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)

Subjects
Oxygen, Community respiratory quotient, [SDE]Environmental Sciences, Sediment, Reunion island, Coral reef, Carbon, Community photosynthetic quotient
Abstract

International audience; Fluxes of dissolved inorganic carbon and oxygen at the water-sediment interface were measured at eight coral reef stations (Indian Ocean) in summer and winter. The dark fluxes provided the community respiratory quotient (CRQ = dissolved inorganic carbon release / oxygen uptake) and the diurnal fluxes corrected from the dark fluxes gave the community photosynthetic quotient (CPQ = oxygen gross release / dissolved inorganic carbon gross uptake). The CRQ and the winter CPQ were not significantly different from 1. Summer CPQ (0.79; SD 0.02) was significantly lower than 1 due to the combined effect of the daily evolution of the community respiration and the discrepancy between the daily evolution in community oxygen respiration and community carbon respiration. These results highlight the importance of measuring simultaneously the benthic community production and respiration for long term integrated data sets, instead of the traditional daily or seasonal budget calculations from limited measures of community respiration.

Published
2008
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44. Temporal and spatial variability of sediment productivity on a fringing reef (Reunion Island, Western Indian Ocean)

Author

Taddei, Dorothée, Cuet, Pascale, Clavier, Jacques, Patrick, Frouin, Alarcon, Nicolas, Laboratoire d'Ecologie Marine (ECOMAR), Université de La Réunion (UR), 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), and 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 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)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Poster about Temporal and spatial variability of sediment productivity on a fringing reef (Reunion Island, Western Indian Ocean)

Published
2008

45. Spatial and temporal variability in benthic biogeochemical fluxes in the Thau lagoon associated with macrophytic and macrofaunal distribution

Author

Thouzeau, Gérard, Grall, J., Clavier, Jacques, Chauvaud, Laurent, Jean, F., Leynaert, Aude, Ni Longphuirt, S., Amice, Erwan, Amouroux, David, 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 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), and Thouzeau, Gérard

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2007

46. Carbon Fluxes at the Water-sediment Interface in Reunion Island Fringing Reef

Author

Taddei, Dorothée, Bucas, G., Clavier, Jacques, Cuet, Pascale, Patrick, Frouin, UnivBrestBU, AdminHAL, Laboratoire d'Ecologie Marine (ECOMAR), Université de La Réunion (UR), 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), and 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 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)

Subjects
Sediments, [SDE] Environmental Sciences, Metabolism, Reunion Island, [SDE]Environmental Sciences, Coral reef, Carbon
Abstract

International audience; To assess the contribution of soft-bottoms to the carbon cycle in coral reefs, the net community production (p) was measured in winter at 3 stations on La Saline inner reef flat (Reunion Island). Changes in pH and total alkalinity at different irradiances (I) were assessed using benthic chambers (0.2 m²) during a 1-h incubation. Mean grain size, the silt and clay load and chlorophyll a content of the sediments were analysed in each chamber. Daily community production (P), gross community production (Pg) and community respiration (R) were estimated from p-I curves and daily irradiance variations (PAR, 400-700 nm). Sediment characteristics and chlorophyll a contents did not differ between the three sites, except for the silt and clay fraction at one station. R being higher than Pg (84.88 ± 7.36 and -62.29 ± 3.34 mmolC m-2 d-1 respectively), P value reached 22.59 ± 5.66 mmolC m-2 d-1. The sediments were therefore heterotrophic with a mean Pg/R lower than 1 (0.74 ± 0.05) and appear to be a carbon source. Our data suggested the importance of the degradation process in the functioning of near-reef sediments.

Published
2007

47. Benthic O2 distribution and dynamics in a Mediterranean lagoon: an in situ microelectrode study

Author

Dedieu, K., Rabouille, C., Thouzeau, Gérard, Jean, F., Chauvaud, Laurent, Clavier, Jacques, Mesnage, V., Ogier, S., Thouzeau, Gérard, 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), and 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 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)

Subjects
[SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2007

48. Respiration, calcification and excretion of the invasive limpet, Crepidula fornicata L.: implications for carbon carbonate and nitrogen fluxes

Author

Martin, S., Thouzeau, Gérard, Chauvaud, Laurent, Jean, F., Guérin, L., Clavier, Jacques, 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 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), and Thouzeau, Gérard

Subjects
[SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2006

49. Mercury species benthic fluxes measurements in coastal environments as influenced by the biological activity

Author

Amouroux, David, Monperrus, Mathilde, Point, D., Tessier, E., Chauvaud, Laurent, Thouzeau, Gérard, Jean, F., Leynaert, Aude, Clavier, Jacques, Grall, J., Amice, Erwan, Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), 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), and 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 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)

Subjects
[SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
Abstract

International audience

Published
2004

50. La crépidule : identifier les mécanismes de sa prolifération et caractériser ses effets sur le milieu pour envisager sa gestion (Chantier : Rade de Brest)

Author

Thouzeau, Gerard, Chauvaud, Laurent, Clavier, Jacques, Donval, Anne, Guerin, Laurent, Jean, Fred, Le Hir, Maryvonne, Lorrain, Anne, Marc, Robert, Paulet, Yves-marie, Raffin, Coralie, Richard, Joëlle, and Richard, Marion

Abstract

En 1999, le risque écologique encouru par les écosystèmes côtiers soumis à la prolifération de la crépidule, Crepidula fornicata, a été pleinement reconnu par la communauté scientifique nationale et internationale. Au niveau national, le Programme National Environnement Côtier (PNEC) et le programme national LITEAU ont tous deux identifié des actions thématiques prioritaires sur la dynamique de prolifération de la crépidule et les interactions crépidule/bivalves exploités. Les actions du LEMAR (UMR 6539 CNRS) sur cette thématique s’inscrivent dans deux projets : 1 - La crépidule : identifier les mécanismes de sa prolifération et caractériser ses effets sur le milieu pour envisager sa gestion. » (LITEAU) 2 - Recrutement, milieu physique et interactions d'espèces en environnement côtier : cas des mollusques » (PNEC ART2) En rade de Brest, l’accent est mis sur l’interaction des cycles biologiques de la crépidule et de la coquille Saint-Jacques. Les objectifs poursuivis en rade de Brest s’articulent en 4 points, dans le cadre de LITEAU : 1- Dynamique de colonisation de la crépidule en rade de Brest : acquisition des paramètres de dynamique de population (caractéristiques du cycle reproducteur, déterminisme du recrutement, dispersion, croissance, sensibilité aux efflorescences toxiques...) ; 2- Impact de cette prolifération sur l’évolution de la nature sédimentaire des zones colonisées et l’enrichissement en matière organique (par le biais de l’activité alimentaire et de la production de biodépôts) ; 3- Modifications engendrées sur les peuplements benthiques dans leur globalité (sites ateliers). La strate à crépidules, au sens biosédimentaire et écologique, verra sa définition affinée et sa dynamique analysée en vue d'obtenir un modèle prévisionnel des évolutions possibles en matière de biodiversité ; 4- Rôle de la crépidule dans le contrôle de la production primaire phytoplanctonique (par le biais des activités de filtration et de production de biodépôts).

Published
2002

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