Consulta: creatorFacets:"Lecroart, Pascal"
Registros recuperados: 3
Data/hora: 03/06/2024 05:26:53

Bioturbation at the water-sediment interface of the Thau Lagoon: impact of shellfish farming
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Schmidt, Sabine; Gonzalez, Jean-louis; Lecroart, Pascal; Tronczynski, Jacek; Billy, Isabelle; Jouanneau, Jean-marie.
Quantifier les processus de remaniement sédimentaire procure une vision nouvelle du fonctionnement des écosystèmes benthiques de l'étang de Thau, lieu d'une importante production ostréicole. Afin d'évaluer les taux de bioturbation des sédiments de surface, des profils de deux traceurs radioactifs, le béryllium 7Be (T1/2 = 53 jours) et le thorium 234Th (T1/2 = 24.1 jours) ont été mesurés à partir de carottes sédimentaires prélevées entre décembre 2001 et décembre 2006. La sélection de plusieurs sites a permis de couvrir la diversité de l'étang de Thau : C4, T10, et T11 dans le bassin central, C5, T7 et T8 au niveau des secteurs ostréicoles, T2 et T4 à l'ouest du bassin, et T12 à l'est près de la zone industrielle. Le 234Th en excès (234Thxs ; i.e. apporté...
Tipo: Text
Palavras-chave: Mediterranean Lagoon; Radionuclides; Biodeposition; Sedimentation.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2584.pdf

The dynamics of phosphorus in turbid estuarine systems: Example of the Gironde estuary (France)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Deborde, Jonathan; Anschutz, Pierre; Chaillou, Gwenaelle; Etcheber, Henri; Commarieu, Marc-vincent; Lecroart, Pascal; Abril, Gwenael.
Suspended particles and surface waters were collected in the Gironde estuary (southwestern France) along the salinity gradient. Dissolved inorganic phosphorus (DIP) was analyzed in the filtered surface waters. The suspended particles were sequentially leached to determine five fractions of phosphorus: exchangeable or loosely sorbed P, reactive Fe-bound P, refractory Fe oxide-bound P, P associated with apatite and carbonates, and organic P. Experiments were conducted to determine the effects of temperature, salinity, and DIP concentration on phosphorus sorption/desorption processes. The concentration and distribution of particulate phosphorus was homogeneous along the salinity gradient of the estuary, whereas it was variable in time and space in the...
Tipo: Text
Ano: 2007
URL: https://archimer.ifremer.fr/doc/00603/71538/69943.pdf

Experimental Assessment of the Effects of Temperature and Food Availability on Particle Mixing by the Bivalve Abra alba Using New Image Analysis Techniques
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Bernard, Guillaume; Duchene, Jean-claude; Romero-ramirez, Alicia; Lecroart, Pascal; Maire, Olivier; Ciutat, Aurelie; Deflandre, Bruno; Gremare, Antoine.
The effects of temperature and food addition on particle mixing in the deposit-feeding bivalve Abra alba were assessed using an experimental approach allowing for the tracking of individual fluorescent particle (luminophore) displacements. This allowed for the computations of vertical profiles of a set of parameters describing particle mixing. The frequency of luminophore displacements (jumps) was assessed through the measurement of both waiting times (i.e., the time lapses between two consecutive jumps of the same luminophore) and normalized numbers of jumps (i.e., the numbers of jumps detected in a given area divided by the number of luminophores in this area). Jump characteristics included the direction, duration and length of each jump. Particle...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00375/48615/49432.pdf