Biosurveillance de la pollution de la lagune de Bizerte (Tunisie) par l’analyse comparée des niveaux de contamination et de l’écotoxicité des sédiments et du biote
L’objectif de cette thèse est le diagnostic de l’état de santé de la lagune de Bizerte par une approche multi-marqueurs (chimique, biochimique et morphométrique) et multi-compartiments (sédiment et biote). Pour atteindre cet objectif, les modèles biologiques choisis sont la moule Mytilus galloprovincialis et le poisson gobie Zosterisessor ophiocephalus. Ces deux espèces sont largement répandues dans la lagune de Bizerte et la mer Méditerranée. Dans une première partie et afin d’estimer les niveaux de contamination de la lagune de Bizerte par les polluants organiques persistants (POPs), des analyses chimiques, granulométriques et minéralogiques (COT) de sédiments superficiels ont été réalisées. Par la suite la toxicité potentielle des sédiments a été évaluée par une batterie de bioessais. Dans une troisième partie la biodisponibilité et l’impact écotoxicologique des POPs étudiés ont été évalués par l’accumulation de ces contaminants au niveau des deux organismes indicateurs choisis et l’étude des réponses biologiques associées à travers quelques biomarqueurs tels que la catalase (CAT), l’acide thiobarbiturique (TBARS); l’Ethoxyrésorufine O-dééthylase (EROD); la glutathion-S-transférase (GST) et l'acétylcholinestérase (AChE). Les principaux résultats des analyses chimiques révèlent une contamination générale des sédiments et organismes étudiés par les POPs. Les niveaux de contamination sont fonction de l’espèce et de la station étudiée. La comparaison de nos valeurs avec les données de la littérature a montré que les niveaux de contamination de la lagune sont similaires ou légèrement inférieurs à ceux enregistrés dans des écosystèmes équivalents dans d’autres pays du monde. L’estimation de la toxicité des sédiments au moyen des valeurs guides sédimentaires (ERL, ERM, TEL et PEL) et trois tests biologiques (Microtox®, SOS-Chromotest® et test MELA) ont montré que les sédiments des stations du canal de Bizerte S1 et S3 représentent un danger accru pour les organismes aquatiques. Nos résultats ont montré que les biomarqueurs mesurés chez les deux espèces choisies sont des paramètres sensibles et inductibles permettant de qualifier l’état de santé des organismes et la qualité globale du milieu étudié. Les marqueurs morphométriques contrairement aux marqueurs biochimiques n’ont pas permis de discriminer les différents sites étudiés. Contrairement aux poissons, il a été démontré chez les moules que les facteurs abiotiques ont une influence sur les concentrations en POPs et les réponses des biomarqueurs.Au vu de l’ensemble de ces résultats, il apparaît que cette approche intégrative associant des mesures chimiques et écotoxicologiques représente un bon moyen pour évaluer la qualité de l’environnement notamment dans le cadre de programmes de biosurveillance.
(10/06/2014)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Assessment of Reactivity and Mobility of MTE in Surface Sediments in Morbihan Coast (South Brittany, France)
(08/06/2014)
LGO, UBS, IFREMER, UBO EPE, CNRS, GEOARCHI, UBS, UBO EPE, IBSHS, UBO EPE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LDO, INSU - CNRS, UBO EPE, CNRS
Oxidative stress in relation to reproduction, contaminants, gender and age in a long-lived seabird
Reproduction is a demanding activity for animals, since they must produce, and in some cases protect and provision, their young. It is often overlooked that demands of reproduction may also be exacerbated by exposure to contaminants. In this study, we make use of an exceptional long-term dataset to perform a cross-sectional study on the long-lived wandering albatross (Diomedea exulans) in order to test the effects of reproduction, persistent organic pollutants [POPs: pesticides and polychlorinated biphenyls (PCBs)], mercury, individual age (3–47 years), and sex on the levels of plasma oxidative damage and inflammation. The results of our study support the hypothesis that oxidative damage may be a physiological cost of reproduction and that individuals carrying higher levels of organic or non-organic contaminants have higher oxidative damage. Levels of the inflammatory protein haptoglobin were similar between breeding and nonbreeding birds, with the exception of breeding males which had the lowest levels of haptoglobin. Our data also show an effect of age and of organic contaminants on the plasma oxidative damage level, but not on plasma haptoglobin. In addition, plasma oxidative damage level increased with red blood cell mercury concentration in females but not in males. Hence, our study highlights that the harmful effects of contaminants may come through interaction with factors like life stage or gender, suggesting potential for high variation in susceptibility to contamination among individuals.
(Oecologia. vol. 175, n° 0029-8549, pp. 1107 - 1116, 04/06/2014)
CEBC, INRA, ULR, CNRS, LIENSs, INSU - CNRS, ULR, CNRS, BGS, UB, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Recent sediment transport and deposition in the Cap-Ferret Canyon, South-East margin of Bay of Biscay
The Cap-Ferret Canyon (CFC), a major morphologic feature of the eastern margin of the Bay of Biscay, occupies a deep structural depression that opens about 60 km southwest of the Gironde Estuary. Detailed depth profiles of the particle-reactive radionuclides 234Th and 210Pb in interface sediments were used to characterise the present sedimentation (bioturbation, sediment mass accumulation, and focusing) in the CFC region. Two bathymetric transects were sampled along the CFC axis and the southern adjacent margin. Particle fluxes were recorded from the nearby Landes Plateau by means of sediment traps in 2006 and 2007. This dataset provides a new and comprehensive view of particulate matter transfer in the Cap-Ferret Canyon region, through a direct comparison of the canyon with the adjacent southern margin. Radionuclide profiles (234Th and 210Pb) and mass fluxes demonstrate that significant particle dynamics occur on the SE Aquitanian margin in comparison with nearby margins. The results also suggest show three distinct areas in terms of sedimentary activity. In the upper canyon (<500 m), there is little net sediment accumulation, suggesting a by-pass area. Sediment focusing is apparent at the middle canyon (500–1500 m), that therefore acts as a depocenter for particles from the shelf and the upper canyon. The lower canyon (>2000 m) can be considered inactive at annual or decadal scales. In contrast with the slow and continuous accumulation of relatively fresh material that characterises the middle canyon, the lower canyon receives pulses of sediment via gravity flows on longer time scales. At decadal scale, the CFC can be considered as a relatively quiescent canyon. The disconnection of the CFC from major sources of sediment delivery seems to limit its efficiency in particle transfer from coastal areas to the adjacent ocean basin.
(Deep Sea Research Part II: Topical Studies in Oceanography. vol. 104, n° 0967-0645, pp. 134-144, 01/06/2014)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, BIAF, UA, ICM, CSIC, JAMSTEC, IFREMER, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, INPL
Benthic foraminiferal thanatocoenoses from the Cap-Ferret Canyon area (NE Atlantic): A complex interplay between hydro-sedimentary and biological processes
(Deep Sea Research Part II: Topical Studies in Oceanography. vol. 104, n° 0967-0645, pp. 145-163, 01/06/2014)
BIAF, UA, MIO, IRD, AMU, INSU - CNRS, UTLN, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS
Effet de pesticides sur les micro-algues du continuum eau douce-eau marine : Influence de la matière organique dissoute naturelle ?
Le poster résume les principaux objectifs des projets AAP COTE IMPACT et EC2CO COMPACT. Les projets IMPACT et COMPACT constituent une approche originale combinant : du réalisme écologique, par la prise en compte des réponses au niveau spécifique mais également au niveau des communautés naturelles ; du réalisme environnemental, en considérant l'effet d'herbicides seuls et en mélange, en interaction avec la matière organique dissoute naturelle. Ces projets permettront d'améliorer les connaissances sur les effets du S-métolachlore, un herbicide aux effets peu documentés mais pourtant très utilisé et retrouvé fréquemment en eaux côtières (Bassin d'Arcachon, estuaire de la Charente).
(pp. 1, 21/05/2014)
IFREMER, UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
New records of Spio symphyta and Spio martinensis (‘Polychaeta’: Canalipalpata: Spionidae) from Arcachon Bay (France), NE Atlantic
This paper presents new records of Spio symphyta Meißner et al., 2011 and Spio martinensis Mesnil, 1896 (‘Polychaeta’: Canalipalpata: Spionidae) from Arcachon Bay (southern Bay of Biscay). For both species the new records represent an extension of their known distributional range. The two species have probably been present in Arcachon Bay for several years but were confused with other species of the genus Spio. Spio symphyta was identified at five locations in Arcachon Bay in 2009 and 2013 and S. martinensis at three stations in 2012 and 2013. A detailed and illustrated description of specimens from Arcachon Bay is provided. Important characters of Spio spp. occurring in the area are compared.
(Marine Biodiversity. vol. 45, n° 1867-1616, pp. 77-86, 17/05/2014)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LMU
Upwind Stabilized Finite Element Modelling of Non-hydrostatic Wave Breaking and Run-up
In the following report a new methodology is presented to model the propagation, wave breaking and run-up of waves in coastal zones. We represent the different coastal phenomena through the coupling of non-linear shallow water equations with the extended Boussinesq equations of Madsen and Sørensen. Each of the involved equations has a major role in describing a particular physical behaviour of the wave: the latter equations permit to model the propagation, while the non-linear shallow water ones lead waves to locally converge into discontinuities. We start from the third-order stabilized finite element scheme for the Boussinesq equations, developed in a previous scientific work (Ricchiuto and Filippini, J.Comput.Phys. 2014) and develop a non-linear variant, and detach the dispersive from the shallow water terms. A shock-capturing technique based on local non-linear mass lumping that permits in the shallow water regions to degrade locally the scheme to a first-order one across bores (shocks) and dry fronts is proposed. As for the detection of the breaking fronts, the shallow water areas, this involves physics based breaking criteria. We present different definitions of the breaking criterion, including a local implementation of the convective criterion of (Bjørkavåg and H. Kalisch, Phys.Letters A 2011), and the hybrid models of (Kazolea et. al, J.Comput.Phys. 2014), and (Tonelli and Petti, J.Hydr.Res. 2011). The behavior of different breaking criteria is investigated on several cases for which experimental data are available.
(12/05/2014)
BACCHUS, Inria, UB, CNRS, IMB, UB, Bordeaux INP, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
First record of Naineris setosa (Verrill, 1900) (Annelida: Polychaeta: Orbiniidae) in the Western Mediterranean Sea
The Polychaeta Naineris setosa (Verrill, 1900) is reported for the first time in the Western Mediterranen Sea. Several specimens were collected in 2012 and 2013 in Boughrara Lagoon (Tunisia). The vector of introduction of N. setosa likely commercial shipping because Gabes is an international harbour with dense shipping traffic. A detailed description of specimens from Boughrara Lagoon is provided in this paper.
(BioInvasions Records. vol. 3, n° 2242-1300, pp. 83-88, 12/05/2014)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Use of passive samplers (POCIS and SPMD) for the evaluation of the efficiency of wastewater tertiary treatments
Our objective is to study some advanced processes, such as ozonation (O3) or Granular Activated Carbon (GAC) as example, used in tertiary stage of wastewater treatment plants (WWTP). The challenges when studying such processes is to be able to measure organic micropollutants at very low concentrations (ng/L). To achieve this goal, passive samplers (PS) like POCIS (Polar Organic Chemical Integrative Sampler) and SPMD (Semi-Permeable Membrane Device) were used. The results of chemical analyses on PS were compared with those on grab water samples. Four one-month-long sampling campaigns were carried out in 3 different WWTP: 1) O3 (full-scale) followed by GAC (pilot) in WWTP A, 2) O3 only (full-scale) in the same WWTP A, 3) GAC (pilot) in WWTP B, 4) polishing pond (full-scale) in WWTP C. In all campaigns, POCIS were exposed in water during 14 days and SPMD during 28 days. To be able to compare these 4 campaigns and the molecule concentrations upstream and downstream the tertiary treatment, POCIS and SPMD were always immersed in an aquarium in the same controlled experimental conditions of flow (280 mL/min), temperature (20° C) and light. To insure quality of data, POCIS and SPMD were exposed in triplicate and field blanks were realized (i.e. PS exposed to the ambient air). In parallel, 2h composite water samples were collected at D0, D14 and D28. Targeted chemical analyses were performed on POCIS extracts for 117 hydrophilic compounds belonging to pharmaceutical, hormone, pesticide and alkylphenol classes and on SPMD extracts for 46 lipophilic compounds belonging to chlorine pesticides, Polycyclic Aromatic Hydrocarbon, PolyChloroBiphenyl, PolyBrominated DiphenylEthers classes. Hydrophilic compounds and PAH were also analysed in water samples. We will present results obtained for SPMD and POCIS. As an example, compared to grab sampling, POCIS allowed detecting 7 more pharmaceuticals in influent of tertiary treatments and 4 more in effluents in the 2 first sampling campaigns. Nevertheless, information on process efficiency is the same since the decrease of pharmaceutical concentrations after advanced water treatment is in the same order of magnitude with grab and passive sampling in the 2 first sampling campaigns. Hence, POCIS appears as an interesting tool to characterize tertiary stages of WWTPs with analysis of organic micropollutants at very low concentrations.
(pp. 1, 11/05/2014)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS