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See detailFrom seascape level to functional ecology: A case study over P. oceanica seagrass meadows in Calvi, Corsica
Lapeyra Martin, Jon ULiege; Abadie, Arnaud; Richir, Jonathan ULiege et al

in Actes du colloque Carhamb'ar 2017 (in press)

see long abstract

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See detailSTARECAPMED, des indices pour La Méditerranée
Leduc, Michèle; Abadie, Arnaud; Donnay, Annick et al

in Cartographie des habitats marins benthiques : de l’acquisition à la restitution (2017)

Le projet STARECAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) a pour objectif (i) d’améliorer la compréhension du ... [more ▼]

Le projet STARECAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) a pour objectif (i) d’améliorer la compréhension du fonctionnement des différents écosystèmes marins côtiers présents en Méditerranée et (ii) de décrire l’influence des activités humaines sur les processus qui gouvernent ce fonctionnement. La baie de Calvi, par sa situation exceptionnelle, est un site de référence de la Directive Européenne Cadre sur l’Eau (DCE), du monitoring de l’eutrophisation et de la contamination par les éléments traces. La Station de recherches océanographiques STARESO, implantée dans la baie depuis près de 50 ans, possède un accès unique à la mer et de nombreuses facilités logistiques. Elle a développé au fil du temps une expertise scientifique reposant notamment sur l’acquisition de longues séries temporelles de données environnementales. Ensemble, Baie et Station s’intègrent en un site atelier dédié à l’évaluation de l’état de santé des écosystèmes marins côtiers de Méditerranée Nord-Occidentale. En particulier, différents indices et indicateurs y sont développés en collaboration avec de nombreux laboratoires partenaires. Ainsi, nous avons développé, d’une part, une version non destructive de l’indice PREI (Posidonia Rapid Easy Index) d’évaluation de la qualité des eaux côtières reposant sur le suivi des herbiers à Posidonia oceanica, et d’autre part, deux indices d’évaluation de l’impact des ancrages, puis testé   l’indice EBQI (Ecosystem Based Quality Index), une approche sur la diversité écologique. Les indices TEPI (Trace Element Pollution Index) et TESVI (Trace Element Spatial Variation Index) permettent d’évaluer la contamination par les éléments traces. Le BeMSI (BEnthic Methodology Simplification) est un nouvel indicateur de la qualité du milieu défini à partir de la composition des peuplements macrobenthiques des substrats meubles et plus généralement, l’indice LIMA traduit l’attrait paysager et la richesse patrimoniale du benthos méditerranéen entre 0 et –40 m. Quant à l’indice ICAR (Indice paysager CAulerpa Racemosa), il permet d’évaluer les niveaux de colonisation par l’algue invasive Caulerpa cylindracea. Enfin, une approche innovante reposant sur l’enregistrement des sons permet d’évaluer la qualité du milieu à partir d’un paysage acoustique sous-marin. En conclusion, le développement et l’application combinée de ces différents indices et indicateurs développés dans le cadre du programme pluridisciplinaire STARECAPMED fournissent une estimation globale des états du milieu côtier méditerranéen à différents niveaux d’organisation, depuis l’espèce jusqu’à l’écosystème. De plus, leur mise en œuvre dans ce même site atelier privilégié permet de les confronter, de les ajuster et de les intercalibrer pour à terme les proposer aux gestionnaires du milieu côtier. [less ▲]

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See detailTrace element concentrations in the apex predator swordfish (Xiphias gladius) from a Mediterranean fishery and risk assessment for consumers
Gobert, Sylvie ULiege; Pasqualini, Vanina; Dijoux, Jessica et al

in Marine Pollution Bulletin (2017), 120

Swordfish (Xiphias gladius L., 1758) is an apex predator, highly migratory meso-pelagic fish widely distributed in the Atlantic Ocean and Mediterranean. As top predators, this fish may be the end ... [more ▼]

Swordfish (Xiphias gladius L., 1758) is an apex predator, highly migratory meso-pelagic fish widely distributed in the Atlantic Ocean and Mediterranean. As top predators, this fish may be the end reservoir of the bioaccumulation of trace elements in a food chain because they occupy higher trophic levels and are an important food source, causing them to be potentially hazardous to consume. This study aims to investigate the concentration of 18 trace elements of Swordfish, caught in the Mediterranean Sea and to discuss human exposure risks. The mean element levels in the fish muscles were clearly below the maximum allowable concentrations established by International food safety regulations. The data suggested that the risk is minor and acceptable for human health. The findings of this study amplify the scarce database on contaminants available, especially new data on “emerging elements”, for this species from the Mediterranean Sea. [less ▲]

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See detailExploring a Mediterranean mesozooplankton 13 year time-series.
Fullgrabe, Lovina; Richir, Jonathan ULiege; Batigny, Antoine et al

Poster (2016, December 16)

Zooplankton plays diverse crucial roles within the marine ecosystem and can also be used as bio- indicator of climate changes since it is very sensitive to environmental changes. Therefore it is essential ... [more ▼]

Zooplankton plays diverse crucial roles within the marine ecosystem and can also be used as bio- indicator of climate changes since it is very sensitive to environmental changes. Therefore it is essential to consider long-term plankton series. Given the analysis of plankton samples is time- consuming, it requires an effective and rapid analytical method. We have used in this work a supervised learning approach adapted for the semi-automatic classification of digital images of the mesozooplankton of the Bay of Calvi (Corsica, France) by using the Zoo/PhytoImage software. Together with a 11-years long zooplankton time-series, a set of nine environmental variables were monitored in order to identify controlling factors and determine whether the communities were sensitive to global environmental changes. The main components of the mesozooplankton community were characterized by both seasonal and inter-annual variability. Additionally, variation of holoplankton and meroplankton differentiated one from each other. The holoplanktonic community could be split into two subgroups according to its variation in function of the environment: cladocerans and appendicularians, and to a lesser extent, copepods on one hand, and cnidarians, chaetognathes and thaliaceans, on the other hand. Regarding inter-annual variation, one year (2007) showed particularly low production of total zooplankton which was also the case for all the different holoplanktonic taxa. Accounting for that phenomenon were identified some potentially underlying environmental factors. Finally, although water temperature increased significantly over the last years along with the frequency of marine heat wave events, no evident change in the global zooplankton composition was observed yet. [less ▲]

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See detailAssessing edge-effects in Posidonia oceanica seagrass meadows: A multidisciplinary approach
Lapeyra, Jon; Abadie, Arnaud; Lejeune, Pierre et al

Conference (2016, December)

Structural boundaries in ecosystems play an important role both in the context of seascape architecture, ecological processes and biodiversity. The Mediterranean Seagrass Posidonia oceanica (L.) Delile is ... [more ▼]

Structural boundaries in ecosystems play an important role both in the context of seascape architecture, ecological processes and biodiversity. The Mediterranean Seagrass Posidonia oceanica (L.) Delile is considered an ecosystem engineer species, forming habitats of great ecological value and providing many ecosystem services. This study aims to (1) determine whether there are differences between seagrass-sand corridors edges and the adjacent continuous meadow, and (2) investigate whether anthropogenic pressures can cause disturbances in the measured parameters along the edges and the meadow. We have developed a multidisciplinary approach combining plant physiology, faunal canopy community studies and seagrass structural parameters characterization. We performed in situ chlorophyll fluorescence measurements using a Pulse Amplitude Modulated (Diving-PAM) fluorometry in order to assess the photosynthetic rate of the shoots. Vagile macrofauna of the leaf stratum was sampled by a hand-towed net, and the major taxonomic groups were sorted, counted, and identified. Meadow’s biometric measurements and the epiphytic biomass were also determined. Regarding edge-meadow matrix, results have shown highest differences on matrix structural parameters such as shoot density and shoot type proportions. Shoot density was found to decrease in edges considerably. We found c.a to 60 % plagiotropic shoots on edges while in continuous meadow orthotropics were predominant (up to 90 %). Howerver vagile-fauna population densities and diversity did not differ significantly among stations studied, neither by sites. Photosynthetic rate and leaf surface values also did not show changes between edges and continuous meadow. However, results did show that plagiotropic shoots had higher photosynthetic rate than orthotropics, and also that epiphyte abundance sorted out to be much higher (up to 54 %) on edges. [less ▲]

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See detailContrôle de la variabilité interannuelle de la composition du phytoplancton de la Baie de Calvi (Corse) par les facteurs environnementaux
Goffart, Anne ULiege; Andral, Bruno; Baldi, Yoann et al

Conference (2016, November)

Le but de la présentation est de synthétiser les connaissances sur le contrôle de la dynamique du phytoplancton par les contraintes environnementales dans un site de référence méditerranéen. L’étude est ... [more ▼]

Le but de la présentation est de synthétiser les connaissances sur le contrôle de la dynamique du phytoplancton par les contraintes environnementales dans un site de référence méditerranéen. L’étude est réalisée en Baie de Calvi (Corse) à la station PHYTOCLY (42°34.85'N, 08°43.71'E) où des séries temporelles haute fréquence de données physiques, chimiques et biologiques sont réalisées depuis 1979. Depuis 2006, l’acquisition des données de subsurface et le traitement des échantillons, qui inclut des analyses HPLC de contenu pigmentaire du phytoplancton et des comptages de flore totale, sont réalisés grâce au soutien de la DCE. En Baie de Calvi, l’intensité de la rigueur hivernale, identifiée par deux proxys, la température de l’eau et le nombre de jours de vent fort, contrôle le réapprovisionnement en sels nutritifs des couches de surface et le développement du bloom phytoplanctonique (détails dans Goffart et al., 2015, Progress in Oceanography). Lors des années caractérisées par un hiver rigoureux (e.g. 2010), le bloom phytoplanctonique hivernal se développe pendant la période d’eau froide (eau de subsurface ≤13.5°C). Il est dominé par les diatomées et les cryptophycées, deux groupes qui montrent une préférence marquée pour les eaux froides et riches en sels nutritifs. Lorsque l’hiver est très doux (e.g. 2007), la disponibilité en sels nutritifs est réduite et le bloom ne se développe pas. Les diatomées et les cryptophycées sont absentes, et les communautés phytoplanctoniques sont dominées par les prymnesiophycées pico- et nanoplanctoniques et les cyanobactéries. Les résultats de l’étude permettent aussi : • de fixer les limites de la variabilité naturelle du phytoplancton dans un site de référence méditerranéen, • d’expliquer les variations interannuelles de biomasse et de composition phytoplanctonique, • de définir les préférences écologiques des différents groupes phytoplanctoniques, • d’établir des courbes d’évolution saisonnière des principaux groupes phytoplanctoniques qui intègrent la variabilité interannuelle liée aux variations climatiques. La connaissance acquise au cours de cette étude permet de contribuer au développement d’indices de qualité intégrant la composition du phytoplancton (e.g. indice de composition I C MEDIT) et de tester des méthodes de surveillance à grande échelle (e.g. croisement des suivis pigmentaires réalisés à haute fréquence et de l’imagerie satellitaire), contribuant ainsi à la mise en œuvre des politiques publiques (DCE, DCSMM). [less ▲]

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See detailEcoNum, a research unit devoted to marine environment monitoring
Richir, Jonathan ULiege; Batigny, Antoine; Georges, Nadège et al

Conference (2016, October 27)

The monitoring of coastal environments remains a research domain of great interest and concern. Coastal ecosystems are threatened by natural and human-induced stressors and are, as transitional ... [more ▼]

The monitoring of coastal environments remains a research domain of great interest and concern. Coastal ecosystems are threatened by natural and human-induced stressors and are, as transitional environments, particularly sensitive to disturbances. EcoNum first research thematic revolves around hermatypic corals, calcifying organisms, and their adaptation potentials to environmental changes including by using original and patented chemostats. The studied organisms are grown and maintained in artificial mesocosms that simulate environmental conditions of a natural system. This infrastructure allows to perform long-term experiments, giving time to organisms to adapt to the tested conditions (e.g., increased temperature or lowered pH). Longer-term studies have demonstrated that many organisms are more resistant to environmental stressors than previously observed on the short-term. EcoNum also studies coastal plankton abundance and diversity. Plankton is particularly sensitive to physicochemical changes of water bodies. The classification and the enumeration of planktonic organisms require specialized tools in order to analyse time series of multiple samples. EcoNum has developed a software for the semi-automatic classification of planktonic organisms called Zoo/PhytoImage. This software has been used to study a 10-year time series of coastal Mediterranean zooplankton samples. The concomitant analysis of environmental parameters registered at high frequency with specific statistical tools such as the R package pastecs allows to understand the processes governing the changes observed in plankton assemblages. The use and the development of statistical tools in R (e.g., Zoo/Phytoimage, pastecs) is a priority of EcoNum to favour open access knowledge and reproductive sciences. EcoNum research topics also focus on coastal ecotoxicology. Chemicals, including trace elements, remain contaminants of concern, mainly in coastal environments that are the final sink of inland pollution sources. The chemical integrity of coastal ecosystems thus has to be accurately monitored. The partitioning of chemicals between their dissolved, particulate and sedimentary phases does not provide information on their bioavailability. EcoNum thus monitors coastal waters using bioindicator species such as seagrasses, mussels or sand worms. A global map of the contamination of the Mediterranean by trace elements has been drawn using seagrasses has bioindicator species. EcoNum also studies trace element ecology and toxicology. For instance, it has demonstrated the toxicity of copper on the coral Seriatopora hystrix and it's symbiont's photosynthetic processes, or its bioaccumulation and basipetal translocation towards rhizomes in the seagrass Posidonia oceanica as reserve nutrient for subsequent leaf growth. Finally, coastal vegetated systems are potential carbon thinks (or sources) in the global carbon cycle. Therefore, EcoNum studies the primary productivity of seagrass meadows, from the individual to the community, with measuring techniques as diverse as PAM-fluorometry or biomass production determination. To conclude, EcoNum is a research unit devoted to marine environment monitoring. It develops research thematics on major coastal communities such as coral reefs, seagrass beds or plankton assemblages and studies their natural dynamics and the effects of stressors on their global functioning. [less ▲]

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See detailA one year survey of seagrass primary productivity using the diving-PAM technique
Richir, Jonathan ULiege; Abadie, Arnaud; Grosjean, Philippe et al

Poster (2016, October 18)

Marine magnoliophytes are major primary producers in coastal benthic habitats worldwide. They play a crucial role in the global carbon cycle (one of the more efficient blue carbon wells). Hence, it is ... [more ▼]

Marine magnoliophytes are major primary producers in coastal benthic habitats worldwide. They play a crucial role in the global carbon cycle (one of the more efficient blue carbon wells). Hence, it is necessary to characterise the eco-systemic services seagrass meadows provide. Posidonia oceanica (L.) Delile, the main Mediterranean seagrass species, has high foliar and belowground biomass production. Several methods have been used so far to measure its primary production (e.g., using incubation bells, optodes, biomass and elementary content measurements). A less used method relies on chlorophyll fluorescence measurements through the Pulse Amplitude Modulated (PAM) fluorometry method (Diving - PAM). In the framework of the STARECAPMED project, this study aimed to determine weekly to bimonthly over a one-year period the photosynthetic responses (Yield, relative Electron Transfer Rate, Rapid Light Curve) of P. oceanica. The survey was performed at 10m depth in a pristine meadow (Calvi, Corsica, France). To obtain reliable and comparable data, the protocol was standardized: measurements were performed on the convex middle part of the third leaf, at zenith, during shiny and calm weather days. Results showed that the plant displayed a well-marked seasonality. The mean ETR (μmol e- m-2 s-1 ) of the plant ranged from 2.17 in winter to 21.9 in summer and was linearly correlated throughout the year with the in situ irradiance (PAR irradiance taken perpendicularly to the surface, in the average leaf orientation). The ETR plateaus of the RLCs, ranging from 10.9 to 35.0, and their corresponding maximum PAR intensities evolved similarly. These results demonstrated both the adaptation and the seasonal plasticity of the meadow’s photosynthetic system. Overall the non-destructive PAM technique is a powerful and cost-effective tool to assess the primary productivity of seagrass meadows where other techniques (e.g. optodes) cannot be used and when direct sampling (e.g. biomass measurements) is not allowed. [less ▲]

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See detailEnvironmental monitoring: between science and decision-making
Richir, Jonathan ULiege; Gobert, Sylvie ULiege; Lejeune, Pierre et al

Scientific conference (2016, April 13)

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See detailEstimating carbon fluxes in a Posidonia oceanica system: Paradox of the bacterial carbon demand
Velimirov, Branko; Lejeune, Pierre; Kirschner, A. et al

in Estuarine Coastal & Shelf Science (2016), 171

A mass balance ecosystemic approach, based on bacterial carbon demands and primary production data, was used to investigate if the bacterial community (freewater bacterioplankton and benthic bacteria of ... [more ▼]

A mass balance ecosystemic approach, based on bacterial carbon demands and primary production data, was used to investigate if the bacterial community (freewater bacterioplankton and benthic bacteria of the oxygenated sediment layer) could be sustained by the main primary producers (Posidonia oceanica and its epiphytes, adjacent macroalgae and phytoplankton communities; hereafter called the P. oceanica system) of a non-eutrophic Mediterranean bay. Unexpectedly, the findings of this study differed from previous works that used benthic incubation chamber and O2 optode methods. In this study, data were grouped in two categories, corresponding to two time periods, according to the seawater temperature regime (<18 °C or >18 °C): from May to October and from November to April. Between May and October, the produced benthic macrophyte tissues could not provide the carbon required by the bacteria of the oxygenated sediment layer, showing that the balance production of the investigated bay was clearly heterotrophic (i.e. negative) during this time period. In contrast, between November and April, benthic bacteria respiration nearly equated to carbon production. When integrating the open water carbon dynamics above the meadow in the model, a negative carbon balance was still observed between May and October, while a slight carbon excess was noticed between November and April. In the light of these findings, the carbon balance being negative on an annual basis, alternative carbon sources are required for the maintenance of the bacterial carbon production. [less ▲]

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See detailPassive acoustic recording of Ophidion rochei calling activity in Calvi Bay (France)
Kever, Loïc ULiege; Lejeune, Pierre; Michel, Loïc ULiege et al

in Marine Ecology (2016)

Passive acoustic recording (PAR) systems are non-invasive and allow researchers to collect data on large spatial and temporal scales. Since fish sounds are species-specific and repetitive, PAR can provide ... [more ▼]

Passive acoustic recording (PAR) systems are non-invasive and allow researchers to collect data on large spatial and temporal scales. Since fish sounds are species-specific and repetitive, PAR can provide a large amount of data about spatio-temporal variation in fish distribution and behaviors. Ophidion rochei is a sand-dwelling species from Mediterranean and Black Sea meaning the behavior of this discreet nocturnal fish cannot be observed in the field. Fortunately, male O. rochei produce long multiple-pulsed calls that are easy to identify. The aim of this study was to determine that male calls are linked to reproduction behaviors. If so, PAR would allow a fine description of the seasonal and daily cycles in O. rochei reproduction. A hydrophone was deployed from 18 July 2011 to 21 June 2012 and from 7 June 2013 to 2 July 2013 on a sandy area (42.5801° N, 8.7285° E) in front of the STARESO research station (NW Corsica). Male sounds were obtained only at night from late spring to early fall. The annual sound production period corresponds to the reproductive season of O. rochei. Sound production followed diel cycles: it was sustained for the entire night at the beginning of the sound production season but limited to shorter periods in the evening during the second half of the season. These differences in daily and seasonal sound production tempo can be used in future recordings to make inter-annual comparisons and estimate the physiological state of the fish. [less ▲]

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See detailTemporal evolution of sand corridors in a Posidonia oceanica seascape: a 15-years study
Gobert, Sylvie ULiege; Lepoint, Gilles ULiege; Pelaprat, Corinne et al

in Mediterranean Marine Science (2016), 17(3), 777-784

The spatial dynamic of Posidonia oceanica meadows is a process extending over centuries. This paper shows evidence of the natural dynamics of P. oceanica “shifting intermattes” or “sand corridors” ... [more ▼]

The spatial dynamic of Posidonia oceanica meadows is a process extending over centuries. This paper shows evidence of the natural dynamics of P. oceanica “shifting intermattes” or “sand corridors” (hereafter SCs): unvegetated patches within a dense meadow. We studied features and temporal evolution (2001-2015) of 5 SCs in the Calvi Bay (Corsica) at 15 m depth and followed the characteristics the P. oceanica meadow lining the edge of patches. All SCs show a similar morphology. The eroded side is a vertical edge where roots, rhizomes and sediments are visible, when on the opposite colonized side, the sand is at the same level as the continuous meadow. The vertical edge reaches a maximum height of 160 cm and is eroded by orbital bottom currents with a maximum speed of 12 cm.s-1, the erosion speed ranging from 0.6 to 15 cm.y-1. SCs progress toward the coastline with a mean speed of 10 cm.y-1, the rate of colonization by P. oceanica shoots ranging from 1.5 to 21 cm.y-1. We calculated that the studied SCs would reach the coastline within 500 to 600 years. We finally discuss the implication of such dynamic in the framework of meadows’ colonization assessment and the seascape dynamic. [less ▲]

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See detailFrom mechanical to chemical impact of anchoring in seagrasses: the premises of anthropogenic patch generation in Posidonia oceanica meadows
Abadie, Arnaud ULiege; Lejeune, Pierre; Pergent, Gérard et al

in Marine Pollution Bulletin (2016), 109(1), 61-71

Intensive anchoring of leisure boats in seagrass meadows leads to mechanical damages. This anthropogenic impact creates bare mat patches that are not easily recolonized by the plant. Several tools are ... [more ▼]

Intensive anchoring of leisure boats in seagrass meadows leads to mechanical damages. This anthropogenic impact creates bare mat patches that are not easily recolonized by the plant. Several tools are used to study human impacts on the structure of seagrass meadows but they are not able to assess the indirect and long term implication of mechanical destruction. We chose to investigate the possible changes in the substrate chemistry given contrasted boat impacts. Our observations show that hydrogen sulfide concentrations remain high at 15 and 20 m depth (42.6 µM and 18.8 µM) several months after the highest period of anchoring during the summer. Moreover, our multidisciplinary study reveals that anchoring impacts of large boats at 15 and 20 m depth can potentially change the seascape structure. By taking into account both structural and chemical assessments, different managing strategies must be applied for coastal areas under anthropogenic pressures. [less ▲]

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See detailSTAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts: The STARECAPMED project
Richir, Jonathan ULiege; Abadie, Arnaud ULiege; Binard, Marc ULiege et al

Conference (2015, November 08)

The Marine and Oceanographic Research Station STARESO in the Calvi Bay, Corsica (France), is a unique tool in a preserved natural site that includes all the characteristic ecosystems of the Mediterranean ... [more ▼]

The Marine and Oceanographic Research Station STARESO in the Calvi Bay, Corsica (France), is a unique tool in a preserved natural site that includes all the characteristic ecosystems of the Mediterranean littoral. The station, established in 1970, has archived environmental data for decades. The STARECAPMED project, multidisciplinary, articulates itself around these two main features. Its objective is to understand how human activities can interact with the fundamental processes that govern the functioning of the different coastal ecosystems of a Mediterranean bay. The understanding of these interactions involves: (i) the identification of the anthropogenic pressures; (ii) the quantification of their impacts on the ecosystems; (iii) the prioritization of these impacts. STARECAPMED also aims to confirm the relevance of the use of the Calvi Bay as a reference in the study of local and global pressures and the changes they may cause on the structure and the functioning of Mediterranean coastal ecosytems. [less ▲]

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See detailDGTs, a complementary tool towards more efficient biomonitoring practices
Richir, Jonathan ULiege; Lepoint, Gilles ULiege; Donnay, Annick et al

Conference (2015, October 01)

Among the diversity of contaminants, trace elements (TEs) remain of concern because of their persistence, their ability to accumulate in biota and their toxicity. The direct measurement of their dissolved ... [more ▼]

Among the diversity of contaminants, trace elements (TEs) remain of concern because of their persistence, their ability to accumulate in biota and their toxicity. The direct measurement of their dissolved concentrations only gives punctual and fluctuating information, and often remains below detection limits of analytical methods. The more appropriate use of sentinel organisms, or bioindicators, to monitor TEs has thus often been preferred in environmental surveys. The introduction of the diffusive gradients in thin films (DGTs) technique has however participated to progressively change this binary view - bioindicator vs water - of the coastal monitoring of TEs, and DGTs rapidly became a relevant complementary tool to bioindicators, has illustrated below. In the framework of the STARECAPMED project, the ecology and the ecotoxicology of TEs were studied in the seagrass Posidonia oceanica (L.) Delile and the mussel Mytilus galloprovincialis Lamarck, 1819. DGTs (free- and pore-water probes) were deployed before sampling of organisms. TEs were also analyzed in suspended matter (dissolved and suspended-particulate TE speciation). Studies were performed in the Calvi Bay (Corsica, France), northwestern Mediterranean. TE concentrations in organisms and suspended matter or in DGT resins were measured by DRC-ICP-MS after HNO3/H202 mineralization or after a 24h elution in HNO3 1M, respectively. (1) TE bioaccumulation was first seasonally studied in P. oceanica over 3 years. Dissolved TE concentrations monitored with DGTs were low to very low. TE bioaccumulation dynamics in P. oceanica could thus be linked to the natural physiological cycle of the plant, in clean environmental conditions. (2) To complement that field survey, isolated seagrasses were in situ contaminated with TEs at environmental relevant concentrations. Through the use of DGTs, TE uptake kinetics were modelled for seagrasses exposed to know bioavailable concentrations of contaminants, as were loss kinetics during the following depuration phase. The TE sequestration ability of a healthy P. oceanica meadow facing sudden trace metal contamination events could also be quantified. (3) The deployment of pore-water DGT probes in bare-sand or seagrass colonized sediments further showed that, through its stabilizing function of the seabed, P. oceanica maintained higher TE levels in the pore-water. P. oceanica meadows thus offer a significant “depuration-filtering” ecological service along highly anthropized Mediterranean coasts. M. galloprovincialis are widely used in large spatial scale coastal monitoring surveys. (4) The deployment of caged mussels together with DGTs showed that the little contaminated water body of the Calvi Bay was relatively homogenous. It also allowed to calculate TE bioaccumulation towards mussels in reference conditions, and to compare it to native mussel populations. (5) Finally, during a 5 months mussel caging survey, mussels and suspended matter were collected weekly to monthly, such as were deployed DGTs. The physiological status of mussels, the speciation of TEs between their dissolved and suspended-particulate phases, and their relative influence on TE bioaccumulation dynamics in mussels were investigated. In conclusion, these case studies properly demonstrate how DGT probes can be used as a relevant and complementary tool to bioindicators. Their concomitant use should therefore be privileged in monitoring surveys. [less ▲]

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See detailPlankton ecosystem response to the decadal variation of winter intensity in the Mediterranean Sea : a long-term study (1979-2014)
Goffart, Anne ULiege; Collignon, Amandine ULiege; Hecq, Jean-Henri ULiege et al

Poster (2015, October)

In the Mediterranean Sea, several studies with distinct data sets indicate that the pelagic ecosystem underwent periods of change in the late 1980s and in the early 2000s. Here we used a unique long-term ... [more ▼]

In the Mediterranean Sea, several studies with distinct data sets indicate that the pelagic ecosystem underwent periods of change in the late 1980s and in the early 2000s. Here we used a unique long-term time series of data collected in the well-preserved Bay of Calvi (Corsica island, Ligurian Sea, NW Mediterranean) from 1979 and 2014 to explore the synchrony between changes in environmental conditions and phyto- and zooplankton dynamics. We identified an almost decadal, long-term variability in winter intensity, with three distinct periods: the 1980s (1979-1988), the 1990s (1989-1998) and the 2000s (1999-2014), which were characterized by moderate, mild and highly variable winters, respectively. We pointed out how the decadal changes in winter intensity affected (i) the duration and intensity of phyto- and zooplankton blooms, (ii) the mean yearly biomasses, and (iii) the nature of the assemblages. High phyto- and zooplankton biomasses were observed in years characterized by moderate and severe winters, and low phyto- and zooplankton abundances were recorded in years with mild winters. Moderate/severe and mild winters were favorable for diatoms and gelatinous zooplankton, respectively. Focusing on meroplanktonic species, we explored ecological consequences of decadal variations observed in the Bay of Calvi for resource management. We highlighted parallelisms with other European seas. [less ▲]

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See detailPlankton ecosystem response to the decadal variation of winter intensity in the Mediterranean Sea : a long-term study (1979-2014)
Goffart, Anne ULiege; Collignon, Amandine ULiege; Hecq, Jean-Henri ULiege et al

Conference (2015, October)

In the Mediterranean Sea, several studies with distinct data sets indicate that the pelagic ecosystem underwent periods of change in the late 1980s and in the early 2000s. Here we used a unique long-term ... [more ▼]

In the Mediterranean Sea, several studies with distinct data sets indicate that the pelagic ecosystem underwent periods of change in the late 1980s and in the early 2000s. Here we used a unique long-term time series of data collected in the well-preserved Bay of Calvi (Corsica island, Ligurian Sea, NW Mediterranean) from 1979 and 2014 to explore the synchrony between changes in environmental conditions and phyto- and zooplankton dynamics. We identified an almost decadal, long-term variability in winter intensity, with three distinct periods: the 1980s (1979-1988), the 1990s (1989-1998) and the 2000s (1999-2014), which were characterized by moderate, mild and highly variable winters, respectively. We pointed out how the decadal changes in winter intensity affected (i) the duration and intensity of phyto- and zooplankton blooms, (ii) the mean yearly biomasses, and (iii) the nature of the assemblages. High phyto- and zooplankton biomasses were observed in years characterized by moderate and severe winters, and low phyto- and zooplankton abundances were recorded in years with mild winters. Moderate/severe and mild winters were favorable for diatoms and gelatinous zooplankton, respectively. Focusing on meroplanktonic species, we explored ecological consequences of decadal variations observed in the Bay of Calvi for resource management. We highlighted parallelisms with other European seas. [less ▲]

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See detailTrace metal speciation? An essential aspect of biomonitoring to avoid wrong conclusions
Richir, Jonathan ULiege; Lepoint, Gilles ULiege; Donnay, Annick et al

Poster (2015, September 29)

The Mediterranean mussel Mytilus galloprovincialis is widely used as a bioindicator species in active monitoring surveys. As a filter feeder artificially maintained in the water column, it bioaccumulates ... [more ▼]

The Mediterranean mussel Mytilus galloprovincialis is widely used as a bioindicator species in active monitoring surveys. As a filter feeder artificially maintained in the water column, it bioaccumulates trace metals from the surrounding water in their dissolved and particulate forms. However, most monitoring surveys don’t take into account that speciation aspect when studying trace metal accumulation kinetics in mussels. In the framework of the STARECAPMED project, we monitored trace metal concentrations in the flesh of mussels together with their “most bioavailable” dissolved and particulate fractions in the water column for almost 5 months (February-June 2011). Mussels were purchased from 2 little contaminated French shellfish farms (SARL Etang de Diane and ferme marine des Aresquiers), placed in several pouches to allow regular sampling, and immerged near the Oceanographic Research Station STARESO in the Calvi bay, northwestern Corsica. Mussels and water samples for suspended matter filtration were collected every week to two weeks, as were deployed DGTs. Seawater samples were filtered through 47 mm hydrophilic PTFE membrane filters with a 0.45 µm pore size until clogging. In the laboratory, mussel flesh and filters were digested in Teflon vessels with acids (HNO3/H202) in a closed microwave digestion lab station. DGT resins were eluted for 24h in 1.0 M HNO3. Trace metal concentrations (Cr, Mn, Co, Ni, Cu, Zn, Ag, Cd, Pb) were measured by DRC-ICP-MS. Analytical accuracy was checked by analyzing CRMs. All the studied metals except Pb and Zn were present in the water column to over 80% in their dissolved form. The contribution of the dissolved pathway was thus likely to be predominant in the oligotrophic Calvi bay. Dissolved trace metals showed little temporal variability of their levels, likely resulting from the integration over time of their levels in the DGT probes and the lack of seasonality of this fraction. In contrast, Zn showed great variability of its particulate fraction during the survey. Such temporal variability was also observed for Cr, more abundant in its particulate form at the end of the survey, and for Mn and Pb that conversely tended to decrease. The dynamic of trace metals in the mussel flesh is regulated by the environmental bioavailability of dissolved and particulate metals, the ecophysiological status of mussels and the trophic conditions of the water body. In the oligotrophic Calvi bay, showing background contamination levels by metals, the trophic conditions played a major role once out of the spring plankton bloom. It led to the increase of metal concentrations measured in the flesh of mussels undergoing starvation. However, some metals such as Cu and Co displayed only little temporal variations of their concentrations, these essential micronutrients being well regulated. The combined study of trace metal bioavailability and mussel ecophysiology in defined environmental conditions allows discriminating against biotic and abiotic factors regulating contaminant uptake in mussels, thus avoiding wrong conclusions about the observed dynamics of the studied contaminants. Mussels are a good proxy of coastal water quality, but their proper use notably requires adjustment of raw contaminant concentrations with trophic status of monitored sites. [less ▲]

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See detailSound production by dusky grouper Epinephelus marginatus at spawning aggregation sites
Bertucci, Frédéric; Lejeune, Pierre; Payrot, J et al

in Journal of Fish Biology (2015), 87(2), 400-421

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See detailSTARECAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) - Année 2014. Rapport de recherches.
Richir, Jonathan ULiege; Abadie, Arnaud ULiege; Binard, Marc ULiege et al

Report (2015)

La prise de conscience, par le grand public, de l'impact grandissant de l'homme sur l'océan est récente. Elle se traduit par une volonté politique sincère de correction par des mesures de protection, de ... [more ▼]

La prise de conscience, par le grand public, de l'impact grandissant de l'homme sur l'océan est récente. Elle se traduit par une volonté politique sincère de correction par des mesures de protection, de gestion et de développement durable. Ces politiques, et leurs conséquences économiques et sociétales lourdes, ne peuvent être acceptées que si les décisions se fondent sur des connaissances scientifiques incontestables et montrent des résultats scientifiquement prouvés. Par ailleurs, ces décisions doivent prendre en compte des impacts qui s'opèrent à des échelles de temps et d’espace très variables, de quelques heures à plusieurs dizaines d’années et de quelques mètres à plusieurs milliers de km. En termes politiques, l'information scientifique nécessaire à la prise de décision doit pouvoir couvrir les différentes échelles depuis le niveau local et régional, jusqu'à l'échelle nationale, européenne voire globale, et cela sur le plus long terme possible. Enfin, pour être complète, l'information scientifique sur les écosystèmes marins doit pouvoir répondre à trois questions objectives : (i) quel est l'état? (ii) quelle est l'évolution? (iii) quels sont les mécanismes et processus mis en jeux? et à une question plus prospective : (vi) que peux-t-on prévoir et comment agir? Le présent rapport ne peut pas, à lui seul, refléter toute la richesse du programme STARECAPMED. En 3 ans, STARECAPMED a généré plusieurs centaines de milliers de données nouvelles, ré-exploité plusieurs centaines de publications, rapports et autres enregistrements passés et présents. Le programme a aussi généré de nombreux documents, rapports et mémoires. Enfin, des publications internationales et des thèses de doctorat sont en cours de réalisation ou abouties. Afin de rester lisible, nous avons donc choisi de présenter ce rapport 2014 sous la forme de 12 exemples parmi les travaux en cours. Ces exemples sont traités selon un schéma identique en 4 points simples : (i) La présentation du cas d’étude dans le projet global ; (ii),Les approches innovatrices développées ; (iii),La présentation de résultats marquants ; (iv),Les délivrables de STARECAPMED pour les politiques publiques. [less ▲]

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