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A study of trophic structure, physiological condition and mercury biomagnification in swordfish (Xiphias gladius): Evidence of unfavourable conditions for the swordfish population in the Western Mediterranean Full text
2022
Biton-Porsmoguer, Sebastián | Bănaru, Daniela | Harmelin-Vivien, Mireille | Béarez, Philippe | Bouchoucha, Marc | Marco-Miralles, Françoise | Marquès, Montse | Lloret, Josep
A study of trophic structure, physiological condition and mercury biomagnification in swordfish (Xiphias gladius): Evidence of unfavourable conditions for the swordfish population in the Western Mediterranean Full text
2022
Biton-Porsmoguer, Sebastián | Bănaru, Daniela | Harmelin-Vivien, Mireille | Béarez, Philippe | Bouchoucha, Marc | Marco-Miralles, Françoise | Marquès, Montse | Lloret, Josep
International audience | Studies integrating trophic ecology, physiological condition and accumulation of heavy metals in top predators, such as swordfish, are needed to better understand the links between them and the risk to humans associated with consumption of these fish. This research focuses on the swordfish of the Catalan Sea and follows a multi method approach that considers their diet, their liver lipid content, and mercury accumulation in their bodies as well as in their prey. The aim is to highlight the links between trophic ecology, physiology (fish condition), and ecotoxicology. Results indicate that poor condition of swordfish based on size and the levels of lipid in the liver, and the high Hg levels accumulated to the trophic web (particularly from cephalopods) may indicate potential unfavourable feeding and reproduction conditions for swordfish in the NW Mediterranean and that this warrants further investigation.
Show more [+] Less [-]A study of trophic structure, physiological condition and mercury biomagnification in swordfish (Xiphias gladius): Evidence of unfavourable conditions for the swordfish population in the Western Mediterranean Full text
2022
Biton-Porsmoguer, Sebastián | Bănaru, Daniela | Harmelin-Vivien, M. L. (Mireille L.) | Béarez, Philippe | Bouchoucha, Marc | Marco-Miralles, Françoise | Marquès, Montse | Lloret, Josep
Studies integrating trophic ecology, physiological condition and accumulation of heavy metals in top predators, such as swordfish, are needed to better understand the links between them and the risk to humans associated with consumption of these fish. This research focuses on the swordfish of the Catalan Sea and follows a multi method approach that considers their diet, their liver lipid content, and mercury accumulation in their bodies as well as in their prey. The aim is to highlight the links between trophic ecology, physiology (fish condition), and eco-toxicology. Results indicate that poor condition of swordfish based on size and the levels of lipid in the liver, and the high Hg levels accumulated to the trophic web (particularly from cephalopods) may indicate potential unfavourable feeding and reproduction conditions for swordfish in the NW Mediterranean and this warrants further investigation.
Show more [+] Less [-]A study of trophic structure, physiological condition and mercury biomagnification in swordfish (Xiphias gladius): Evidence of unfavourable conditions for the swordfish population in the Western Mediterranean Full text
2022
Biton-porsmoguer, Sebastián | Bănaru, Daniela | Harmelin-vivien, Mireille | Béarez, Philippe | Bouchoucha, Marc | Marco-miralles, Francoise | Marquès, Montse | Lloret, Josep
Studies integrating trophic ecology, physiological condition and accumulation of heavy metals in top predators, such as swordfish, are needed to better understand the links between them and the risk to humans associated with consumption of these fish. This research focuses on the swordfish of the Catalan Sea and follows a multi method approach that considers their diet, their liver lipid content, and mercury accumulation in their bodies as well as in their prey. The aim is to highlight the links between trophic ecology, physiology (fish condition), and eco-toxicology. Results indicate that poor condition of swordfish based on size and the levels of lipid in the liver, and the high Hg levels accumulated to the trophic web (particularly from cephalopods) may indicate potential unfavourable feeding and reproduction conditions for swordfish in the NW Mediterranean and this warrants further investigation.
Show more [+] Less [-]A study of trophic structure, physiological condition and mercury biomagnification in swordfish (Xiphias gladius): Evidence of unfavourable conditions for the swordfish population in the Western Mediterranean Full text
2022
Biton-Porsmoguer, Sebastián | Banaru, Daniela | Harmelin-Vivien, Mirelle | Béarez, Philippe | Bouchoucha, Marc | Marco-Miralles, Françoise | Marquès, Montse | Lloret, Josep
10 pages, 4 figures, 4 tables, supplementary data https://doi.org/10.1016/j.marpolbul.2022.113411 | Studies integrating trophic ecology, physiological condition and accumulation of heavy metals in top predators, such as swordfish, are needed to better understand the links between them and the risk to humans associated with consumption of these fish. This research focuses on the swordfish of the Catalan Sea and follows a multi method approach that considers their diet, their liver lipid content, and mercury accumulation in their bodies as well as in their prey. The aim is to highlight the links between trophic ecology, physiology (fish condition), and eco-toxicology. Results indicate that poor condition of swordfish based on size and the levels of lipid in the liver, and the high Hg levels accumulated to the trophic web (particularly from cephalopods) may indicate potential unfavourable feeding and reproduction conditions for swordfish in the NW Mediterranean and this warrants further investigation | Peer reviewed
Show more [+] Less [-]Impact of returning scientific cruises and prolonged on-site presence on litter abundance at the deep-sea nodule fields in the Peru Basin Full text
2022
Cuvelier, Daphne | Ramalho, Sofia P | Purser, Autun | Haeckel, Matthias
Marine litter can be found along coasts, continental shelves and slopes, down into the abyss. The absence of light, low temperatures and low energy regimes characterising the deeper habitats ensure the persistence of litter over time. Therefore, manmade items within the deep sea will likely accumulate to increasing quantities. Here we report the litter abundance encountered at the Pacific abyssal nodule fields from the Peru Basin at 4150 m depth. An average density of 2.67 litter items/ha was observed. Litter composed of plastic was the most abundant followed by metal and glass. At least 58 % of the items observed could be linked to the research expeditions conducted in the area and appeared to be mostly accidental disposals from ships. The data gathered was used to address temporal trends in litter abundance as well as the impact of human on-site presence and return cruises in the context of future deep-sea mining efforts.
Show more [+] Less [-]The multilevel antibiotic-induced perturbations to biological systems Early-life exposure induces long-lasting damages to muscle structure and mitochondrial metabolism in flies Full text
2018
Renault, David | Yousef, Hesham | Mohamed, Amr A
International audience | Antibiotics have been increasingly used over the past decades for human medicine, food-animal agriculture, aquaculture, and plant production. A significant part of the active molecules of antibiotics can be released into the environment, in turn affecting ecosystem functioning and biogeochemical processes. At lower organizational scales, these substances affect bacterial symbionts of insects, with negative consequences on growth and development of juveniles, and population dynamics. Yet, the multiple alterations of cellular physiology and metabolic processes have remained insufficiently explored in insects. We evaluated the effects of five antibiotics with different mode of action, i.e. ampicillin, cefradine, chloramphenicol, cycloheximide, and tetracycline, on the survival and ultrastructural organization of the flight muscles of newly emerged blow flies Chrysomya albiceps. Then, we examined the effects of different concentrations of antibiotics on mitochondrial protein content, efficiency of oxidative phosphorylation, and activity of transaminases (Glutamate oxaloacetate transaminase and glutamate pyruvate transaminase) and described the cellular metabolic perturbations of flies treated with antibiotics. All antibiotics affected the survival of the insects and decreased the total mitochondrial protein content in a dose-dependent manner. Ultrastructural organization of flight muscles in treated flies differs dramatically compared to the control groups and severe pathological damages/structures disorganization of mitochondria appeared. The activities of mitochondrial transaminases significantly increased with increased antibiotic concentrations. The oxidation rate of pyruvate + proline from isolated mitochondria of the flight muscles of 1-day-old flies was significantly reduced at high doses of antibiotics. In parallel, the level of several metabolites, including TCA cycle intermediates, was reduced in antibiotics-treated flies. Overall, antibiotics provoked a system-wide alteration of the structure and physiology of flight muscles of the blow fly Ch. albiceps, and may have fitness consequences at the organism level. Environmental antibiotic pollution is likely to have unwanted cascading ecological effects of insect population dynamics and community structure.
Show more [+] Less [-]Remediation of PAH-contaminated soils: Experimental analysis and modeling of hydrodynamics and mass transfer in a soil-slurry bioreactor. Full text
2016
Pino Herrera, Douglas Oswaldo | Pechaud, Yoan | Huguenot, David | Fayolle, Y. | Pageot, S. | Oturan, Nihal | Esposito, Giovanni | Van Hullebusch, Eric D. | Oturan, Mehmet A.
Zeolitic tuffs for acid mine drainage (AMD) treatment in Ecuador: breakthrough curves for Mn2+, Cd2+, Cr3+, Zn2+ and Al3+. DOI: 10.1007/s11356-016-8177-9 Full text
2016
Buenaño Guerra, Xavier | Canoira López, Laureano | Martín Sánchez, Domingo Alfonso | Costafreda Mustelier, Jorge Luis
Zeolitic tuff constitutes a technical and economical feasible alternative to manage acidic waters in initial phases of generation. A study of cation exchange with two zeolitic tuffs from Ecuador and one from Cuba has been conducted using breakthrough curve methodology. Cations Mn2+, Cd2+, Cr3+, Zn2+, and Al3+ have been chosen owing to their presence in underground water in exploration activities (decline development) in Fruta del Norte (Ecuador). Zeolites characterized by X-ray diffraction and thermal stability after heating overnight as heulandites show a similar exchange behavior for the five cations studied. The clinoptilolite sample Tasajeras shows a relevant cation exchange performance expressed in the important increment of spatial time to reach the breakthrough point in comparison with heulandite samples. The maximum length of unused beds was found for Cr3+ and Zn2+ cations showing, therefore, a lower adsorption performance in relation with Mn2+ and Cd2+. A final disposal method of metal-loaded zeolites with cement is proposed.
Show more [+] Less [-]Brown rust disease control in winter wheat: II. Exploring the optimization of fungicide sprays through a decision support system Full text
2014
El Jarroudi, Moussa | Kouadio, Amani Louis | Giraud, Frédéric | Delfosse, Philippe | Tychon, Bernard | Centre de recherche Publique Gabriel Lippmann
peer reviewed | A decision support system (DSS) involving an approach for predicting wheat leaf rust (WLR) infection and progress based on night weather variables (i.e., air temperature, relative humidity, and rainfall) and a mechanistic model for leaf emergence and development simulation (i.e., PROCULTURE) was tested in order to schedule fungicide time spray for controlling leaf rust progress in wheat fields. Experiments including a single fungicide treatment based upon the DSS along with double and triple treatment were carried out over the 2007–2009 cropping seasons in four representative Luxembourgish wheat field locations. The study showed that the WLR occurrences and severities differed according to the site, cultivar, and year. We also found out that the single fungicide treatment based on the DSS allowed a good protection of the three upper leaves of susceptible cultivars in fields with predominant WLR occurrences. The harvested grain yield was not significantly different from that of the double and triple fungicide-treated plots (P < 0.05). Such results could serve as basis or be coupled to cost-effective and environmentally friendly crop management systems in operational context.
Show more [+] Less [-]Changement de productivité des forêts: diagnostics et théories Full text
2006
Houllier, François | Bontemps, Jean-Daniel | Dhôte, Jean-François
Changement de productivité des forêts: diagnostics et théories Full text
2006
Houllier, François | Bontemps, Jean-Daniel | Dhôte, Jean-François
Les changements de productivité des forêts ont été étudiés intensément à partir des années 1990, à la suite des événements relatifs au dépérissement des forêts européennes. Dans cette contribution, on analyse les problèmes méthodologiques soulevés par ce type d'étude, les sources de données disponibles pour l'analyse, et les éléments de diagnostic acquis sur plusieurs espèces forestières du territoire français. Les implications pour le cadre théorique qui prévalait dans les années 1980 concernant la productivité des peuplements forestiers sont enfin discutées. problèmes méthodologiques, sources de données, cadre théorique, éléments du diagnostic
Show more [+] Less [-]Changement de productivité des forêts: diagnostics et théories Full text
2006
Houllier, François | Bontemps, Jean-Daniel | Dhôte, Jean-François | Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [Occitanie]) | Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech
International audience | Les changements de productivité des forêts ont été étudiés intensément à partir des années 1990, à la suite des événements relatifs au dépérissement des forêts européennes. Dans cette contribution, on analyse les problèmes méthodologiques soulevés par ce type d'étude, les sources de données disponibles pour l'analyse, et les éléments de diagnostic acquis sur plusieurs espèces forestières du territoire français. Les implications pour le cadre théorique qui prévalait dans les années 1980 concernant la productivité des peuplements forestiers sont enfin discutées. problèmes méthodologiques, sources de données, cadre théorique, éléments du diagnostic
Show more [+] Less [-]Investigations of nitrogen fluxes and pools model approaches and results
2002
Herman, F. (Institute fur Immissionsforschung und Forstchemie, Vienna (Austria)) | Smidt, S. | Englisch, M. | Feichtinger, F. | Gerzabek, M. | Haberhauer, G. | Jandl, R. | Kalina, M. | Zechmeister-Boltenstern, S.
In the North Tyrolean Limestone Alps a site was investigated over a four-year period (1998-2001) in order to assess the nitrogen saturation status, the nitrogen budget (quantification of the net uptake of nitrogen by the canopy and of the nitrogen mineralization, nitrogen uptake from roots and N2O emission rates, proof of the origin of nitrate in the soil water with stable isotope analyses, and the effects of the actual nitrogen input on ground water quality. The main goals were to quantify the nitrogen input rate, the nitrogen pools in above-ground and below-ground compartments, nitrogen turnover processes in the soil as well as the output into the groundwater and into the atmosphere. The findings are based on continuous and discontinuous field measurements as well as on model results
Show more [+] Less [-]Growth responses of two silver birch clones to elevated CO2 and O3 during three years of exposure in OTCs
2002
Riikonen, J. (Finnish Forest Research Institute, Suonenjoki (Finland). Suonenjoki Research Station) | Lindsberg, M. M. | Peltonen, P. | Oksanen, E. | Syrjala, L. | Holopainen, T. | Vapaavuori, E.
Atmospheric carbon dioxide (CO2) and ozone (O3) are increasing by 1-2% per year and are expected to double by the year 2100 compared to the end of the last millennium. Carbon dioxide at twice the current atmospheric concentrations has the potential to increase the productivity of forest trees while increasing ozone is expected to cause significant reductions in growth. The present study was undertaken to investigate the effects of CO2 and O3, singly or in combination, on growth and allocation of two European silver birch (Betula pendula Roth) clones under field conditions to verify the future predicitons in regard to silver birch. Our data show that growth of clone 80 was benefitted by ambient CO2 singly and in combination with ambient O3. Clone 4 was more responsive to ambient O3 than clone 80 which is opposite to results from previous pot experiments with these clones
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