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Polystyrene microbeads modulate the energy metabolism of the marine diatom Chaetoceros neogracile Texto completo
2019
Seoane, Marta | González-fernández, Carmen | Soudant, Philippe | Huvet, Arnaud | Esperanza, Marta | Cid, Ángeles | Paul-pont, Ika
Due to the growing concern about the presence of microplastics (MP) in the environment, the number of studies evaluating the toxicity of these small persistent particles on different marine species has increased in recent years. Few studies have addressed their impact on marine phytoplankton, a subject of great concern since they are primary producers of the aquatic food web. The aim of this study is to unravel the cytotoxicity of 2.5 μg mL−1 unlabelled amino-modified polystyrene beads of different sizes (0.5 and 2 μm) on the marine diatom Chaetoceros neogracile. In addition to traditional growth and photosynthesis endpoints, several physiological and biochemical parameters were monitored every 24 h in C. neogracile cells by flow cytometry during their exponential growth (72 h). Dynamic Light Scattering measurements revealed the strong aggregation and the negative charge of the beads assayed in the culture medium, which seemed to minimize particle interaction with cells and potentially associated impacts. Indeed, MP were not attached to the microalgal cell wall, as evidenced by scanning electron micrographs. Cell growth, morphology, photosynthesis, reactive oxygen species levels and membrane potential remained unaltered. However, exposure to MP significantly decreased the cellular esterase activity and the neutral lipid content. Microalgal oil bodies could serve as an energy source for maintaining a healthy cellular status. Thus, MP-exposed cells modulate their energy metabolism to properly acclimate to the stress conditions.
Mostrar más [+] Menos [-]Comparison in the response of three European Gammarid species exposed to the growth regulator insecticide fenoxycarb Texto completo
2019
Arambourou, Hélène | Vulliet, Emmanuelle | Danièle, Gaëlle | Noury, Patrice | Delorme, Nicolas | Abbaci, Khedidja | Forcellini, Maxence | Tutundjian, Renaud | Barata, Carlos | RiverLy (UR Riverly) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | ISA-TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) | Institute of Environmental Assessment and Water Research (IDAEA) ; Consejo Superior de Investigaciones Cientificas = Spanish National Research Council (CSIC) | French Ec2co program
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Growth regulator insecticides with juvenoid activity can affect the development and reproduction of non-target organisms such as crustaceans. In this perspective, our previous studies revealed deleterious effects of the juvenoid fenoxycarb at 5 µg L
Mostrar más [+] Menos [-]Does water temperature influence the distribution and elimination of perfluorinated substances in rainbow trout (Oncorhynchus mykiss)? Texto completo
2019
Vidal, Alice | Lafay, Florent | Danièle, Gaëlle | Vulliet, Emmanuelle | Rochard, Eric | Garric, Jeanne | Babut, Marc | RiverLy (UR Riverly) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | ISA-TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Perfluorinated and polyfluorinated substances (PFASs) are widely found in freshwater ecosystems because of their resistance to degradation and their ability to accumulate in aquatic organisms. While water temperature controls many physiological processes in fish, knowledge of the effects of this factor on PFAS toxicokinetic is still limited. This study presents experimental results of internal distribution and elimination rates of two perfluorinated acid compounds, namely perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS) in adult rainbow trout (Oncorhynchus mykiss) exposed to three temperatures. Dietary exposure experiments were conducted at 7 °C, 11 °C, and 19 °C and liver, blood, muscle, brain, and kidney were sampled for analysis. PFOS concentrations were comparable to or exceeded those of PFHxS, while PFHxS was eliminated faster than PFOS, whatever the temperature. Internal distribution changed significantly for both substances when fish were exposed to a range of temperatures from 7 to 19 °C. Indeed, PFOS and PFHxS relative distribution increased in blood, liver, and brain while they decreased in muscle when the water temperature rose. The water temperature variation affected the elimination half-lives, depending on the substances and organs.
Mostrar más [+] Menos [-]Organic micropollutants' distribution within sludge organic matter fractions explains their dynamic during sewage sludge anaerobic digestion followed by composting Texto completo
2019
Aemig, Quentin | Doussiet, Nicolas | Danel, Alice | Delgenes, Nadine | Jimenez, Julie | Houot, Sabine | Patureau, Dominique | Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE) ; Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | ADEME (PhD Grant); AFB (Project n°Action 12-5-1)
International audience | The simultaneous fate of organic matter and 4 endocrine disruptors (3 polycyclic aromatic hydrocarbons (PAHs) (fluoranthene, benzo(b)fluoranthene, and benzo(a)pyrene) and nonylphenols (NP)) was studied during the anaerobic digestion followed by composting of sludge at lab-scale. Sludge organic matter was characterized, thanks to chemical fractionation and 3D fluorescence deciphering its accessibility and biodegradability. Total chemical oxygen demand (COD) removal was 41% and 56% during anaerobic digestion and composting, respectively. 3D fluorescence highlighted the quality changes of organic matter. During continuous anaerobic digestion, organic micropollutants' removal was 22±14%, 6±5%, 18±9%, and 0% for fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, and nonylphenols, respectively. Discontinuous composting allowed to go further on the organic micropollutants' removal as 34±8%, 31±20%, 38±10%, and 52±6% of fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, and nonylphenols were dissipated, respectively. Moreover, the accessibility of PAH and NP expressed by their presence in the various sludge organic matter fractions and its evolution during both treatments was linked to both the quality evolution of the organic matter and the physicochemical properties of the PAH and NP; the presence in most accessible fractions explained the amount of PAH and NP dissipated.
Mostrar más [+] Menos [-]Intermittent flux from a sand filter for household wastewater and integrated solute transfer to the vadose zone Texto completo
2019
Nasri, Behzad | Fouché, Olivier | Laboratoire Géomatique et foncier (GeF) ; Conservatoire National des Arts et Métiers [Cnam] (Cnam) | Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris) ; Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)
International audience
Mostrar más [+] Menos [-]Comparison in the response of three European Gammarid species exposed to the growth regulator insecticide fenoxycarb Texto completo
2019
Arambourou, Hélène | Vulliet, Emmanuelle | Danièle, Gaëlle | Noury, Patrice | Delorme, Nicolas | Abbaci, Khedidja | Forcellini, Maxence | Tutundjian, Renaud | Barata, Carlos | RiverLy - Fonctionnement des hydrosystèmes ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | ISA-TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Institute of Environmental Assessment and Water Research (IDAEA) ; Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC) | French Ec2co program
Comparison in the response of three European Gammarid species exposed to the growth regulator insecticide fenoxycarb Texto completo
2019
Arambourou, Hélène | Vulliet, Emmanuelle | Danièle, Gaëlle | Noury, Patrice | Delorme, Nicolas | Abbaci, Khedidja | Forcellini, Maxence | Tutundjian, Renaud | Barata, Carlos | RiverLy - Fonctionnement des hydrosystèmes ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | ISA-TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé ; Institut des Sciences Analytiques (ISA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Institute of Environmental Assessment and Water Research (IDAEA) ; Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC) | French Ec2co program
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Growth regulator insecticides with juvenoid activity can affect the development and reproduction of non-target organisms such as crustaceans. In this perspective, our previous studies revealed deleterious effects of the juvenoid fenoxycarb at 5 µg L
Mostrar más [+] Menos [-]Comparison in the response of three European Gammarid species exposed to the growth regulator insecticide fenoxycarb | Comparison of the response to growth regulator insecticide fenoxycarb exposure in three European Gammaridae species Texto completo
2019
Arambourou, Hélène | Vulliet, Emmanuelle | Daniele, Gaëlle | Noury, Patrice | Delorme, Nicolas | Abbaci, Khédidja Tair | Forcellini, Maxence | Tutundjian, Renaud | Barata Martí, Carlos | Barata Martí, Carlos [0000-0002-3360-0729]
Growth regulator insecticides with juvenoid activity can affect the development and reproduction of non-target organisms such as crustaceans. In this perspective, our previous studies revealed deleterious effects of the juvenoid fenoxycarb at 5 μg L −1 on the embryogenesis and at 50 μg L −1 on the reproductive behavior of the amphipod Gammarus fossarum. In the present study, to determine whether data generated with one amphipod species can be extended to other gammarid species, we tested the effects of a 5 μg L −1 fenoxycarb exposure on three European amphipod species: G. fossarum, Gammarus roeseli, and Echinogammarus longisetosus. We exposed individually 60 freshly fertilized females to fenoxycarb throughout the entire oogenesis/embryogenesis cycle (i.e., 19 days). In newborn individuals from exposed embryos, we measured both pigmentation and lipid reserve impairments while in exposed females, we observed reproductive behavior. At 5 μg L −1 fenoxycarb, reproductive behavior was only altered in G. fossarum. This study demonstrates the variability of the toxic response among the three gammaridae species, underlining the need for acquiring data with a broad phylogenetic representation to better predict toxic effects on freshwater ecosystems. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature. | This research was financially supported by the French Ec2co program. | Peer reviewed
Mostrar más [+] Menos [-]Environmental variations mediate duckweed (Lemna minor L.) sensitivity to copper exposure through phenotypic plasticity Texto completo
2019
Roubeau Dumont, Eva | Larue, Camille | Pujol, Benoît | Lamaze, Thierry | Elger, Arnaud | Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT) | Evolution et Diversité Biologique (EDB) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) | Centre de recherches insulaires et observatoire de l'environnement (CRIOBE) ; Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Centre d'études spatiales de la biosphère (CESBIO) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Environmental variations mediate duckweed (Lemna minor L.) sensitivity to copper exposure through phenotypic plasticity Texto completo
2019
Roubeau Dumont, Eva | Larue, Camille | Pujol, Benoît | Lamaze, Thierry | Elger, Arnaud | Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT) | Evolution et Diversité Biologique (EDB) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) | Centre de recherches insulaires et observatoire de l'environnement (CRIOBE) ; Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Centre d'études spatiales de la biosphère (CESBIO) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Environmentally mediated sensitivity of Lemna minor to copper (Cu) was evaluated for the first time in three experiments: the effects of two levels of nutrient concentration, light irradiance or Cu pre-exposure were tested. Various Cu concentrations (ranging from 0.05 to 0.25 mg/L) were used to assess the sensitivity of L. minor to this metal, using one common strain previously acclimatized to two different levels of light intensity, nutrient enrichment and Cu pre-exposure. Our results showed a phenotypic plastic response of the relative growth rates based on frond number and fresh mass production, and maximum quantum yield of photosystem II (Fv/Fm). Growth was affected by the three environmental conditions both prior and during Cu exposure, whereas Fv/Fm was mostly affected during Cu exposure. Copper significantly influenced all the parameters measured in the three experiments. Environmental conditions significantly modified L. minor sensitivity to Cu in all experiments, with up to twofold difference depending on the treatment. Growth rate was the parameter that was most impacted. Our study revealed for the first time the existence of phenotypic plasticity in L. minor sensitivity to chemical contamination, and implies that environmental context needs to be taken into account for a relevant risk assessment.
Mostrar más [+] Menos [-]Environmental variations mediate duckweed (Lemna minor L.) sensitivity to copper exposure through phenotypic plasticity Texto completo
2019
Roubeau Dumont, Eva | Larue, Camille | Pujol, Benoît | Lamaze, Thierry | Elger, Arnaud
Environmentally mediated sensitivity of Lemna minor to copper (Cu) was evaluated for the first time in three experiments: the effects of two levels of nutrient concentration, light irradiance or Cu pre-exposure were tested. Various Cu concentrations (ranging from 0.05 to 0.25 mg/L) were used to assess the sensitivity of L. minor to this metal, using one common strain previously acclimatized to two different levels of light intensity, nutrient enrichment and Cu pre-exposure. Our results showed a phenotypic plastic response of the relative growth rates based on frond number and fresh mass production, and maximum quantum yield of photosystem II (Fᵥ/Fₘ). Growth was affected by the three environmental conditions both prior and during Cu exposure, whereas Fᵥ/Fₘ was mostly affected during Cu exposure. Copper significantly influenced all the parameters measured in the three experiments. Environmental conditions significantly modified L. minor sensitivity to Cu in all experiments, with up to twofold difference depending on the treatment. Growth rate was the parameter that was most impacted. Our study revealed for the first time the existence of phenotypic plasticity in L. minor sensitivity to chemical contamination, and implies that environmental context needs to be taken into account for a relevant risk assessment.
Mostrar más [+] Menos [-]Influence of the residence time of street trees and their soils on trace element contamination in Paris (France) Texto completo
2019
Quenea, Katell | Andrianjara, Iry | Rankovic, Aleksandar | Gan, Erika | Aubry, Emmanuel | Lata, Jean-Christophe | Barot, Sébastien | Castrec-Rouelle, Maryse | Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS) | Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris) ; Institut National de la Recherche Agronomique (INRA)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Agronomie de la ville de Paris ; Direction des Espaces Verts et de l'Environnement (DEVE) | Institut du Développement Durable et des Relations Internationales (IDDRI) ; Institut d'Études Politiques [IEP] - Paris | Tomsk Polytechnic University [Russie] (UPT) | Ile-de-France region (R2DS); GIS "Climate, Environment, Society" (CCTV2 Project); PIR IngEcoTech (IESUM project); Sorbonne Universities (Dens' project, Convergences program)
International audience | With the actual increasing interest for urban soils, the evaluation of soil contamination by trace elements and the dynamics of this contamination appear mandatory to preserve plant and thereby human health. Street trees and the associated soil placed in pits located nearby roads could represent convenient indicators of urban and vehicle traffic influences on soils and plants. However, data on these soils remain scarce, many studies investigating park soils rather than street tree soils. Furthermore, trace elements could be one of the main factors causing the observed urban tree decline, while practitioners more and more question the possible reuse of these soils after the death of trees as well as tree litter collected in the streets. We evaluated the contamination in anthropogenic trace elements (TE), namely Zn, Pb, and Cd, of street trees (Tilia tomentosa) and their soils distributed all over Paris (France). Street tree soils are imported from rural areas at the plantation of each new tree so that tree age corresponds to the time of residence of the soil within an urban environment allowing the evaluation of temporal trends on TE concentration in soils and trees. The TE concentration revealed an important soil pollution, especially for the older soils (mean age of 80 years old). The consideration of the residence time of trees and soils in an urban environment evidenced an accumulation of Zn and Pb (ca. 4.5 mg kg−1 year−1 and 4 mg kg−1 year−1 for Zn and Pb, respectively). However, leaf concentrations in TE were low and indicate that soil-root transfer was not significant compared to the contamination by atmospheric deposition. These results underlined the necessity to deepen the evaluation of the recycling of urban soils or plants submitted to urban contamination.
Mostrar más [+] Menos [-]Patterns of trace metal bioaccumulation and trophic transfer in a phytoplankton-zooplankton-small pelagic fish marine food web Texto completo
2019
Chouvelon, Tiphaine | Strady, Emilie | Harmelin-vivien, Mireille | Radakovitch, Olivier | Brach-papa, Christophe | Crochet, Sylvette | Knoery, Joel | Rozuel, Emmanuelle | Thomas, Bastien | Tronczynski, Jacek | Chiffoleau, Jean-francois
Trace metal contamination in the European sardine and anchovy food web was investigated in the Gulf of Lions, NW Mediterranean Sea, including seawater and size fractions of plankton. The results highlighted: i) higher and more variable concentrations in the smaller plankton size classes for all metals except cadmium; ii) higher concentrations in anchovy versus sardine for all elements except lead; iii) different patterns of metal bioaccumulation through the food web: cobalt, nickel, copper, silver, lead and zinc displayed continuously decreasing concentrations (with the exception of increased zinc in fish only), while mercury concentrations dropped considerably in larger plankton size classes and rose significantly in fish. Lastly, cadmium concentrations were found to be highest in intermediate plankton size classes, with very low levels in fish. The need to efficiently characterize the biological composition of plankton in order to fully identify its role in the mobilization and transfer of metals was highlighted.
Mostrar más [+] Menos [-]Large impact of Stokes drift on the fate of surface floating debris in the South Indian Basin Texto completo
2019
Dobler, Delphine | Huck, Thierry | Maes, Christophe | Grima, Nicolas | Blanke, Bruno | Martinez, Elodie | Ardhuin, Fabrice
In the open ocean, floating surface debris such as plastics concentrate in five main accumulation zones centered around 30° latitude, far from highly turbulent areas. Using Lagrangian advection of numerical particles by surface currents from ocean model reanalysis, previous studies have shown long-distance connection from the accumulation zones of the South Indian to the South Pacific oceans. An important physical process affecting surface particles but missing in such analyses is wave-induced Stokes drift. Taking into account surface Stokes drift from a wave model reanalysis radically changes the fate of South Indian particles. The convergence region moves from the east to the west of the basin, so particles leak to the South Atlantic rather than the South Pacific. Stokes drift changes the South Indian sensitive balance between Ekman convergence and turbulent diffusion processes, inducing either westward entrainment in the north of the accumulation zone, or eastward entrainment in the south.
Mostrar más [+] Menos [-]