Consulta: creatorFacets:"Dupraz, Valentin"
Registros recuperados: 8
Data/hora: 07/06/2024 01:13:49

Outil de la valorisation des données de l’environnement littoral pour la Directive Cadre Européenne sur l’eau (DCE). Atlas en ligne interactif : présentation de l’outil, fonctionnement du module d’administration
Provedor de dados: 5
Autores: Grouhel-pellouin, Anne; Faure, Sandra; Oger-jeanneret, Helene; Dupraz, Valentin.
La diffusion et la valorisation des résultats des suivis DCE passe notamment par la mise en ligne des informations régulièrement mises à jour concernant les réseaux de surveillance, les masses d’eau et les résultats de la surveillance. L’outil spécifiquement dédié à ces mises à jour a été développé par la société Alkante. Les instructions pour l’utilisation de cet outil dans chaque bassin, remises à jour des évolutions de 2014, sont présentées ici.
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00266/37737/35753.pdf

Demonstrating the need for chemical exposure characterisation in a microplate test system: Toxicity screening of sixteen pesticides on two marine microalgae
Provedor de dados: 5
Autores: Dupraz, Valentin; Stachowski-haberkorn, Sabine; Wicquart, Jérémy; Tapie, Nathalie; Budzinski, Hélène; Akcha, Farida.
Pesticides used in viticulture create a potential risk for the aquatic environment due to drift during application, runoff and soil leaching. The toxicity of sixteen pesticides and one metabolite were evaluated on the growth of two marine microalgae, Tisochrysis lutea and Skeletonema marinoi, in 96-h exposure assays conducted in microplates. For each substance, concentrations of stock solutions were analytically measured and abiotic assays were performed to evaluate the chemical stability of pesticides in microplates. For two chemicals, microalgae exposures were run simultaneously in microplates and culture flasks to compare EC50 calculated from the two exposure systems. Results from chemical analyses demonstrated the low stability of hydrophobic...
Tipo: Text
Palavras-chave: Microalgae; Microplates; Screening; Pesticides; Toxicity; Exposure characterisation.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00474/58558/61113.pdf

Microalgal sensitivity varies between a diuron-resistant strain and two wild strains when exposed to diuron and irgarol, alone and in mixtures
Provedor de dados: 5
Autores: Dupraz, Valentin; Coquille, Nathalie; Menard, Dominique; Sussarellu, Rossana; Haugarreau, Larissa; Stachowski-haberkorn, Sabine.
A wild strain of Chaetoceros calcitrans and wild and diuron-resistant strains of Tetraselmis suecica, were exposed to the PSII inhibitor herbicides diuron and irgarol, individually and in mixtures. The effects of three concentrations of diuron and irgarol and four binary mixtures were evaluated on doubling time, relative reactive oxygen species and lipid content by flow cytometry, and on photosynthetic efficiency by pulse amplitude modulated fluorescence.  In both wild strains, significant effects were observed for each molecule at the highest concentration tested: at irgarol 0.5 μg L−1, C. calcitrans was shown to be more sensitive than T. suecica (+52% and +19% in doubling time, respectively), whereas at diuron 5 μg L−1, T. suecica was more affected...
Tipo: Text
Palavras-chave: Microalgae; Herbicides; Antifouling; Irgarol; Diuron; Diuron resistance.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00319/43047/42658.pdf

Combined effects of antifouling biocides on the growth of three marine microalgal species
Provedor de dados: 5
Autores: Dupraz, Valentin; Stachowski-haberkorn, Sabine; Menard, Dominique; Limon, Gwendolina; Akcha, Farida; Budzinski, Helene; Cedergreen, Nina.
The toxicity of the antifouling compounds diuron, irgarol, zinc pyrithione (ZnPT), copper pyrithione (CuPT) and copper was tested on the three marine microalgae Tisochrysis lutea, Skeletonema marinoi and Tetraselmis suecica. Toxicity tests based on the inhibition of growth rate after 96-h exposure were run using microplates. Chemical analyses were performed to validate the exposure concentrations and the stability of the compounds under test conditions. Single chemicals exhibited varying toxicity depending on the species, irgarol being the most toxic chemical and Cu the least toxic. Selected binary mixtures were tested and the resulting interactions were analyzed using two distinct concentration-response surface models: one using the concentration addition...
Tipo: Text
Palavras-chave: Diuron; Irgarol; Pyrithione; Copper; Microbial ecotoxicology; Mixture model.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00445/55695/57362.pdf

Directive cadre sur l’eau. Bassin Loire-Bretagne. Contrôle de surveillance dans les masses d’eau côtières et de transition. Actions menées par Ifremer en 2013
Provedor de dados: 5
Autores: Grouhel-pellouin, Anne; Dupraz, Valentin; Allenou, Jean-pierre; Chauvin, Jacky; Cheve, Julien; Collin, Karine; Dagault, Francoise; Derrien, Annick; Doner, Anne; Duval, Audrey; Faure, Sandra; Fortune, Mireille; Gabellec, Raoul; Legendre, Aurelie; Lejolivet, Aurore; Le Merrer, Yoann; Retho, Michael; Robert, Serge; Truquet, Isabelle.
Le contrôle de surveillance 2013 pour la DCE appliquée dans les eaux littorales de Loire Bretagne a porté sur les 25 masses d’eau côtières (sur 39 au total) et les 16 masses d’eau de transition (sur 30 au total) retenues au titre du contrôle de surveillance. L’ensemble des résultats acquis, aussi bien sur les paramètres biologiques que chimiques, a permis de mettre à jour l’évaluation de l’état des masses d’eau affiché sur l’atlas DCE accessible sur la page web d’Envlit correspondante.
Tipo: Text
Palavras-chave: DCE; Bassin Loire-Bretagne; Contrôle de surveillance; Eaux côtières et eaux de transition; WFD; Loire Bretagne district; Monitoring; Coastal waters and transitional waters.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00254/36502/35049.pdf

The influence of natural dissolved organic matter on herbicide toxicity to marine microalgae is species-dependent
Provedor de dados: 5
Autores: Coquille, Nathalie; Menard, Dominique; Rouxel, Julien; Dupraz, Valentin; Eon, Melissa; Pardon, Patrick; Budzinski, Helene; Morin, Soizic; Parlanti, Edith; Stachowski-haberkorn, Sabine.
Microalgae, which are the foundation of aquatic food webs, may be the indirect target of herbicides used for agricultural and urban applications. Microalgae also interact with other compounds from their environment, such as natural dissolved organic matter (DOM), which can itself interact with herbicides. This study aimed to evaluate the influence of natural DOM on the toxicity of three herbicides (diuron, irgarol and S-metolachlor), singly and in ternary mixtures, to two marine microalgae, Chaetoceros calcitrans and Tetraselmis suecica, in monospecific, non-axenic cultures. Effects on growth, photosynthetic efficiency (Ф’M) and relative lipid content were evaluated. The chemical environment (herbicide and nutrient concentrations, dissolved organic carbon...
Tipo: Text
Palavras-chave: Microalgae; Herbicides; Natural dissolved organic matter; DOM; Toxicity; Interactions.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00428/53964/55113.pdf

Toxicity of binary mixtures of pesticides to the marine microalgae Tisochrysis lutea and Skeletonema marinoi: Substance interactions and physiological impacts
Provedor de dados: 5
Autores: Dupraz, Valentin; Ménard, Dominique; Akcha, Farida; Budzinski, Hélène; Stachowski-haberkorn, Sabine.
This study screened binary mixtures of pesticides for potential synergistic interaction effects on growth of the marine microalgae Tisochrysis lutea and Skeletonema marinoi. It also examined the single and combined effects of three of the most toxic substances on microalgal physiology. Single substances were first tested on each microalgal species to determine their respective EC50 and concentration-response relationships. The toxicity of six and seven binary mixtures was then evaluated in microplate experiments on the growth of T. lutea and S. marinoi, respectively, using two mixture modelling approaches: isobolograms and the MIXTOX tool, based on Concentration Addition (CA) or Independent Action (IA) models. Significant cases of antagonism (for both...
Tipo: Text
Palavras-chave: ROS; Photosynthesis; Lipids; Synergy; Isoproturon; Metazachlor.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00488/59928/63131.pdf

Projet COMPACT : COmmunautés micro-algales : effets de la Matière organique dissoute et des Pesticides sur l’Activité photosynthétique et la Composition Taxonomique
Provedor de dados: 5
Autores: Coquille, Nathalie; Maurer, Daniele; Auby, Isabelle; Budzinski, Helene; Stachowski-haberkorn, Sabine; Morin, Soizick; Parlanti, Edith; Vedrenne, J.; Jan, G.; Menard, Dominique; Dupraz, Valentin; Rigouin, Loic; Gouriou, Laure; D'Amico, Florence; Tournaire, Marie-pierre; Meteigner, Claire; Perriere-rumebe, Myriam; Mounguengui, A.; Tapie, Nathalie; Chevance-demars, L.; Pardon, P.; Geneste, E.
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00276/38740/37283.pdf