Suchergebnisse

The increasing contamination by micropollutants in freshwater systems has become a major problem in modern societies, giving rise to toxicological, sanitary and economical concerns. In 2010 the French government adopted a plan for a 50% reduction over 10 years in the use of pesticides which promotes research on contamination monitoring. Diatom bio-indication tools in rivers have been standardized and normalized (AFNOR NFT 90 354 ; CEN – EN 13946 & EN 14407) and are adapted to assess nutrient and organic matter levels. However these indicators do not assess micropollutants contamination despite diatoms being known to be sensitive to pesticide pollution. The objective of this study is to assess whether bio-indicators based on diatom communities could be developed to assess the impact of pesticide contamination, especially herbicides, on freshwater ecosystems quality. The hypothesis that increasing herbicide concentration reduces diatom diversity wastested on a diatom data set from the French Water Framework Directive monitoring network. The data set includes more than 2000 samples from 14 ecoregions from eastern France over the period 2000 - 2008. To each sample corresponds a list of diatom taxa and 531micropollutants (herbicides, insecticides, fungicides, heavy metals and organic micropollutants) concentration measurements. Diatom diversity was calculated by means of2 classic indices: Shannon's H' (Shannon, 1948) and Simpson's D (Simpson, 1949) and 3taxonomic distinctness indices: ?, ?* and ?+ (Clarke and Warwick, 1998). This poster describes preliminary results which may lead to new bio-indication metrics adapted to pesticide contamination.

International audience ; The increasing contamination by micropollutants in freshwater systems has become a major problem in modern societies, giving rise to toxicological, sanitary and economical concerns. In 2010 the French government adopted a plan for a 50% reduction over 10 years in the use of pesticides which promotes research on contamination monitoring. Diatom bio-indication tools in rivers have been standardized and normalized (AFNOR NFT 90 354 ; CEN – EN 13946 & EN 14407) and are adapted to assess nutrient and organic matter levels. However these indicators do not assess micropollutants contamination despite diatoms being known to be sensitive to pesticide pollution. The objective of this study is to assess whether bio-indicators based on diatom communities could be developed to assess the impact of pesticide contamination, especially herbicides, on freshwater ecosystems quality. The hypothesis that increasing herbicide concentration reduces diatom diversity wastested on a diatom data set from the French Water Framework Directive monitoring network. The data set includes more than 2000 samples from 14 ecoregions from eastern France over the period 2000 - 2008. To each sample corresponds a list of diatom taxa and 531micropollutants (herbicides, insecticides, fungicides, heavy metals and organic micropollutants) concentration measurements. Diatom diversity was calculated by means of2 classic indices: Shannon's H' (Shannon, 1948) and Simpson's D (Simpson, 1949) and 3taxonomic distinctness indices: ?, ?* and ?+ (Clarke and Warwick, 1998). This poster describes preliminary results which may lead to new bio-indication metrics adapted to pesticide contamination.

International audience ; The increasing contamination by micropollutants in freshwater systems has become a major problem in modern societies, giving rise to toxicological, sanitary and economical concerns. In 2010 the French government adopted a plan for a 50% reduction over 10 years in the use of pesticides which promotes research on contamination monitoring. Diatom bio-indication tools in rivers have been standardized and normalized (AFNOR NFT 90 354 ; CEN – EN 13946 & EN 14407) and are adapted to assess nutrient and organic matter levels. However these indicators do not assess micropollutants contamination despite diatoms being known to be sensitive to pesticide pollution. The objective of this study is to assess whether bio-indicators based on diatom communities could be developed to assess the impact of pesticide contamination, especially herbicides, on freshwater ecosystems quality. The hypothesis that increasing herbicide concentration reduces diatom diversity wastested on a diatom data set from the French Water Framework Directive monitoring network. The data set includes more than 2000 samples from 14 ecoregions from eastern France over the period 2000 - 2008. To each sample corresponds a list of diatom taxa and 531micropollutants (herbicides, insecticides, fungicides, heavy metals and organic micropollutants) concentration measurements. Diatom diversity was calculated by means of2 classic indices: Shannon's H' (Shannon, 1948) and Simpson's D (Simpson, 1949) and 3taxonomic distinctness indices: ?, ?* and ?+ (Clarke and Warwick, 1998). This poster describes preliminary results which may lead to new bio-indication metrics adapted to pesticide contamination.

International audience ; The increasing contamination by micropollutants in freshwater systems has become a major problem in modern societies, giving rise to toxicological, sanitary and economical concerns. In 2010 the French government adopted a plan for a 50% reduction over 10 years in the use of pesticides which promotes research on contamination monitoring. Diatom bio-indication tools in rivers have been standardized and normalized (AFNOR NFT 90 354 ; CEN – EN 13946 & EN 14407) and are adapted to assess nutrient and organic matter levels. However these indicators do not assess micropollutants contamination despite diatoms being known to be sensitive to pesticide pollution. The objective of this study is to assess whether bio-indicators based on diatom communities could be developed to assess the impact of pesticide contamination, especially herbicides, on freshwater ecosystems quality. The hypothesis that increasing herbicide concentration reduces diatom diversity wastested on a diatom data set from the French Water Framework Directive monitoring network. The data set includes more than 2000 samples from 14 ecoregions from eastern France over the period 2000 - 2008. To each sample corresponds a list of diatom taxa and 531micropollutants (herbicides, insecticides, fungicides, heavy metals and organic micropollutants) concentration measurements. Diatom diversity was calculated by means of2 classic indices: Shannon's H' (Shannon, 1948) and Simpson's D (Simpson, 1949) and 3taxonomic distinctness indices: ?, ?* and ?+ (Clarke and Warwick, 1998). This poster describes preliminary results which may lead to new bio-indication metrics adapted to pesticide contamination.

Nesse artigo apresento uma análise do caso de parricídio/ fraticídio cometido por um jovem camponês francês, nascido na comuna de Courvaudon, Pierre Rivière que em 3 de junho de 1835, aos vinte anos, assassinou a golpes de foice sua mãe grávida de sete meses, sua irmã de 18 anos, e seu irmão de sete anos. O livro intitulado Eu, Pierre Rivière, que degolei minha mãe, minha irmã e meu irmão produzido pelo trabalho de uma equipe de pesquisadores, no Collège de France, sob a coordenação de Michel Foucault em 1973, apresenta em seu conjunto notícias de jornais, testemunhos, interrogatórios, laudos médicos e uma gama de diferentes discursos. Para empreender a análise do nó entre a escrita e o assassinato, utilizo a relação entre a escrita e o autor demarcando o personagem Rivière no desdobramento, na ordem do corpo e da linguagem.

For some ten years more and more cities are trying to rebuild a link between water and urban areas, because they worry about environmental matters and they wanted to meet the "nature" need of inhabitants. This launched banks recapturing projects are supervised by management tools, which exist at different scales, but always for the sake of preserving the biodiversity, of protecting water resources and offer to men a calmed connection with water. In the case of the planning of the river Colmont in Gorron objectives are to facilitate uses of the river, which are slown by dense vegetation or rare accesses, and to favour a good water flow. With the help of the diagnosis in Gorron we can consider several planning solutions for the river Colmont, in wildest or more urban spaces. A well-reasoned rivers management , which follows government management tools, can protect landscapes and biodiversity while offering well-reasoned maintenance solutions for urban areas. ; Depuis quelques dizaines d'années, de plus en plus de villes cherchent à reconstruire un lien à l'eau en milieu urbain, par souci des problèmes environnementaux ou pour répondre à un besoin de retour à la "nature" de la part des habitants. Les projets de reconquête des berges alors lancés sont encadrés par des outils de gestion qui se déclinent à différentes échelles, mais toujours dans un souci de préserver la biodiversité, de protéger la ressource en eau et d'offrir aux hommes une relation apaisée à l'eau. Dans le cas du réaménagement de la rivière Colmont à Gorron (53), les objectifs sont à la fois de faciliter les usages autour de l'eau, qui sont freinés par une végétation dense ou des accès rares, et de favoriser un bon écoulement de l'eau. Le diagnostic effectué sur Gorron permet d'envisager toutes sortes de solutions pour réaménager la rivière Colmont, que ce soit dans sa partie plus sauvage ou urbaine. Une gestion raisonnée des rivières et cours d'eau suivant les outils de gestion mis en place le gouvernement permet de protéger les paysages et la biodiversité des rivières, tout en offrant des solutions d'entretien raisonnées pour les zones urbaines.

Depuis les années 1970, des mobilisations citoyennes et des interventions gouvernementales donnent lieu à une série de projets de décontamination et de réhabilitation des rivières urbaines. Prenant place dans un contexte de montée des préoccupations environnementales, ces projets semblent signaler une reconquête des fronts d'eau par une population urbaine qui en aurait été privée par le passé. Dans cet article, nous examinons les relations que les populations urbaines entretiennent envers leurs environnements fluviaux dans le temps long pour deux tributaires situés de part et d'autre du fleuve Saint-Laurent et qui traversent deux villes de taille moyenne du Québec : Shawinigan, pour la rivière Saint-Maurice, sur la rive nord, et Drummondville, pour la rivière Saint-François, sur la rive sud. Par cette démarche, nous souhaitons montrer la façon dont les types de relations que les populations entretiennent avec les rivières, plutôt que de se succéder dans le temps, se juxtaposent. De même, nous souhaitons dégager les facteurs qui modulent l'intensité des mobilisations entourant le processus continuel d'appropriation des berges et des cours d'eau.

La rivière est un écosystème complexe souvent mal connu, véritable écrin de biodiversité pour peu qu'on sache en prendre soin et s'y intéresser. La rivière, c'est la face émergée du grand cycle de l'eau et de son bon fonctionnement. Elle est souvent le témoin d'un usage raisonné ou non de cette ressource, depuis les ruisseaux qui lui donnent vie. Au sein de la riche biodiversité des rivières, certaines espèces emblématiques sont considérées comme espèces « parapluie » car elles sont bio-indicatrices de la qualité des milieux. On les appelle ainsi car en les protégeant à travers la restauration de leurs habitats, c'est tout un cortège d'autres espèces qui en bénéficie. Nous partirons à la rencontre de certaines d'entre elles. Depuis 40 ans, l'état physico-chimique des rivières s'est progressivement amélioré, surtout grâce au développement des systèmes d'assainissement. Aujourd'hui, de nouvelles pressions s'accentuent, et jouent sur la diminution de la disponibilité et de la qualité de l'eau, face à nos besoins toujours grandissants.