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DECOMBIO - Contribution de la combustion de la biomasse aux PM10 en vallée de l’Arve : mise en place et qualification d’un dispositif de suivi Texte intégral
2016
Chevrier, Florie | JEžEK, Irena | Brulfert, Guillaume | MOčnik, Grisa | Marchand, Nicolas | Jaffrezo, Jean-Luc | Besombes, Jean-Luc
L’agriculture entre pollution atmospherique et changement climatique Texte intégral
2016
Cellier, Pierre | Génermont, Sophie,
Les agroécosystèmes sont des sources et des puits de polluants atmosphériques et de gaz à effet de serre et, par là-même, ils interviennent dans les relations entre climat et pollution de l’air. Cette contribution, positive ou négative, résulte de processus complexes, à la fois directs et indirects, et prend des formes très diverses : augmentation ou diminution des émissions et dépôts, augmentation attendue de la fréquence des feux, modification de la protection phytosanitaire etc. Comme pour la plupart des processus biologiques, les incertitudes sont importantes et les verrous de connaissances restent nombreux, alors qu’une connaissance des différents facteurs d’influence, naturels et anthropiques est nécessaire pour limiter la contribution des agroécosystèmes à la fois au changement climatique et à la pollution de l’air, tout en préservant les performances économiques de l’activité agricole. Enfin, l’agriculture est concernée par tout un ensemble de politiques publiques relatives au changement climatique et à la pollution de l’air, mais également à la pollution des eaux et à la protection de l’environnement, politiques publiques qui peuvent interagir en synergie ou être antagonistes. | Interactions between climate change and air pollution in the context of agriculture. Agroecosystems are sources and sinks of atmospheric pollutants and greenhouse gases. They are therefore involved in climate change and air pollution and their cross-relations. This contribution can be positive or negative. It results from complex processes, both direct and indirect, which is related to a range of topics: increase or decrease of emission and deposition, increase in fire frequency, change in plant protection etc. As for most of biological processes, there are large uncertainties and knowledge is lacking over a range of fields. However it is necessary to have a global overview of the involved processes and drivers when trying to limit the contribution of agroecosystem both to climate change and air pollution, with attention to the economic sustainability of agriculture under global change. Moreover agriculture activities refer to public policies related not only to climate change and air pollution but also water pollution or protection of the environment. These policies may interact positively or be antagonist.
Afficher plus [+] Moins [-]Synthèse des connaissances sur le transfert des pesticides vers l’atmosphère par volatilisation depuis les plantes Texte intégral
2015
Lichiheb, Nebila | Bedos, Carole | Personne, Erwan | Barriuso, Enrique
Les niveaux de concentration des pesticides dans l’atmosphère méritent une attention particulière de la part de la recherche compte tenu de leurs impacts potentiels sur la population et les écosystèmes. L’activité agricole constitue la principale source de contamination de l’atmosphère par les pesticides. Bien que la volatilisation depuis la plante soit reconnue plus intense et plus rapide que la volatilisation depuis le sol, cette voie de transfert est à ce jour la moins bien renseignée avec peu de modèles disponibles pour sa description. Le manque de connaissances est lié essentiellement à la complexité des interactions entre les processus ayant lieu à la surface de la feuille et qui sont en compétition avec la volatilisation, notamment la pénétration foliaire et la photodégradation. Cet article présente une synthèse bibliographique sur l’état des lieux des connaissances sur le processus de volatilisation des pesticides depuis un couvert végétal, de la pénétration foliaire et de la photodégradation, ainsi que les facteurs de contrôle de ces processus. Les méthodes de mesure ainsi que les modèles existants décrivant ces processus sont également présentés et analysés | The agricultural activity presents the main source of the atmospheric contamination by pesticides. The occurrence of pesticides in the atmosphere concerns the research community due to their potential impacts on population and ecosystems. The volatilization from plants is higher and faster than the volatilization from soil. However, this transfer pathway is difficult to assess with few available models. The lack of knowledge on pesticide volatilization from plants is essentially linked to the complex interactions between processes occurring at the leaf surface and competing with volatilization, such as leaf penetration and photodegradation. This article presents a bibliographic synthesis of the state of knowledge on pesticide volatilization from plants, leaf penetration, photodegradation and control factors of these processes. Measuring methods and existing models describing these processes are also presented and analyzed
Afficher plus [+] Moins [-]Comparison of translocation methods to conserve metallophyte communities in the Southeastern D.R. Congo Texte intégral
2015
Le Stradic, Soizig | Seleck, Maxime | Lebrun, Jean | Boisson, Sylvain | Handjila, G. | Faucon, Michel-Pierre | Enk, T. | Mahy, Grégory
peer reviewed | In southeastern Democratic Republic of Congo, unique metallophyte communities supporting numerous endemic species occurred on the highly mineralized copper cobalt (Cu–Co) hills throughout the province. These hills are economically valuable mineral reserves; mining activities represent therefore a threat to the long-term persistence of these communities. Ex situ conservation program was set up by a mining company to rescue and conserve the diversity of Cu–Co communities until restoration activities are initiated. Two kinds of Cu–Co communities: the steppe and the steppic savanna, were translocated using topsoil spreading and whole-turf translocation. In this study, we assessed the effectiveness of these two techniques in conserving Cu–Co communities and their potential use in future restoration programs. More than 2 years after the translocation, whole-turf translocation appeared to be the better technique for ex situ conservation of endemic Cu–Co species. Not only did whole-turf successfully translocate numerous target species that were not present in the topsoil areas, but it also resulted in fewer ruderal and non-target species compared to topsoil spreading. Topsoil spreading recorded low seedling emergence from seed bank due to large proportions of dormant seeds or the absence of a seed bank, especially for the steppic savanna. Restoration of the steppe is currently more successful than for steppic savanna where the lack of dominant and structuring species likely contributed to divergence in species composition compared to reference ecosystem. Our study stresses the fact that tropical old-growth grasslands, which require probably several centuries to assemble, are difficult to restore or translocate. © 2015 Springer-Verlag Berlin Heidelberg
Afficher plus [+] Moins [-]The Air Quality in African Rural Environments. Preliminary Implications for Health: The Case of Respiratory Disease in the Northern Benin Texte intégral
2014
De Longueville, Florence | Hountondji, Yvon-Carmen | Ozer, Pierre | Henry, Sabine
The Air Quality in African Rural Environments. Preliminary Implications for Health: The Case of Respiratory Disease in the Northern Benin Texte intégral
2014
De Longueville, Florence | Hountondji, Yvon-Carmen | Ozer, Pierre | Henry, Sabine
peer reviewed | Recently, the World Health Organization’s International Association for Research on Cancer classified outdoor air pollution as carcinogenic to humans and puts air pollution in the same category as tobacco smoke, UV radiation, and plutonium. The ambient air is polluted by emissions from motor vehicles, industrial processes, power generation, household combustion of solid fuel, and other sources. Dust storms lead to particulate levels that exceed internationally recommended levels, especially near the Sahara. However, this source of air pollution appears to be under-studied, particularly in the literature devoted to human health impacts in West Africa. More than 50 % of the total dust emitted into the atmosphere comes from the Sahara. These aerosols contribute to increase the concentrations of particles smaller than 10 μm (PM10), which are breathable particles. This study is the first designed to assess the real impact of Saharan dust on air quality and respiratory health of children in a region of West Africa. Dust events having affected the Northern Benin during the dry seasons between 2003 and 2007 were determined. The analyzed health data are the monthly rates of acute lower respiratory infections (ALRI). Over the entire study period, 61 days of dust events were observed in the region. They recorded on average a daily PM10 concentration of 1017 μg m−3, more than 18 times higher than that calculated on all days without dust events. The study also highlighted a mean increase of 12.5 % of ALRI rates during the months recording dust events. The use of daily health data should help to refine these initial results in the future.
Afficher plus [+] Moins [-]The Air Quality in African Rural Environments. Preliminary Implications for Health: The Case of Respiratory Disease in the Northern Benin Texte intégral
2014
De Longueville, Florence | Hountondji, Yvon | Ozer, Pierre | Henry, Sabine
Recently, the World Health Organization’s International Association for Research on Cancer classified outdoor air pollution as carcinogenic to humans and puts air pollution in the same category as tobacco smoke, UV radiation, and plutonium. The ambient air is polluted by emissions from motor vehicles, industrial processes, power generation, household combustion of solid fuel, and other sources. Dust storms lead to particulate levels that exceed internationally recommended levels, especially near the Sahara. However, this source of air pollution appears to be under-studied, particularly in the literature devoted to human health impacts in West Africa. More than 50 % of the total dust emitted into the atmosphere comes from the Sahara. These aerosols contribute to increase the concentrations of particles smaller than 10 μm (PM₁₀), which are breathable particles. This study is the first designed to assess the real impact of Saharan dust on air quality and respiratory health of children in a region of West Africa. Dust events having affected the Northern Benin during the dry seasons between 2003 and 2007 were determined. The analyzed health data are the monthly rates of acute lower respiratory infections (ALRI). Over the entire study period, 61 days of dust events were observed in the region. They recorded on average a daily PM₁₀concentration of 1017 μg m⁻³, more than 18 times higher than that calculated on all days without dust events. The study also highlighted a mean increase of 12.5 % of ALRI rates during the months recording dust events. The use of daily health data should help to refine these initial results in the future.
Afficher plus [+] Moins [-]Conséquences des pollutions atmosphériques sur l'agriculture et la forêt Texte intégral
2014
Castell, Jean-François
Conséquences des pollutions atmosphériques sur l'agriculture et la forêt. Séminaire Agriculture et pollution de l’air
Afficher plus [+] Moins [-]Microsporidia parasites disrupt the responses to cadmium exposure in a gammarid Texte intégral
2012
Gismondi, Eric | Rigaud, Thierry | Beisel, Jean-Nicolas | Cossu-Leguille, Carole
Microsporidia parasites disrupt the responses to cadmium exposure in a gammarid Texte intégral
2012
Gismondi, Eric | Rigaud, Thierry | Beisel, Jean-Nicolas | Cossu-Leguille, Carole
peer reviewed
Afficher plus [+] Moins [-]Microsporidia parasites disrupt the responses to cadmium exposure in a gammarid Texte intégral
2012
Gismondi, Eric | Rigaud, Thierry | Beisel, Jean-Nicolas | Cossu-Leguille, Carole
Microsporidia parasites are commonly found in amphipods, where they are often asymptomatic, vertically-transmitted and have several effects on host sexuality and behaviour. As amphipods are often used as models in ecotoxicological studies, we investigated the effect of microsporidian infections on energy reserves and defence capacities of Gammarus roeseli under cadmium stress. Only females were infected by two microsporidia parasites: Dictyocoela roeselum or Dictyocoela muelleri. In physiological conditions, microsporidia had no major effect on energy reserves and defence capacities of G. roeseli, while under cadmium exposure, energy reserves and antioxidant defence were weaker in infected females. Moreover, higher malondialdehyde levels detected in infected females revealed that they suffered more cellular damages. Our results suggest that microsporidia may affect gammarid fitness in stressful conditions, when parasitic stress cannot be compensated by the host. Consequently, microsporidia parasites should be a factor necessary to take into account in ecotoxicology studies involving amphipods.
Afficher plus [+] Moins [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation Texte intégral
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège | Dynecar - Université Antilles Guyane
Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation Texte intégral
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège | Dynecar - Université Antilles Guyane
peer reviewed | Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of b-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to b-HCH.
Afficher plus [+] Moins [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation Texte intégral
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles
Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of β-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to β-HCH.
Afficher plus [+] Moins [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation Texte intégral
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles
Direction Régionale de l’Environnement de la Guadeloupe | Centre Interfacultaire de Recherches en Océanologie - MARE | Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon weremeasured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examinethe bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a generaland heavy contamination of the entire food web. They revealed the strong accumulation of pollutants byjuveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in thebioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone andmonohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of b-HCH wasonly influenced by animal lipid content. The biomagnification potential of chlordecone through the foodchain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulationprocess. In contrast, bioconcentration by passive diffusion from water seemed to be themain exposure route of biota to b-HCH. | Linked papers: Coat et al. 2009 and Lefrançois et al. 2010
Afficher plus [+] Moins [-]Inter-species differences for polychlorinated biphenyls and polybrominated diphenyl ethers in marine top predators from the Southern North Sea: Part 1. Accumulation patterns in harbour seals and harbour porpoises Texte intégral
2009
Weijs, Liesbeth | Dirtu, Alin C | Das, Krishna | Gheorghe, Adriana | Reijnders, Peter | Neels, Hugo | Blust, Ronny | Covaci, Adrian | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Harbour porpoises (Phocoena phocoena) and harbour seals (Phoca vitulina) are two representative top predator species of the North Sea ecosystem. The median values of sum of 21 polychlorinated biphenyl (PCB) congeners and sum of 10 polybrominated diphenyl ether (PBDE) congeners were 23.1 mg/g lipid weight (lw) and 0.33 mg/g lw in blubber of harbour seals (n ¼ 28) and 12.4 mg/g lw and 0.76 mg/g lw in blubber of harbour porpoises (n¼ 35), respectively. For both species, the highest PCB concentrations were observed in adult males indicating bioaccumulation. On the contrary, the highest PBDE concentrations were measured in juveniles, likely due to better-developed metabolic capacities with age in adults. A higher contribution of lower chlorinated and non-persistent congeners, such as CB 52, CB 95, CB 101, and CB 149, together with higher contributions of other PBDE congeners than BDE 47, indicated that harbour porpoises are unable to metabolize these compounds. Harbour seals showed a higher ability to metabolize PCBs and PBDEs.
Afficher plus [+] Moins [-]Utilisation d'un bio-indicateur vegetal pour la mesure de l'ozone en montagne Texte intégral
1988
Garrec, J.P. | Rosé, Christophe
