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Characterization of river pollution at the watershed scale Full text
2016
Lesueur Jannoyer M. | Mottes C. | Clostre F. | Carles C. | Guene M. | Plet J. | Della Rossa P. | Bazizi A. | Cattan P.
The challenge of knowledge representation to better understand environmental pollution Full text
2016
Cattan P. | Tonneau J.P. | Charlier J.B. | Ducreux L. | Voltz M. | Bricquet J.P. | Andrieux P. | Arnaud L. | Lesueur Jannoyer M.
Crisis management of chronic pollution: contaminated soil and human health Full text
2016
Lesueur Jannoyer M. (ed.) | Cattan P. (ed.) | Woignier T. (ed.) | Clostre F. (ed.)
Crisis Management of Chronic Pollution: Contaminated Soil and Human Health deals with a long term pollution problem, generated by the former use of organochlorine pesticides. Through a case study of the chlordecone pollution in the French West Indies, the authors illustrate a global and systemic mobilization of research institutions and public services. This "management model", together with its major results, the approach and lessons to be learned, could be useful to other situations. This book gathers all the works that have been carried out over the last ten years or more and links them to decision makers' actions and stakeholders' expectations. This reference fills a gap in the literature on chronic pollution. (Résumé d'auteur)
Show more [+] Less [-]SWAT: Agricultural water and nonpoint source pollution management at a watershed scale Full text
2016
Volk, Martin | Bosch, David | Nangia, Vinay | Narasimhan, Balaji
Global change and demographic changes increasingly cause water, food, and health problems at many places of the world. In addition, the growth in bioenergy production leads to land-use change and associated environmental impacts. This Special Issue addresses many of the challenges of agri-cultural, water and nonpoint source pollution management at the watershed scale. In this regard, the Soil and Water Assessment Tool (SWAT) model (Arnold et al., 1998; Arnold and Fohrer, 2005) has proven to be an effective mechanism for assessing water resource and nonpoint source pollution problems for a wide range of scales and environmental conditions across the globe (Gassman et al., 2007). The model is a continuation of nearly 30 years of research efforts by the USDA Agricultural Research Service (ARS). SWAT continues to evolve as users determine needed improvements that will enable more accurate simulation of currently supported processes and new functionalities that will expand the SWAT simulation domain, reflecting the above mentioned challenges.
Show more [+] Less [-]Analysis of cloudiness and solar radiation diurnal cycles for a better understanding of the forests greenness mean annual cycle in Central Africa. | Apport de l'analyse des cycles diurnes de nébulosité et de radiation solaire pour comprendre le cycle saisonnier moyen d'activité photosynthétique de la forêt en Afrique Centrale. Full text
2016
Philippon, Nathalie | de Lapparent, B. | Gond, V. | Bigot, S. | Brou, Yao Télesphore | Camberlin, Pierre | Cornu, G. | Dubreuil, Vincent | Martiny, Nadège | Morel, Béatrice | Moron, M. | Seze, G. | Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) ; Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG) ; Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]) | Biens et services des écosystèmes forestiers tropicaux : l'enjeu du changement global (UPR BSEF) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | UMR 228 Espace-Dev, Espace pour le développement ; Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM)-Université de Guyane (UG)-Université des Antilles (UA) | Biogéosciences [UMR 6282] (BGS) ; Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Littoral, Environnement, Télédétection, Géomatique (LETG - Rennes) ; Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG) ; Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN) ; Université de Nantes (UN)-Université de Nantes (UN)-Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN) ; Université de Nantes (UN)-Université de Nantes (UN) | Energy Lab (ENERGY Lab) ; Université de La Réunion (UR) | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Météorologie Dynamique (UMR 8539) (LMD) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X) ; Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-École nationale des ponts et chaussées (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS-PSL ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL) | CNES (projet VEGREENE 2014-2015) | J.-M. Fallot, D. Joly & N. Bernard
6 pages | International audience | To better understand the Central Africa forests sensitivity toclimate variability, we jointly analyse the mean annual cycles of greenness, rainfall, cloudiness and solarradiation for the target region 0-5°N/12-19°E using high resolution satellite data. Our results demonstrate theimportance of the diurnal scale for understanding the mean annual cycles of rainfall, cloudiness and solarradiation and the way they shape those of forest greenness. They also suggest that whereas the March-Mayrainy season appears optimal for greenness especially because of favorable light conditions, water availabilityis the main controlling factor in December-January the main dry season and in February at the start of the firstvegetative season. Regarding the little dry season and the second rainy season (July-October) light availabilitymight be the main limiting factor to forests photosynthetic activity. | Afin de mieux comprendre la sensibilité de la forêt d'Afrique Centrale à la variabilité climatiqueactuelle, une analyse détaillée des cycles saisonniers moyens d'activité photosynthétique, de précipitations, decouverture nuageuse et de radiation solaire est menée pour la région 0-5°N/12-19°E, en s'appuyant sur desobservations satellites haute résolution spatiale et temporelle. Nos résultats montrent tout d'abord que l'échellediurne est une échelle clé pour comprendre les cycles saisonniers moyens de précipitations, nébulosité etradiation solaire, et comment ils façonnent celui d'activité photosynthétique des forêts. Ensuite, alors que lasaison mars-mai semble optimale pour l'activité photosynthétique des forêts en raison d'une bonne disponibilitéen lumière, la disponibilité en eau est le facteur de contrôle principal durant la grande saison sèche (décembrejanvier)et au démarrage de la 1ère saison végétative (février). De juillet à octobre, la plus faible disponibilitéen lumière pourrait être le principal facteur explicatif à la baisse de l'activité photosynthétique.
Show more [+] Less [-]Dual mechanochemical immobilization of heavy metals and decomposition of halogenated compounds in automobile shredder residue using a nano-sized metallic calcium reagent Full text
2016
Mallampati, Srinivasa Reddy | Lee, Byoung Ho | Mitoma, Yoshiharu | Simion, Cristian
Simultaneous immobilization of heavy metals and decomposition of halogenated organic compounds in different fractions of automobile shredder residue (ASR) were achieved with a nano-sized metallic calcium through a 60-min ball milling treatment. Heavy metal (HM) immobilization and chlorinated/brominated compound (CBC) decomposition efficiencies both reached 90–100 %, after ball milling with nanometallic calcium/calcium oxide (Ca/CaO) dispersion, regardless of ASR particle size (1.0, 0.45–1.0, and 0.250 mm). Concentrations of leachable HMs substantially decreased to a level lower than the regulatory standard limits (Co and Cd 0.3 mg L⁻¹; Cr 1.5 mg L⁻¹; Fe, Pb, and Zn 3.0 mg L⁻¹; Mn and Ni 1 mg L⁻¹) proposed by the Korean hazardous waste elution standard regulatory threshold. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) element maps/spectra showed that while the amounts of HMs and CBCs detectable in ASR significantly decreased, the calcium mass percentage increased. X-ray powder diffraction (XRD) patterns indicate that the main fraction of enclosed/bound materials on ASR includes Ca-associated crystalline complexes that remarkably inhibit HM desorption and simultaneously transform dangerous CBCs into harmless compounds. The use of a nanometallic Ca/CaO mixture in a mechanochemical process to treat hazardous ASR (dry conditions) is an innovative approach to remediate cross-contaminated residues with heavy metals and halogenated compounds.
Show more [+] Less [-]Dielectric barrier discharge plasma induced degradation of aqueous atrazine Full text
2016
Feng, Jingwei | Jiang, Lin | Zhu, Dan | Su, Kuizu | Zhao, Dayong | Zhang, Jibiao | Zheng, Zheng
Degradation of herbicide atrazine in aqueous solution was investigated using a plate type dielectric barrier discharge (DBD) plasma reactor. DBD plasma was generated at the gas-liquid interface of the formed water film. At discharge time of 14 min, atrazine was degradated effectively with a degradation rate of 99 % at the discharge power of 200 W. The experimental data fitted well with first-order kinetics and the energy efficiency for 90 % degradation of atrazine (G value) was calculated, obtaining a rate constant of 0.35 min⁻¹ and a G value of 1.27 × 10⁻¹⁰ mol J⁻¹ (98.76 mg kW⁻¹ h⁻¹) at a discharge power of 200 W, respectively. The addition of Fe²⁺ increased the rate constant and G value dramatically, and a significant decrease of the rate constant and G value was observed with the addition of radical scavengers (tert-butyl alcohol, isopropyl alcohol, or Na₂CO₃). The generated aqueous O₃ and H₂O₂ were determined, which promoted the degradation of herbicide atrazine. Dechlorination was observed and the experimentally detected Cl⁻ was 1.52 mg L⁻¹ at a discharge time of 14 min. The degradation intermediates of atrazine were detected by means of liquid chromatography-mass spectrometry; dechlorination, hydroxylation, dealkylation, and alkyl oxidation processes were involved in the degradation pathways of atrazine.
Show more [+] Less [-]Changes in speciation and leaching behaviors of heavy metals in dredged sediment solidified/stabilized with various materials Full text
2016
Bao, Jianping | Wang, Liang | Xiao, Man
Solidification/stabilization (S/S) of sediments is frequently used to treat contaminants in dredged sediments. In this study, sediment collected from the Pearl River Delta (China) was solidified/stabilized with three different kinds of functional materials: cement, lime and bentonite. Lime primarily acted via induced increases in pH, while cements stabilization occurred through their silicate-based systems and the main function of bentonite was adsorption. The speciation and leaching behaviors of specific heavy metals before and after S/S were analyzed and the results showed that the residual speciation of Cd, Cr, Ni, Pb and Zn increased in all treatments except for Cu, as the exchangeable speciation, carbonate-bound speciation and Fe-Mn-oxide-bound speciation of Cu (all of which could be stabilized) were less than 2 % of the total amount. Pb leaching only decreased when pH increased, while the mobility of Cr and Ni only decreased in response to the silicate-based systems. The leached portion of the Fe-Mn-oxide-bound speciation followed the order Zn > Cu > Ni/Cd > Pb > Cr. The leached portion of organic-matter-bound species was less than 4 % for Cd, Cr, Ni and Pb, but 35.1 % and 20.6 % for Cu and Zn, respectively.
Show more [+] Less [-]Emergency control system based on the analytical hierarchy process and coordinated development degree model for sudden water pollution accidents in the Middle Route of the South-to-North Water Transfer Project in China Full text
2016
Long, Yan | Xu, Guobin | Ma, Chao | Ma, Yukun
Water transfer projects are important for realizing reasonable allocation of water resources, but once a water pollution accident occurs during such a project, the water environment is exposed to enormous risks. Therefore, it is critical to determine an appropriate emergency control system (ECS) for sudden water pollution accidents that occur in water transfer projects. In this study, the analytical hierarchy process (AHP) integrated with the coordinated development degree model (CDDM) was used to develop the ECS. This ECS was developed into two parts, including the emergency risk assessment and the emergency control. Feasible emergency control targets and control technology were also proposed for different sudden water pollution accidents. A demonstrative project was conducted in the Fangshui to Puyang channel, which is part of the Beijing–Shijiazhuang Emergency Water Supply Project (BSP) in the Middle Route of the South-to-North Water Transfer Project (MR-SNWTP) in China. However, we could not use an actual toxic soluble pollutant to validate our ECS, so we performed the experiment with sucrose to test the ECS based on its concentration variation. The relative error of peak sucrose concentration was less than 20 %.
Show more [+] Less [-]Gamma radiolytic decomposition of endosulfan in aerated solution: the role of carbonate radical Full text
2016
Shah, Noor S. | Khan, Javed Ali | Al-Muhtaseb, Ala’a H. | Sayed, Murtaza | Khan, Hasan M.
The present study elaborates the removal of endosulfan, an emerging water pollutant and potential carcinogenic, in aerated solution. The influence of Cl⁻, NO₃ ⁻, NO₂ ⁻, CO₃ ²⁻, HCO₃ ⁻, SO₃ ²⁻, and humic acid was assessed on the radiolytic degradation of endosulfan. A strong inhibition on the radiolytic degradation of endosulfan was observed in the presence of NO₃ ⁻, NO₂ ⁻, and SO₃ ²⁻. Instead, a slight increase in the removal efficiency of endosulfan was observed at high concentrations of CO₃ ²⁻ and HCO₃ ⁻. The formation of CO₃ •⁻ in radiolytic degradation of endosulfan in the presence of CO₃ ²⁻ and HCO₃ ⁻ was demonstrated by adding SO₃ ²⁻ that rapidly react with CO₃ •⁻. The results indicate that CO₃ •⁻ formed from the reactions of CO₃ ²⁻ and HCO₃ ⁻ and commonly found in natural water can play an important role in the degradation of endosulfan and other sulfur containing electron-rich compounds. The study showed faster degradation of endosulfan at lower concentration compared to high concentration and removal was found to follow pseudo-first-order kinetic. Endosulfan ether was found as the main degradation product and degradation pathway was found to be initiated at the S=O bond of endosulfan. The efficiency of gamma irradiation in the removal of endosulfan was examined in terms of formation of short chain organic acids and chloride ion accumulation.
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