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Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff Texto completo
2012
Al-Wadaey, Ahmed | Wortmann, S. Charles | Franti, G. Thomas | Shapiro, A. Charles | Eisenhauer, E.Dean
Surface water contamination can often be reduced by passing runoff water through perennial grass filters. Research was conducted in 2006 to 2008 to evaluate the size of cool season grass filters consisting primarily of tall fescue (Festuca arundinacea Schreb) with some orchard grass (Dactylis glomerata L.) relative to drainage area size in reducing runoff sediment and phosphorus (P). The soil was Pohocco silt loam Typic Eutrochrepts with a median slope of 5.5 %. The grass filters occupying 1.1 and 4.3 % of the plot area were compared with no filter with four replications. The filters were planted in the V-shaped plot outlets which were 3.7x11.0 m in size. The filter effect on sediment and P concentration was determined from four natural runoff events when nearly all plots had runoff. Filter effect on runoff volume and contaminant load was determined using total runoff and composites of samples collected from 12 runoff events. Sediment concentration was reduced by 25 % with filters compared with no filter (from 1.10 to 1.47 gL(-1)), but P concentration was not affected. The 1.1 and 4.3 % filters, respectively, compared with having no grass filter, reduced: runoff volume by 54 and 79 %; sediment load by 67 and 84 % (357 to 58 kgha(-1)); total P load by 68 and 76 % (0.58 to 0.14 kgha(-1)); particulate P (PP) load by 66 and 82 % (0.39 to 0.07 kgha(-1)); and dissolved reactive P (DRP) load by 73 and 66 % (0.2 to 0.07 kgha(-1)), respectfully. A snowmelt runoff event had 56 % greater DRP concentration compared with rainfall-induced runoff events. Grass filters reduced sediment and P load largely by reducing runoff volume rather than reducing concentration. Well-designed and well-placed grass filters that occupy 1.0 to 1.5 % of the drainage area and intercept a uniform flow of runoff from a drainage area can reduce sediment and nutrient loss in runoff by greater than 50 %.
Mostrar más [+] Menos [-]Organic waste-borne ZnS nanoparticles: The forgotten ones Texto completo
2022
Levard, Clément | Le Bars, Maureen | Fromentini, T. | Legros, Samuel | Doelsch, Emmanuel
Contrasted fate of zinc sulfide nanoparticles in soil revealed by a combination of X-ray absorption spectroscopy, diffusive gradient in thin films and isotope tracing Texto completo
2022
Le Bars, Maureen | Legros, Samuel | Levard, Clément | Chevassus-Rosset, Claire | Montes, Mélanie | Tella, Marie | Borschneck, Daniel | Guihou, Abel | Angeletti, Bernard | Doelsch, Emmanuel
Incidental zinc sulfide nanoparticles (nano-ZnS) are spread on soils through organic waste (OW) recycling. Here we performed soil incubations with synthetic nano-ZnS (3 nm crystallite size), representative of the form found in OW. We used an original set of techniques to reveal the fate of nano-ZnS in two soils with different properties. 68Zn tracing and nano-DGT were combined during soil incubation to discriminate the available natural Zn from the soil, and the available Zn from the dissolved nano-68ZnS. This combination was crucial to highlight the dissolution of nano-68ZnS as of the third day of incubation. Based on the extended X-ray absorption fine structure, we revealed faster dissolution of nano-ZnS in clayey soil (82% within 1 month) than in sandy soil (2% within 1 month). However, the nano-DGT results showed limited availability of Zn released by nano-ZnS dissolution after 1 month in the clayey soil compared with the sandy soil. These results highlighted: (i) the key role of soil properties for nano-ZnS fate, and (ii) fast dissolution of nano-ZnS in clayey soil. Finally, the higher availability of Zn in the sandy soil despite the lower nano-ZnS dissolution rate is counterintuitive. This study demonstrated that, in addition to nanoparticle dissolution, it is also essential to take the availability of released ions into account when studying the fate of nanoparticles in soil.
Mostrar más [+] Menos [-]Long-term pollution by chlordecone of tropical volcanic soils in the French West Indies: New insights and improvement of previous predictions Texto completo
2022
Comte, Irina | Pradel, Alice | Grabit, Armand | Mottes, Charles | Pak, Lai-Ting | Cattan, Philippe
Chlordecone (CLD), was widely applied in banana fields in the French West Indies from 1972 to 1993. The WISORCH model was constructed to assess soil contamination by CLD and estimated that it lasts from 100 to 600 years, depending on leaching intensity and assuming no degradation. However, recent studies demonstrated that CLD is degraded in the environment, hence questioning the reliability of previous estimations. This paper shows how to improve the model and provides insights into the long-term dissipation of CLD. In-situ observations were made in nearly 2545 plots between 2001 and 2020, and 17 plots were sampled at two dates. Results of soil analyses showed an unexpected 4-fold decrease in CLD concentrations in the soil, in contrast to simulations made using the first version of WISORCH at the time. Neither erosion, nor CLD leaching explained these discrepancies. In a top-down modeling approach, these new observations of CLD concentrations led us to implement a new dissipation process in the WISORCH model that corresponds to a DT50 dissipation half-life of 5 years. The new version of the improved model allowed us to update the prediction of the persistence of soil pollution, with soil decontamination estimated for the 2070s. This development calls for re-evaluation of soil pollution status. Further validation of the new version of WISORCH is needed so it can contribute to crop management on contaminated soil.
Mostrar más [+] Menos [-]Contaminants in Atlantic walruses Part 2: Relationships with endocrine and immune systems Texto completo
2018
Routti, Heli | Diot, Beatrice | Panti, Cristina | Duale, Nur | Fossi, Maria Cristina | Harju, Mikael | Kovacs, Kit M. | Lydersen, Christian | Scotter, Sophie | Villanger, Gro Dehli | Bourgeon, Sophie
acceptedVersion
Mostrar más [+] Menos [-]Node-to-node field calibration of wireless distributed air pollution sensor network Texto completo
2017
Kizel, Fadi | Etzion, Yael | Shafran-Nathan, Rakefet | Levy, Ilan | Fishbain, Barak | Bartonova, Alena | Broday, David M.
acceptedVersion
Mostrar más [+] Menos [-]Impact of urban planning on air quality since 1998 in Thionville area (Moselle, France)Passive samplers method and lichens sampling | Impact de l'aménagement urbain de l'agglomération thionvilloise (Moselle, France) sur la qualité de l'air depuis 1998Méthode des échantillonneurs passifs et relevés lichéniques Texto completo
2001
Laval-Gilly, Philippe | Falla, Jaïro | Morlot, Dominique
Pollution atmosphérique, climat et société : quelle place aujourd’hui dans la « ville durable » ? Une analyse comparée à partir de la littérature francophone et anglophone Texto completo
2017
Hamman, Philippe | Sociétés, acteurs, gouvernement en Europe (SAGE) ; École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Sociétés, Acteurs, Gouvernement en Europe (SAGE) ; Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
La problématique air-climat-société est caractérisée à l’heure actuelle par une double propriété de transversalité (les polluants altérant la qualité de l’air et responsables des gaz à effet de serre sont souvent les mêmes) et de multiscalarité (de l’échelle du bâti à celle de la planète). À partir de ce point de départ et sous l’angle des sciences sociales, l’article interroge la place dévolue à ces enjeux au sein du répertoire de la « ville durable », qui marque de plus en plus les façons de faire et vivre la ville. Nous déplaçons le regard à partir de ce qui est souvent lu d’abord comme des questions techniques (mesure de la pollution atmosphérique, etc.), pour les restituer dans leur épaisseur sociale, celle de l’action publique autant que des modes de vie en ville. Méthodologiquement, nous procédons par une approche bibliométrique comparée, à partir d’un corpus de 18 revues scientifiques, francophones et anglophones. Une analyse statistique et textuelle a été conduite avec le logiciel libre IRaMuTeQ, spécifiant des univers de co-occurrence lexicale. Elle établit la portée de trois déclinaisons structurantes dans les lectures à la fois notionnelles, critiques et plus appliquées de la durabilité urbaine : le changement climatique et ses modèles, les déplacements et transports urbains, et le métabolisme urbain rapporté aux consommations d’énergie et aux flux de matières. Au final, c’est une double dimension théorique et pratique qui fait sens, et qu’atteste la démonstration à travers la force des liens entre les termes récurrents, les classes lexicales et les segments significatifs dégagés.
Mostrar más [+] Menos [-]Factors affecting farmers’ use of organic and inorganic fertilizers in South Asia Texto completo
2021
Aryal, Jeetendra P | Sapkota, Tek Bahadur | Krupnik, Timothy J. | Rahut, Dil B | Jat, Mangi Lal | Stirling, Clare M
Factors affecting farmers’ use of organic and inorganic fertilizers in South Asia Texto completo
2021
Aryal, Jeetendra P | Sapkota, Tek Bahadur | Krupnik, Timothy J. | Rahut, Dil B | Jat, Mangi Lal | Stirling, Clare M
Fertilizer, though one of the most essential inputs for increasing agricultural production, is a leading cause of nitrous oxide emissions from agriculture, contributing significantly to global warming. Therefore, understanding factors affecting farmers’ use of fertilizers is crucial to develop strategies to improve its efficient use and to minimize its negative impacts. Using data from 2528 households across the Indo-Gangetic Plains in India, Nepal, and Bangladesh, this study examines the factors affecting farmers’ use of organic and inorganic fertilizers for the two most important cereal crops – rice and wheat. Together, these crops provide the bulk of calories consumed in the region. As nitrogen (N) fertilizer is the major source of global warming and other environmental effects, we also examine the factors contributing to its overuse. We applied multiple regression models to understand the factors influencing the use of inorganic fertilizer, Heckman models to understand the likelihood and intensity of organic fertilizer (manure) use, and a probit model to examine the over-use of N fertilizer. Our results indicate that various socio-economic and geographical factors influence the use of organic and inorganic fertilizers in rice and wheat. Across the study sites, N fertilizer over-use is the highest in Haryana (India) and the lowest in Nepal. Across all locations, farmers reported a decline in manure application, concomitant with a lack of awareness of the principles of appropriate fertilizer management that can limit environmental externalities. Educational programs highlighting measures to improving nutrient-use-efficiency and reducing the negative externalities of N fertilizer over-use are proposed to address these problems.
Mostrar más [+] Menos [-]Factors affecting farmers’ use of organic and inorganic fertilizers in South Asia Texto completo
2021
Aryal, J.P. | Sapkota, T. | Krupnik, T.J. | Rahut, D.B. | Jat, M.L. | Stirling, C.
Fertilizer, though one of the most essential inputs for increasing agricultural production, is a leading cause of nitrous oxide emissions from agriculture, contributing significantly to global warming. Therefore, understanding factors affecting farmers’ use of fertilizers is crucial to develop strategies to improve its efficient use and to minimize its negative impacts. Using data from 2528 households across the Indo-Gangetic Plains in India, Nepal, and Bangladesh, this study examines the factors affecting farmers’ use of organic and inorganic fertilizers for the two most important cereal crops – rice and wheat. Together, these crops provide the bulk of calories consumed in the region. As nitrogen (N) fertilizer is the major source of global warming and other environmental effects, we also examine the factors contributing to its overuse. We applied multiple regression models to understand the factors influencing the use of inorganic fertilizer, Heckman models to understand the likelihood and intensity of organic fertilizer (manure) use, and a probit model to examine the over-use of N fertilizer. Our results indicate that various socio-economic and geographical factors influence the use of organic and inorganic fertilizers in rice and wheat. Across the study sites, N fertilizer over-use is the highest in Haryana (India) and the lowest in Nepal. Across all locations, farmers reported a decline in manure application, concomitant with a lack of awareness of the principles of appropriate fertilizer management that can limit environmental externalities. Educational programs highlighting measures to improving nutrient-use-efficiency and reducing the negative externalities of N fertilizer over-use are proposed to address these problems. | 51480-51496
Mostrar más [+] Menos [-]Factors affecting farmers’ use of organic and inorganic fertilizers in South Asia Texto completo
2021
Aryal, Jeetendra Prakash | Sapkota, Tek Bahadur | Krupnik, Timothy J. | Rahut, Dil Bahadur | Jat, Mangi Lal | Stirling, Clare M.
Fertilizer, though one of the most essential inputs for increasing agricultural production, is a leading cause of nitrous oxide emissions from agriculture, contributing significantly to global warming. Therefore, understanding factors affecting farmers’ use of fertilizers is crucial to develop strategies to improve its efficient use and to minimize its negative impacts. Using data from 2528 households across the Indo-Gangetic Plains in India, Nepal, and Bangladesh, this study examines the factors affecting farmers’ use of organic and inorganic fertilizers for the two most important cereal crops – rice and wheat. Together, these crops provide the bulk of calories consumed in the region. As nitrogen (N) fertilizer is the major source of global warming and other environmental effects, we also examine the factors contributing to its overuse. We applied multiple regression models to understand the factors influencing the use of inorganic fertilizer, Heckman models to understand the likelihood and intensity of organic fertilizer (manure) use, and a probit model to examine the over-use of N fertilizer. Our results indicate that various socio-economic and geographical factors influence the use of organic and inorganic fertilizers in rice and wheat. Across the study sites, N fertilizer over-use is the highest in Haryana (India) and the lowest in Nepal. Across all locations, farmers reported a decline in manure application, concomitant with a lack of awareness of the principles of appropriate fertilizer management that can limit environmental externalities. Educational programs highlighting measures to improving nutrient-use-efficiency and reducing the negative externalities of N fertilizer over-use are proposed to address these problems.
Mostrar más [+] Menos [-]Microplastics in the insular marine environment of the Southwest Indian Ocean carry a microbiome including antimicrobial resistant (AMR) bacteria: A case study from Reunion Island Texto completo
2024
Sababadichetty, Loik | Miltgen, Guillaume | Vincent, Bryan | Guilhaumon, François | Lenoble, Véronique | Thibault, Margot | Bureau, Sophie | Tortosa, Pablo | Bouvier, Thierry | Jourand, Philippe
The increasing threats to ecosystems and humans from marine plastic pollution require a comprehensive assessment. We present a plastisphere case study from Reunion Island, a remote oceanic island located in the Southwest Indian Ocean, polluted by plastics. We characterized the plastic pollution on the island's coastal waters, described the associated microbiome, explored viable bacterial flora and the presence of antimicrobial resistant (AMR) bacteria. Reunion Island faces plastic pollution with up to 10,000 items/km2 in coastal water. These plastics host microbiomes dominated by Proteobacteria (80 %), including dominant genera such as Psychrobacter, Photobacterium, Pseudoalteromonas and Vibrio. Culturable microbiomes reach 107 CFU/g of microplastics, with dominance of Exiguobacterium and Pseudomonas. Plastics also carry AMR bacteria including β-lactam resistance. Thus, Southwest Indian Ocean islands are facing serious plastic pollution. This pollution requires vigilant monitoring as it harbors a plastisphere including AMR, that threatens pristine ecosystems and potentially human health through the marine food chain.
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