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Fluxes of heavy metals deposition on the snow of the French Alps during the 1997-1998 and 1998-1999 winter periods. Methodology and preliminary results
2001
Veysseyre, A. (Centre National de la Recherche Scientifique, Saint Martin d'Heres (France). Laboratoire de Glaciologie et Geophysique de l'Environnement) | Ferrari, C. | Elichegaray, C. | Ebner, P. | Boutron, C.
En 1997, le ministere de l'Amenagement du Territoire et de l'Environnement et l'Agence de l'environnement et de la maitrise se de l'energie (ADEME) ont commande au Laboratoire de Glaciologie et Geophysique de l'environnement de Grenoble (LGGE) (CNRS) une etude visant a evaluer les depots de metaux lourds dans les Alpes francaises en utilisant le manteau neigeux saisonnier comme piege des ces polluants pour les hivers 1997-1998 et 1998-1999. La neige est en effet un support interessant car elle ne permet pas d'interaction chimique avec les metaux. Contrairement aux mousses, ce support a donc l'avantage de permettre la determination du depot reel de ces metaux, parametre indispensable pour evaluer ulterieurement les niveaux superieurs aux charges critiques. Le domaine d'etude a ete delimite au massif alpin, car il fallait trouver un domaine de montagne ou l'on avait des altitudes suffisamment elevees (1500m) pour obtenir un manteau neigeux consequent pendant une assez longue periode. De plus, la region Rhone-Alpes est dotee de vallees fortement industrialisees, avec un fort trafic routier, ce qui va permettre de suivre, entre autres, des polluants traceurs ainsi que leur repartition spatiale, et les niveaux de contamination des Alpes. L'etendue du domaine d'etude a, en revanche, ete etablie selon des criteres pratiques. L'integralite du massif Alpin francais n'etait pas gerable, meme avec l'aide des parcs nationaux, regionaux et des reserves naturelles. Nous avons donc prefere mettre l'accent sur des analyses et interpretations plus poussees au sein de chaque massif plutot que sur une plus grande quantite de mailles donc des echantillons. Dans cet article est presentee toute la methodologie mise en place pour le choix des sites, les prelevements, les analyses. Des premiers resultats sont presentes sur certains massifs
Mostrar más [+] Menos [-]AgriBMPWater : approche de systèmes vers une culture respectueuse de l'environnement | AgriBMPWater: systems approach to environmentally acceptable farming Texto completo
2001
Laplana, R.
Rising concern about agricultural non-print water pollution has led to the proposal of many regulatory measures. Agri-environmental programmes have been implemented in the different EU Member States according to the Commission regulation 2078/92. Best management practices, one of the most popular tools, have rarely been assessed in a fully satisfying way. Therefore, the main objective of this project is to provide planners in charge of the implementation of BMPs in the field of combating diffusion pollution either at a national or local scale, with both a guideline allowing the definition of critical areas on which efforts should be place in priority, and a selection grid permitting the assessment of BMPs in a three-dimensional space defined by environmental effectiveness, associated economic costs and social acceptability by farmers and land managers. Expectedd results should contribute to help Member States choosing the most appropriate measures and ways for an efficient implementation of BMPs, with the support of scientifically validated technical and economic recommendations. | Le principal objectif de ce projet est de procurer aux acteurs responsables de la lutte contre la pollution diffuse grâce aux meilleures pratiques de gestion une échelle nationale ou locale qui indique les zones prioritaires et l'évaluation des méthodes par l'efficacité environnementale, les coûts économiques associés et l'acceptation sociale de la part des agriculteurs et des gestionnaires des terres.
Mostrar más [+] Menos [-]Agricultural nonpoint source pollution
2001
Ritter, William F. | Shirmohammadi, Adel
Bioreactors for waste gas treatment
2001
Kennes, C. | Veiga, M. C.
The treatment of polluted air by passing it through biological filters is proving more effective and less expensive than conventional physical and chemical technologies. This book overviews the major bioreactor designs currently available on the market. The first part explains the principles of the different techniques, followed by descriptions of full-scale bioreactor applications for each system. Topics of the 14 chapters include biotrickling filters, membrane bioreactors, rotating biological contactors, activated sludge, biofiltration of waste gases from a dairy industry, and a bioscrubber for cleaning waste gases from wastewater treatment plants. c. Book News Inc.
Mostrar más [+] Menos [-]Economic losses from marine pollution
2001
Ofiara, Douglas D. | Seneca, Joseph J.
Marine pollution causes significant damage to fisheries and other economically productive uses of the ocean. The value of that damage can be quantified by economists, but the meanings of those valuations and how they are derived are often obscure to noneconomists. Economic Losses from Marine Pollution brings a fuller understanding of the variety and extent of marine losses and how they are assessed to scientists, lawyers, and environmentalists by systematically identifying and classifying marine losses and relating them to models and methods of economic valuation. The authors use a step-by-step approach to show how economists have used these methods and how they approach the problem of assessing economic damage. The book begins by describing the importance of economic valuation of marine damages, the history of concern over marine pollution, and the development of economic methodologies to assess damage from it. Following that, the book: considers types of marine pollution and their effects on organisms, ecosystems, and humans, and the corresponding economic effects of those biological impacts introduces the economic principles and methods needed to understand and to assess economic damages expresses losses from water quality impairments in terms of economic value introduces the basic economic techniques that have been developed and used to measure changes in economic value discusses how to apply those economic techniques, and presents a variety of practical examples explores limitations and problems that can arise in such applied work. Economic Losses from Marine Pollution includes all of the relevant economic theory together with specific examples of how that theory has been and can be applied. It offers environmental professionals with little or no background in economics the basic economic tools needed to understand economic valuations of environmental damage. --Publisher.
Mostrar más [+] Menos [-]Rapid Mercury Analysis for the Field: Method Development and Application to Natural Gas Utility Sites Texto completo
2001
Boylan, Helen M. | Richter, Robert C. | Kingston, H. M ‘Skip’ | Ricotta, Angela
A new technique based on traditional concepts has beendeveloped for rapid, on-site analysis of mercury inenvironmental media. In this method, mercury isanalyzed by integration of thermal decomposition,amalgamation, and atomic absorption spectrometry(TDA-AAS). Sample preparation and analysis areessentially integrated into a single instrumentalsystem; solid samples can be analyzed directly,without chemical pre-treatment, in an analysis time ofapproximately 5 minutes per sample. A wide range ofstandard reference material has been analyzed byTDA-AAS. Agreement with the certified values at the95% confidence interval for all matrices testedvalidates this technique. Subsequent to validation,TDA-AAS has been used in a series of field studies inconjunction with remediation of mercury-contaminatedsoil at natural gas utility sites. Reasonableagreement has been demonstrated between TDA-AASon-site results and laboratory results usingconventional mercury analysis techniques. Independentlaboratory confirmation of the field data is notrequired as TDA-AAS demonstrates lab-quality resultson-site. This field technique has been shown tosurpass traditional laboratory methods in terms ofboth precision and detection limits. A method for theUnited States Environmental Protection Agency (USEPA), Method 7473, has been developed and validatedbased on TDA-AAS methodology (US EPA, 1998).
Mostrar más [+] Menos [-]Nitrous Oxide Emission from Soil with Different Fertilizers, Water Levels and Nitrification Inhibitors Texto completo
2001
Pathak, Himanshu | Nedwell, D. B.
The effects of urea, (NH₄)₂SO₄, KNO₃, and NH₄NO₃ on nitrous oxide (N₂O) emission from soil at field capacity and submerged condition were studied during 120 days in the laboratory. Soils in both moisture regimes gave higher emissions in the beginning, which were reduced later. Total emission of N₂O was higher at submergence as compared to field capacity regardless of fertilizer type. At field capacity soil fertilized with ureaemitted the highest amount of N₂O (1903 μg N₂O-N kg⁻¹ soil) during 120 days while at submerged condition, soil with NH₄NO₃ gave the highest emission (4843 μg N₂O-N kg⁻¹ soil). In another study, the efficacy of seven nitrification inhibitors in reducing the emission of N₂O-N from soil fertilized with urea was tested in the laboratory. Nitrapyrin, 2-amino-4-chloro-6-methylpyrimidine (AM), and dicyandiamide (DCD) reduced the emission to 12, 24, and 63% that of urea, respectively, whereas sodium thiosulphate, sulphur, acetylene,and thiourea had no effect on emission of N₂O. In submerged conditions none of the inhibitors reduced the emission.
Mostrar más [+] Menos [-]Environmental Impacts of Landfill Bioreactorcells in Comparison to Former Landfill Techniques Texto completo
2001
Binder, Michael | Bramryd, Torleif
Former and present landfill techniques at the Filbornaplant in Helsingborg, South Sweden are compared withrespect to impacts on the environment. This includes thepotential for nutrient recovery and heavy metalimmobilisation in the waste residue. The results showthat optimised landfill bioreactor-cells have a higherturn-over rate for organic matter compared to the formerlandfills, whereas the retention capacity for heavymetals in both systems was surprisingly high. Full scaleleachate data, as well as a laboratory leachingexperiments confirmed the role of bioreactor cells asanaerobic filters enabling a separation of nutrients froma mixed waste, while the toxic metals are retained. Theconclusion of this article is that by simple measures, thebiological processes can be optimised, resulting inhigher turn-over rates for organic matter and thusaccelerated waste stabilisation.
Mostrar más [+] Menos [-]A Note on Soil Erosion and Its Environmental Consequences in the United States Texto completo
2001
Uri, Noel D.
Soil erosion has both on-farm and off-farm impacts. Reduction ofsoil depth can impair the land's productivity, and the transportof sediments can degrade streams, lakes, and estuaries. Since1933, soil conservation policies have existed in the UnitedStates. Originally they focused on the on-farm benefits ofkeeping soil on the land and increasing net farm income.Beginning in the 1980s, however, policy goals increasinglyincluded reductions in off-site impacts of erosion. As aconsequence of conservation efforts associated with explicitU.S. government policies, total soil erosion between 1982 and1992 was reduced by 32% and the sheet and rill erosion ratefell from an average of 4.1 tons per acre per year in 1982 to 3.1 tons per acre in 1992. Wind erosion rate fell from anaverage of 3.3 tons per acre per year to 2.4 tons per acre peryear over the same period. Still, soil erosion is imposingsubstantial social costs. These costs are estimated to be about$37.6 billion annually. To further reduce soil erosion andthereby mitigate its social costs, there are a number of policyoptions available to induce farmers to adopt conservationpractices including education and technical assistance,financial assistance, research and development, land retirement,and regulation and taxes.
Mostrar más [+] Menos [-]Measurement of Volatile Organic Compounds in Urban Air of La Coruña, Spain Texto completo
2001
Fernández-Martínez, G. | López-Mahía, P. | Muniategui-Lorenzo, S. | Prada-Rodríguez, D. | Fernández-Fernández, E.
Twenty-eight volatile organic compounds have been measured in a 3-month monitoring campaign. The sampling point is locatedin the urban centre of La Coruña, a medium-size town in theNorthwest of Spain. Only a petrol refinery can be consideredas an important point VOCs source in its surrounding area.The municipal landfill collapsed in September 1996, and rebuilding works caused strong odour episodes at the urbancentre. We tried to check how this problem affected urban airquality. Samples were taken with Tenax-TA tubes and analysedby thermal desorption-GC-MS. From the results obtained, traffic emissions were recognised as the main VOCs source inthe sampling zone. On November 9th a contaminationepisode took place. Aromatic and aliphatic compounds levelswere probably affected by emissions from fuel treatmentprocesses in a nearby petrol refinery. No influence onquantified VOCs concentrations from the remaking landfillworks was observed. Several compounds (organosulphurs, estersand alcohols) were recognised as the cause of odour problems.
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