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Critical loads of acidity for France: consequences on forest ecosystems | Charges critiques d'acidité en polluants atmosphériques en France : conséquences vis-à-vis des sols et des peuplements forestiers
2001
Party, J.P. ((Sol-Conseil, Strasbourg (France))) | Probst, A. | Thomas, A.L. | Dambrine, E.
Depuis plus de 10 ans, les charges critiques ont été à la base des négociations internationales pour la réduction de la pollution atmosphérique. Les calculs de charges critiques d'acidité reposent sur l'estimation d'un flux de cations issu de l'altération des minéraux du sol et de la roche et sur un drainage acceptable de protons et d'aluminium. Les charges critiques d'acidité ont été calculées puis cartographiées au 1/1 000 000 pour les écosystèmes forestiers français. La carte obtenue résulte de la combinaison de données pédologiques, géochimiques, climatiques et de données minéralogiques extrapolées à partir d'un nombre limité de sites de référence (issus entre autres du réseau RENECOFOR). Pour la France, les charges critiques d'acidité sont faibles (moins de 1,0 keq/ha/an) pour moins de 15 pour cent des forêts françaises de production, soit 17 000 km2. Les surfaces où les charges critiques sont dépassées se situent principalement dans le nord-est de la France : Vosges, Ardennes, et dans une moindre mesure dans le sud-ouest de l'Ile-de-France et le long des bordures du Massif central, en Bretagne et en Normandie
Mostrar más [+] Menos [-]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 [-]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 [-]Calculation of Terrestrial Inputs to Particulate Organic Carbon in an Anthropogenically Impacted Estuary in the Southeastern United States Texto completo
2001
Eddins, Stefka G Nikolova
Using ¹³C/¹²C ratios in particulate organic carbon(POC), this study evaluated the fraction of terrestrially derivedPOC in Winyah Bay, South Carolina, an anthropogenically impactedestuary in the southeastern United States. Results from themixing model, which should be viewed as an upper limit becauseof possible dilution from additional potential end-members,showed that between 50 and 90% of POC in the Winyah Bay estuaryis of terrestrial origin. As this POC may be associated withriver-transported pollutants, the potential for accumulation ofpollutants in Winyah Bay is high because POC may become trappedin the estuary as part of either estuarine bottom sediments,circulation or food webs. Thus strategies for pollutionmonitoring and control in the estuary and its watershed arenecessary for the future management of Winyah Bay naturalresources.
Mostrar más [+] Menos [-]An organizational guide to pollution prevention Texto completo
2001
Atmospheric Bronze and Copper Corrosion as an Environmental Indicator. A Study Based on Chemical and Sulphur Isotope Data Texto completo
2001
Nord, A. G. | Tronner, K. | Boyce, A. J.
Corrosion products have been takenfrom 130 copper or bronze outdoor objects all overEurope. Their chemical composition and crystalsymmetry have been determined by means of scanning electron microscopy (SEM/EDS) and X-ray powderdiffraction. Data on location, sampling, objectcharacteristics, general environment and air pollutionlevel; type, colour and chemical composition of thecorrosion layers have been obtained and evaluated by multivariate statistical analysis. The resultsverify that the highest air pollution levels are usually associated with the occurrence of thick,black or dark grey corrosion layers on copper orbronze objects, preferentially containing soot, ironoxide hydroxides, and antlerite,Cu₃(SO₄)(OH)₄. Pale green corrosionusually contains brochantite,Cu₄(SO₄)(OH)₆, and is rather associatedwith less polluted areas. Atacamite, a copper hydroxide chloride with the chemical formula Cu₂Cl(OH)₃, is preferentially observed in coastal regions.In addition, sulphur isotope analyses have beenperformed on eleven corrosion samples from citycenters. The δ³⁴S values are typically inthe region from +4 to +6‰ relative to the sulphurisotope standard CDT (Canyon Diablo Troilite) with amean value of 4.7±1.2 (1σ), therebyindicating that the sulphur in the corrosion layers,in the form of brochantite or antlerite, mainlyoriginates from a similar source despite geographicvariation, most likely sulphur contained in air pollutants.
Mostrar más [+] Menos [-]Element Concentrations in Soils and Plant Bioindicators in Selected Habitats of the Holy Cross Mountains, Poland Texto completo
2001
Migaszewski, Zdzisław M. | Gałuszka, Agnieszka | Świercz, Anna | Kucharzyk, Jarosław
The objectives of this investigation in the HolyCross Mountain region of Poland were (1) to determineconcentration ranges and (2) mobility of elements within fivedetailed soil profiles and their apparent impact on thechemistry of some plant bioindicators, i.e. lichen thalli ofthe species Hypogymnia physodes (L.) Nyl. and Scotspine (Pinus sylvestris L.) bark. The results ofelemental determinations performed on soils and vegetationfrom the Holy Cross Mts show that some concentrations ofelements are elevated primarily due to air pollution.However, since 1994 a steady decrease in the content of S andsome heavy metals has been recorded in all the mediaexamined. Concentrations of many elements in H.physodes thalli and P. sylvestris needles of the Holy Cross Mountains are generally similarto those in other areas of Europe.
Mostrar más [+] Menos [-]Comparison of Odor Emissions from Three Different Biosolids Applied to Forest Soil Texto completo
2001
Rosenfeld, Paul E. | Henry, Charles L. (Charles Lee) | Dills, Russell L. | Harrison, Rob B.
The odor emissions from three types of biosolidsfrom King County, WA, were measured usingdilution-to-threshold olfactometry and mass spectralanalyses. This article describes thermal desorption andcryogenic GC/MS methods developed to characterizeodorant emissions from biosolids application to forestsoil. The major odorous compounds volatilized from twoanaerobically digested biosolids were ammonia anddimethyl disulfide, with lesser quantities of carbondisulfide, dimethyl sulfide, trimethyl amine, acetoneand methyl ethyl ketone. A third type of biosolidswas formed by centrifuge and drying one of the otherbiosolids at 190 °C. This dry biosolids producedmore odor and volatilized a more complex array ofvolatile compounds including: dimethyl disulfide,dimethyl sulfide, carbon disulfide, methylethyldisulfide, methane thiol, trimethyl amine, aceticacid, propionic acid, and butyric acid. Odor unitemissions were not found to correlate with microbialactivity, initial biosolids ammonium, organicnitrogen, and total sulfur. Variability in odoremission were explained by the number of odorouscompounds volatilized from each material, surface areaof biosolids and drying of the biosolids.
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