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Integrated pollution control | Umweltschutztechnik. English
1998
Förstner, Ulrich
Sustainable development and pollution control are the key factors in the development of strategies for the solution of environmental problems. This book offers an integrated treatment of all aspects of environmental protection and remediation. The presentation encompasses physical and chemical fundamentals, technological approaches as well as ecological, economic, and ethical aspects. The discussion of regulatory issues includes a comparison of environmental legislation in the US, Japan, and Europe. The book addresses students as a comprehensive text and serves as a handy reference for environmental professionals in industry, consulting services, administration, and environmental agencies and associations.
Afficher plus [+] Moins [-]Polycyclic Aromatic Hydrocarbons in the Sediments of the Milwaukee Harbor Estuary, Wisconsin, U.S.A Texte intégral
1998
Li, An | Ab Razak, Irwan A. | Ni, Fan | Gin, Michael F. | Christensen, Erik R.
From 1990 to 1994, a total of 21 sediment cores and 37 grab sediment samples were collected from the Milwaukee Harbor Estuary. Each sediment core was sectioned and dated using ²¹⁰Pb and¹³⁷ Cs radioisotope techniques. A total of 305 samples were analyzed for sixteen polycyclic aromatic compounds (PAHs). Grain size distribution, porosity, and total organic carbon content as measured by loss on ignition were also determined. The results provide a historical overview of the impact of industrialization in the Milwaukee area. Although highly variable, the concentration profile of PAHs show, in general, peaks in the 1950's through 1980's. The PAH concentrations have declined since then for most sediment cores. The current levels of total PAHs in most surface sediment samples range from 25 to 200 ppm. A few cores, some of which were collected in 1994, have an elevated PAH concentration at the surface. Toxicity of the surface sediments was evaluated by comparing with the benchmark values developed by the United States National Oceanic and Atmospheric Administration (NOAA). The most heavily contaminated area was found in the Kinnickinnic River between the Becher Street Bridge and the Wisconsin Wrecking Company Wharf. The highest total PAH concentration determined from seven vibra cores collected in this area ranges from 380 to 1000 ppm. The former Wisconsin Solvay Coke Company may have been a major point source of PAHs until the 1970's. Highway traffic and various industrial discharges also contribute to the sediment PAHs in this area.
Afficher plus [+] Moins [-]Geographic Classification of Heavy Metal Concentrations in Mosses and Stream Sediments in the Federal Republic of Germany Texte intégral
1998
Berlekamp, Jürgen | Herpin, Uwe | Matthies, Michael | Lieth, Helmut | Markert, Bernd | Weckert, Vera | Wolterbeek, H. Th. | Verburg, Tona | Zinner, Hans-Jürgen | Siewers, Ulrich
The results of the first German moss monitoring programme to estimate heavy metal pollution in the Federal Republic of Germany were combined with other large-scale investigations carried out in Germany and then classified geographically in a new form. Using Monte Carlo assisted factor analysis, six factors indicating sources of pollution were identified from the sets of element data from the moss monitoring project (As, Cd, Cr, Cu, Fe, Ni, Pb, Ti, V, Zn) and the data sets for SO₂ and particulate. The geographic distribution patterns of the factor values showed the regions in which the various sources are to be found. By combining the data the primarily anthropogenic chromium concentrations of the mosses were compared with the mainly geogenic chromium concentrations of the stream sediments in the form of examples. After normalization, the transformed chromium concentrations were transferred to a map of the entire area using inverse distance weighting. Anthropogenic and geogenic influences are being discussed on the basis of the results.
Afficher plus [+] Moins [-]On-line Analysis of Stack Gas Composition by a Low Resolution FT-IR Gas Analyzer Texte intégral
1998
Jaakkola, Petri T. | Vahlman, Tuula A. | Roos, Aappo A. | Saarinen, Pekka E. | Kauppinen, Jyrki K.
Stack gases of wood and oil burning boilers were analyzed by a low resolution FT-IR gas analyzer. Concentrations of carbon dioxide (CO₂), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO₂), nitrous oxide (N₂O), hydrogen cyanide (HCN), sulfur dioxide (SO₂), methane (CH₄), and water vapor (H₂O) were predicted in real time by multicomponent analysis. Detection limits, linearity, analysis accuracy and long time repeatability were experimentally determined for selected gas components. Applicability of the measurement method was demonstrated by analysis of stack gas mixtures of known concentrations. The results indicate that all the primary stack gas components can be measured by the low resolution FT-IR gas analyzer with comparable results to single component measurement methods.
Afficher plus [+] Moins [-]Assessment of Atmospheric Heavy Metals by Moss Monitoring with Isothecium Stoloniferum Brid. in the Fraser Valley, B.C., Canada Texte intégral
1998
Pott, Ute | Turpin, David H.
The atmospheric heavy metal pollution of the Fraser Valley, B.C., Canada was assessed in 1993 by analyzing 62 samples of the common woodland moss Isothecium stoloniferum for lead, cadmium, nickel, zinc, chromium, and manganese. The latter two metals did not show a distinct regional distribution, but lead, cadmium, nickel, and zinc showed distinct pattern along a west-east gradient. High values were found in the metropolitan Vancouver area, located in the west of the study region. Significantly lower values were recorded for mosses from the eastern more rural areas of the Fraser Valley. Metal pollutants are likely to be contained close to their emission sources by alternating south-east, north-west winds. Highest values overall were found in the North Shore Mountains, adjacent to Vancouver. This was related to higher precipitation and short range pollutant transport from the industrialized, heavily populated areas in the floodplain of the Fraser River.
Afficher plus [+] Moins [-]Effects of Afforestation on Acidity and Invertebrates in Danish Streams and Implications for Freshwater Communities in Denmark Texte intégral
1998
Friberg, Nikolai | Rebsdrof, Aage | Larsen, Søren
The relationship between acidity and benthic invertebrate communities was investigated in two small streams in coniferous forests in central Jutland, Denmark, during 1992 and 1993. Stream pH was acid (mean pH 4.8 and 5.4) and alkalinity fluctuated greatly with mean values around zero. During rain events, water from springfed reaches upstream were mixed downstream with brown humic acid water with high aluminium content, and pH declined from circumneutral near the springs down to pH below 4 over a very short distance (0.5–1.5 km). The benthic invertebrate communities in the most acidic downstream reaches of both streams were dominated by filipalpian stoneflies, mainly Leuctra nigra (Olv.). Community composition remained very similar throughout the sampling period despite variations in pH. In the upper (neutral) reaches invertebrates intolerant of low pH such as Gammarus pulex L. were found. The concentrations of chloride and sulphate in the streams were more than double the concentrations in a nearby moorland stream indicating a strong impact of acidifying atmospheric deposition on the two forest streams. Results of this study indicate that afforestation with conifers on sandy Danish soils with low buffering capacity (about 25% of the total Danish land area) may lead to an increased acidification of surface waters and thereby also to an impoverished aquatic fauna.
Afficher plus [+] Moins [-]Airborne Pollution in Five Drainage Basins in Eastern Finnmark, Norway: an Evaluation of Overbank Sediments as Sampling Medium for Environmental Studies and Geochemical Mapping Texte intégral
1998
Langedal, Marianne | Ottesen, Rolf Tore
To study whether airborne pollution can be detected in overbank sediments, samples collected from five overbank sediment profiles in eastern Finnmark, Norway, at 1 cm depth intervals, were subjected to chemical analysis and ²¹⁰Pb dating. The studied drainage basins constitute parts of an area polluted by emissions from two Ni-Cu smelters in Russia. In the most polluted catchment area, the surface sample showed a 5-fold higher Ni concentration and a 3-fold higher Cu concentration than the pre-industrial sediments at depth. The increases started at the same time as the smelters. Slight Ni increases were also detected in the neighbouring drainage basin, while no significant concentration change was seen in drainage basins previously shown to be only weakly influenced by the smelter emissions. In the most polluted drainage basin, the increase in Ni accumulation rate did not equal the airborne deposition rate. Selective surface erosion of fine grained particles with adhering airborne Ni has probably caused excess Ni accumulation in both overbank and lake sediments. On the contrary, opening of minerogenic point sources may dilute the pollutant concentrations in the drainage sediments. Thus, dating of the sediment profiles is necessary to determine the airborne pollutant accumulation rates. However, dating is not necessary to map the resultant concentration increase, that may show the increased exposure of humans and biota in contact with the sediments.
Afficher plus [+] Moins [-]An Emissions Inventory for Regional Atmospheric Modeling of Mercury Texte intégral
1998
Pai, Prasad | Heisler, S. (Steven) | Joshi, Aruna
Estimates of mercury emissions from individual sources and source categories are needed to understand relationships between the emissions and resulting deposition and to evaluate possible approaches to reducing those emissions. We have developed geographically-resolved estimates of annual average mercury emission rates from current anthropogenic sources in the 48 contiguous United States. These estimates were made by applying emission factors to individual facility operating data and to county-wide source activity levels. We apportioned the emissions to an Eulerian modeling grid system using point source coordinates and the fractions of county areas in each grid cell. Point sources account for about 89% of the 48-state total mercury emissions of 146.4 Mg/yr. Most of the emissions in the inventory are from combustion of mercury-containing fossil fuels and municipal waste, located primarily in the mid-Atlantic and Great Lakes states as well as in the Southeast. The major uncertainties in the emission estimates are caused by uncertainties in the emission factors used to develop the estimates. This uncertainty is likely a result of variability in the mercury content of the combusted materials and in the removal of mercury by air pollution control devices. The greatest research need to reduce uncertainties in mercury emission estimates is additional measurements to improve emission factors.
Afficher plus [+] Moins [-]Levels of selected chlorinated hydrocarbons in edible fish tissues from polluted areas in the Georges/Cooks Rivers and Sydney Harbour, New South Wales, Australia
1998
Roach, A.C. | Runcie, J. (Environment Protection Authority, New South Wales Locked Bag 1502, Bankstown, NSW 2200 (Australia))
UK national marine analytical quality control scheme: the assessment of performance in the determination of organochlorines in water, 1992-1996
1998
Law, R.J. | Dobson, J.E. (The Centre for Environment, Fisheries and Aquaculture Science, CEFAS Burnham Laboratory, Burnham-on-Crouch, Essex CMO 8HA (United Kingdom))