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Perfluorinated and chlorinated pollutants as predictors of demographic parameters in an endangered seabird Полный текст
2008
Bustnes, Jan Ove | Erikstad, Kjell Einar | Lorentsen, Svein-Håkon | Herzke, Dorte
Despite global occurrence of several perfluorinated compounds (PFCs) the potential ecological effects of such substances on natural populations are not known. In endangered lesser black-backed gulls (Larus fuscus fuscus) on the Norwegian Coast, the blood concentrations of PFCs were as high as legacy organochlorines (OCs), and here we examined whether PFCs show associations similar to those of OCs to factors potentially affecting population growth, by evaluating relationships between contaminant concentrations and demographic parameters (reproductive performance and the probability of adults returning between breeding seasons). PFCs were not adversely associated with demographic parameters, while the most persistent OCs; notably PCB and p,p′-DDE, were adversely associated with early chick survival, and adult return rate. This study thus suggests that when the concentrations of PFCs and OCs are of similar magnitude in a gull population, OCs are more likely to cause adverse ecological effects. When the concentrations of PFCs and OCs are of similar magnitude in a population of gulls, OCs seem to have a stronger propensity for causing adverse ecological effects.
Показать больше [+] Меньше [-]Kosetice, Czech Republic – ten years of air pollution monitoring and four years of evaluating the origin of persistent organic pollutants Полный текст
2008
Dvorska, Alice | Lammel, Gerhard | Klánová, Jana | Holoubek, Ivan
The regional observatory Kosetice is a central European background station. Unique continuous monitoring from 1988 on is held here. POP (persistent organic pollutant) concentration values of air samples from Kosetice taken between 1996 and 2005 were statistically processed. Values of Czech ambient air quality standards were not exceeded. Concentrations of polycyclic aromatic hydrocarbons reached two maxima, in 1996 and 2001–2002. Polychlorinated biphenyls concentrations reached the highest values in 1997 and 1998 and hexachlorocyclohexanes concentrations in 1998. DDTs, hexachlorobenzene and pentachlorobenzene were analysed as well. Long-range transport of pollutants between 2002 and 2005 was evaluated using the Potential Source Contribution Function hybrid receptor model. Indicated potential source areas of PCBs coincide with many well-known urban and industrialised areas, while the indicated potential source areas of HCHs and DDTs coincide with many agricultural and/or forested regions and the potential source areas of HCB comprise all land use types. Source areas of organochlorinated pesticides used in agriculture are similar to each other, but different from the source areas of industrial polychlorinated biphenyls.
Показать больше [+] Меньше [-]Treatment of septage in sludge drying reed beds : a case study on pilot-scale beds Полный текст
2008
Troesch, S. | Liénard, A. | Molle, Pascal | Merlin, Gerard | Esser, D. | Qualité des eaux et prévention des pollutions (UR QELY) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | SOCIETE D'INGENIERIE NATURE ET TECHNIQUE AIX LES BAINS FRA ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]MA [TR1_IRSTEA]TED / EPURE | International audience | French legislation requires, the control of private on-site sanitation systems by local authorities. This will result in a large increase of the quantity of sludge from septic tanks to be treated. Nevertheless, large wastewater treatment plants are not systematically able to treat this sludge because they may have reached their nominal load or they are not so numerous in rural zone to avoid too long transportation. The study concerns both, the feasibility of sludge reed beds devoted to the treatment of septage and the assessment of a simultaneous treatment with aerated sludge. The experiments have been carried out on eight pilot-scale drying reed beds (2m²) planted with Phragmites australis. Two filtration layers of either vegetal compost or sand were tested. The study is focused on the commissioning period (first vegetative year) with a loading rate of 30 kgSS.m-2.yr-1. According to these operational conditions, dewatering efficiencies reached approx. 30% DM during summer but less than 20%DM in winter for each filtration layer and sludge. High removal efficiencies, with an average of 96%, 92% and 89% for SS, COD and TKN respectively, were achieved with septage whereas they were lower for the mixture of aerated sludge and septage. The dewaterability of septage and its filtration behaviour were assessed by several parameters (Capillary Suction Time, bound water) which may be some interesting tools for an optimised loading strategy.
Показать больше [+] Меньше [-]Sludge drying reed beds : a full and pilot-scales study for activated sludge treatment Полный текст
2008
Troesch, S. | Liénard, A. | Molle, Pascal | Merlin, Gerard | Esser, D. | Qualité des eaux et prévention des pollutions (UR QELY) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | SOCIETE D'INGENIERIE NATURE ET TECHNIQUE AIX LES BAINS FRA ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]MA [TR1_IRSTEA]TED / EPURE | International audience | Sludge drying reed beds have been used for dewatering and mineralization of sludge since the beginning of the 90's, but their insufficient performances in terms of Dry Matter [DM] content and mineralization of the sludge have made necessary new studies. Therefore, 8 pilots of 2m² each and a full-scale plant (13 000 p.e , 8 beds of 470m² in operation for 4 years) have been monitored to examine the influence of the sludge loading rate, the sludge quality and the loading frequency on the dewatering and mineralization efficiencies. Two filtration layers and two loading rhythms were tested on pilots which were fed at a loading rate of 25-30 kgDM.m-2.yr-1 during the first year of operation (commissioning period). Hydraulic behaviour (infiltration rate, outflow), O2 and CO2 relative concentrations in the filtration media, redox potential, pollutants removal and dry matter content were assessed during all the study. The rheological quality of the extracted sludge from full scale beds was assessed and showed that its mechanical behaviour exceed those of sludge of comparable dry matter content, making its spreading easier. Therefore, these sludge could easily claim the status of solid and stabilized sludge according to the French regulation. Design and management recommendations (number of beds, loading rates, feeding/rest period) gained from the experiments results are suggested.
Показать больше [+] Меньше [-]Field comparison of disjunct and conventional eddy covariance techniques for trace gas flux measurements Полный текст
2008
Rinne, J. | Douffet, T. | Prigent, Y. | Durand, P.
A field intercomparison experiment of the disjunct eddy covariance (DEC) and the conventional eddy covariance (EC) techniques was conducted over a grass field. The half-hourly water vapor fluxes measured by the DEC were within the estimated uncertainty from the fluxes measured by the EC. On the average there was a slight overestimation (<10%) of the fluxes measured by the DEC during the day and underestimation during the night as compared to the fluxes measured by the EC. As this bias does not appear in the simulated DEC measurements it is likely to be due to instrumental problems. The insensitivity of the quality of the fluxes measured by the DEC method to the deficiencies in the gas analysis shows the robustness of this new approach for measuring the surface-atmosphere exchange of trace gases. Results from the first field intercomparison between a new state-of-the-art trace gas flux measurement technique and the direct eddy covariance measurements are reported in this paper.
Показать больше [+] Меньше [-]Bulk deposition of polycyclic aromatic hydrocarbons (PAHs) in an industrial site of Turkey Полный текст
2008
Esen, F. | Cindoruk, S.S. | Tasdemir, Y.
Ambient air and deposition samples were collected in the period of July 2004-May 2005 in an industrial district of Bursa, Turkey and analyzed for polycyclic aromatic hydrocarbon (PAH) compounds. The overall average of fourteen bulk deposition fluxes for PAHs was 3300 ± 5100 ng m-2 d-1. PAH depositions showed a seasonal variation and they were higher in winter months. This was probably due to increases in residential heating activities and decreases in atmospheric mixing layer levels. Ambient air samples, measured with a high volume air sampler, were collected from the same site. The average total concentration including gas and particulate phase was about 300 ± 420 ng m-3 and it was in the range of previously reported values. Some of the ambient air and bulk deposition samples were collected simultaneously in dry periods. Both concurrently measured values were used to calculate the dry deposition velocities whose overall average value was 0.45 ± 0.35 cm s-1. Bulk deposition fluxes of PAHs were measured in an industrial area and deposition velocities of PAHs were reported.
Показать больше [+] Меньше [-]The application of a weight of evidence approach to compare the quality of coastal sediments affected by acute (Prestige 2002) and chronic (Bay of Algeciras) oil spills Полный текст
2008
Morales-Caselles, Carmen | Riba, Inmaculada | Sarasquete, Carmen | DelValls, T Ángel
The application of a weight of evidence approach to compare the quality of coastal sediments affected by acute (Prestige 2002) and chronic (Bay of Algeciras) oil spills Полный текст
2008
Morales-Caselles, Carmen | Riba, Inmaculada | Sarasquete, Carmen | DelValls, T Ángel
To evaluate sediment quality in different areas affected by oil spills, a weight of evidence approach was employed by including a complete set of parameters as part of four lines of evidence: sediment contamination, biological effects (including biomarkers) and bioaccumulation under laboratory conditions, toxicity in field conditions and benthic community structure. The methodology was applied to sediments from the Bay of Algeciras (S Spain) chronically impacted by different spills, and the Galician Coast (NW Spain) acutely impacted by an oil spill (Prestige 2002). Results obtained have elucidated the sources and fates of pollutants and the type of risk involved for the ecosystem. Factorial analysis revealed that the main factors were those containing toxicity, chemistry and benthic community variables indicating degradation in Algeciras. It has been demonstrated that the impact associated with chronic event of contamination by oil spills are significantly more dangerous and polluted than those related to acute effects. Chronic inputs due to the continuous entrance of contaminants result in much more harm to coastal ecosystems than major but precise environmental impacts.
Показать больше [+] Меньше [-]The application of a weight of evidence approach to compare the quality of coastal sediments affected by acute (Prestige 2002) and chronic (Bay of Algeciras) oil spills Полный текст
2008
Morales-Caselles, Carmen | Riba, Inmaculada | Sarasquete, Carmen | Del Valls, T. A.
To evaluate sediment quality in different areas affected by oil spills, a weight of evidence approach was employed by including a complete set of parameters as part of four lines of evidence: sediment contamination, biological effects (including biomarkers) and bioaccumulation under laboratory conditions, toxicity in field conditions and benthic community structure. The methodology was applied to sediments from the Bay of Algeciras (S Spain) chronically impacted by different spills, and the Galician Coast (NW Spain) acutely impacted by an oil spill (Prestige 2002). Results obtained have elucidated the sources and fates of pollutants and the type of risk involved for the ecosystem. Factorial analysis revealed that the main factors were those containing toxicity, chemistry and benthic community variables indicating degradation in Algeciras. It has been demonstrated that the impact associated with chronic event of contamination by oil spills are significantly more dangerous and polluted than those related to acute effects. Chronic inputs due to the continuous entrance of contaminants result in much more harm to coastal ecosystems than major but precise environmental impacts. | The work described was partly supported by the projects VEM2003-20563/INTER, and CTM2005-07282-C03-01/TECNO financed by the Spanish Education and Science Ministry and by CIS funded by the Ministry of Environment. C.M.-C. thanks the Ministry of Education and Science for funding her research fellowship (FPU). | Peer reviewed
Показать больше [+] Меньше [-]Simultaneous monitoring of profiles of polycyclic aromatic hydrocarbons in contaminated air with semipermeable membrane devices and spruce needles Полный текст
2008
Zhu, Xiuhua | Pfister, Gerd | Henkelmann, Bernhard | Kotalik, Jarmila | Bernhöft, Silke | Fiedler, Stefan | Schramm, Karl-Werner
Gaseous emissions of combusted electronic scrap, PVC, carpet and wood were monitored for polycyclic aromatic hydrocarbons (PAHs) by simultaneous use of semipermeable membrane devices (SPMDs) and shoots of spruce needles (Picea abies). It was found that phenanthrene, acenaphthylene and fluorene were the dominating PAHs in all samples. SPMDs and needles mainly sequestered PAH associated with the vapor phase. Particle-bound PAHs were only detected in small amounts, at which the needles tended to uptake more of these compounds in comparison to the SPMDs. Nevertheless, the logarithm of the concentrations of PAHs analyzed in both passive samplers after the same sampling period exhibited a significant linear correlation with correlation coefficients larger than 0.8073. SPMDs and spruce needles can complement each other in passive air sampling for compounds with a preference to the gas phase rather than aerosols.Relationship of PAHs in SPMDs and spruce needles at the same sampling time was found.
Показать больше [+] Меньше [-]Effects of prevalent freshwater chemical contaminants on in vitro growth of Escherichia coli and Klebsiella pneumoniae Полный текст
2008
Higgins, J. | Hohn, C.
Many surface and ground waters in the continental US are contaminated with a variety of chemical pollutants, which are usually present in concentrations in the ppm and ppb range. The effects of these pollutants on coliform bacteria, which are prominent members of the aquatic flora, are poorly understood. Using a microtiter plate assay, isolates of Escherichia coli (from chicken intestine and fresh water), and an isolate of Klebsiella pneumoniae (from bovine milk) were exposed to varying concentrations of common pollutants over a 24 h period. The herbicides/pesticides simazine, atrazine, and diazinon; the VOCs trichloroethene and MTBE; the estrogens estradiol and estrone; and caffeine, all failed to inhibit bacterial growth at ppm levels. Only ethylene glycol, and the herbicide 2,4-D, significantly inhibited bacterial growth compared to controls. These results suggest that the replication of coliform bacteria in fresh waters is not adversely impacted by many common pollutants. Using a microtiter plate assay, E. coli and Klebsiella bacteria were exposed to a panel of common chemical pollutants of fresh water; only ethylene glycol and 2,4-D inhibited bacterial replication.
Показать больше [+] Меньше [-]Ozone distribution and phytotoxic potential in mixed conifer forests of the San Bernardino Mountains, southern California Полный текст
2008
Bytnerowicz, Andrzej | Arbaugh, M (Michael) | Schilling, Susan | Frączek, Witold | Alexander, Diane
In the San Bernardino Mountains of southern California, ozone (O(3)) concentrations have been elevated since the 1950s with peaks reaching 600 ppb and summer seasonal averages >100 ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O(3) concentrations decreased with peaks approximately 180 ppb and approximately 60 ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O(3) concentrations (2-week averages) for individual years were much higher in western sites (58-69 ppb) than eastern sites (44-50 ppb). Potential O(3) phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5 ppmh, SUM60 - 112.7 ppmh, W126 - 98.3 ppmh, and AOT40 - 75 ppmh, representing the highest values reported for mountain areas in North America and Europe.
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