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Long-term biological monitoring of environmental quality around a solid waste landfill assessed with lichens Полный текст
2012
Paoli, L. | Corsini, A. | Bigagli, V. | Vannini, J. | Bruscoli, C. | Loppi, S.
The diversity of epiphytic lichens and the accumulation of selected trace elements in the lichen Flavoparmelia caperata L. (Hale) were used as indicators of pollution around a landfill in central Italy along 14 years of waste management. Lichens revealed an increased deposition for some elements (i.e., Cd, Cr, Fe and Ni) and a decrease of the lichen diversity at sites facing the landfill after an enlargement of the dumping area. However, the results allowed to exclude a significant increase in heavy metal depositions in the surrounding area and suggested that successful waste management may be associated with environmental quality. It is concluded that lichen monitoring might provide essential information to enhance the implementation of ecological impact assessment, supporting industrial regulatory procedures, also when waste management is concerned.
Показать больше [+] Меньше [-]Use of a Bayesian isotope mixing model to estimate proportional contributions of multiple nitrate sources in surface water Полный текст
2012
Xue, Dongmei | De Baets, Bernard | Van Cleemput, Oswald | Hennessy, Carmel | Berglund, Michael | Boeckx, Pascal
To identify different NO₃ ⁻ sources in surface water and to estimate their proportional contribution to the nitrate mixture in surface water, a dual isotope and a Bayesian isotope mixing model have been applied for six different surface waters affected by agriculture, greenhouses in an agricultural area, and households. Annual mean δ¹⁵N–NO₃ ⁻ were between 8.0 and 19.4‰, while annual mean δ¹⁸O–NO₃ ⁻ were given by 4.5–30.7‰. SIAR was used to estimate the proportional contribution of five potential NO₃ ⁻ sources (NO₃ ⁻ in precipitation, NO₃ ⁻ fertilizer, NH₄ ⁺ in fertilizer and rain, soil N, and manure and sewage). SIAR showed that “manure and sewage” contributed highest, “soil N”, “NO₃ ⁻ fertilizer” and “NH₄ ⁺ in fertilizer and rain” contributed middle, and “NO₃ ⁻ in precipitation” contributed least. The SIAR output can be considered as a “fingerprint” for the NO₃ ⁻ source contributions. However, the wide range of isotope values observed in surface water and of the NO₃ ⁻ sources limit its applicability.
Показать больше [+] Меньше [-]Factors regulating the bioavailability of methylmercury to breeding rusty blackbirds in northeastern wetlands Полный текст
2012
Edmonds, Samuel Trower | O'Driscoll, Nelson J. | Hillier, N Kirk | Atwood, Jonathan L. | Evers, David C.
Rusty blackbirds are undergoing rapid population decline and have elevated Hg concentrations while breeding in the Acadian ecoregion of North America. Factors regulating the bioavailability of methyl-Hg (MeHg) within this population's habitat were determined using water, invertebrates, and blood from adult rusty blackbirds collected for Hg-speciation, along with additional water column parameters: MeHg and THg, dissolved organic carbon, pH, dissolved oxygen, conductivity, redox potential, and temperature. Both DO₂ and pH were negatively related to biota MeHg, while water MeHg concentrations were positively related. Both invertebrate MeHg concentration and %MeHg increased with trophic level. Invertebrate MeHg concentrations were among the greatest reported when compared with those reported elsewhere for wetlands and waterbodies—often several times greater for similar taxa—while percent MeHg of THg were similar. An environment with high bioavailability of MeHg in combination with a high trophic position best explains elevated Hg concentrations for this species regional population.
Показать больше [+] Меньше [-]Polybrominated diphenyl ethers (PBDEs) in sediments of the coastal East China Sea: Occurrence, distribution and mass inventory Полный текст
2012
Li, Yuanyuan | Lin, Tian | Chen, Yingjun | Hu, Limin | Guo, Zhigang | Zhang, Gan
Polybrominated diphenyl ethers (PBDEs) of sixty-three sediment samples from the coastal East China Sea (ECS), extending ∼1000 km from the Yangtze River Estuary to the south, were measured. The levels of BDE-209 and ∑PBDE₇ (sum of BDE-28, 47, 99, 100, 153, 154, 183) were 0.3–44.6 ng/g (dry weight) and nd-8.0 ng/g, respectively. BDE-209 was the predominant congener, followed by BDE-99/100. This was consistent with the historical and current usage of PBDE mixtures in China. The compositions and distribution of PBDEs suggest that the PBDEs in this area could be mainly from the coastal electronic waste dismantling/recycling and Yangtze River input. The poor correlations between TOC, grain size of sediments with PBDEs imply that the PBDE distribution is more related to their land-based inputs rather than the sediment characters in the area. The coastal ECS is an important sink of PBDEs (7.5 t/yr) in the world.
Показать больше [+] Меньше [-]Environmental risks of trace elements associated with long-term phosphate fertilizers applications: A review Полный текст
2012
Jiao, Wentao | Chen, Weiping | Chang, Andrew C. | Page, Albert L.
Application of phosphate fertilizer can be a significant contributor of potentially hazardous trace elements such as arsenic, cadmium, and lead in croplands. These trace elements have the potential to accumulate in soils and be transferred through the food chain. We articulated the environmental risks of trace elements associated with long-term phosphate fertilizer applications by combining data from the literature and results from model simulations. Results illustrate that under normal cropping practice, the impact of phosphate fertilizers applications on trace element accumulation in receiving soils has been limited and localized. Their plant uptake varied greatly depending on the fertilizer application rates, soil and plant characteristics. This has led to a great deal of uncertainty in characterizing soil distribution coefficients, Kd, and plant uptake factors, PUF, two of the most used parameters in assessing the risks of accumulations. Therefore, the risks may be more appropriately assessed based on the probabilistic distributions of Kd and PUF.
Показать больше [+] Меньше [-]The impact of organochlorines cycling in the cryosphere on their global distribution and fate – 1. Sea ice Полный текст
2012
Guglielmo, Francesca | Stemmler, Irene | Lammel, Gerhard
Global fate and transport of γ-HCH and DDT was studied using a global multicompartment chemistry-transport model, MPI-MCTM, with and without a dynamic sea ice compartment. The MPI-MCTM is based on coupled ocean and atmosphere general circulation models. Sea ice hosts 7–9% of the burden of the surface ocean. Without cycling in sea ice the geographic distributions are shifted from land to sea. This shift of burdens exceeds the sea ice burden by a factor of ≈8 for γ-HCH and by a factor of ≈15 for DDT. As regional scale seasonal sea ice melting may double surface ocean contamination, a neglect of cycling in sea ice (in an otherwise unchanged model climate) would underestimate ocean exposure in high latitudes. Furthermore, it would lead to overestimates of the residence times in ocean by 40% and 33% and of the total environmental residence times, τₒᵥₑᵣₐₗₗ, of γ-HCH and DDT by 1.6% and 0.6%, respectively.
Показать больше [+] Меньше [-]Field assessment of a snap bean ozone bioindicator system under elevated ozone and carbon dioxide in a free air system Полный текст
2012
Burkey, Kent O. | Booker, Fitzgerald L. | Ainsworth, Elizabeth A. | Nelson, Randall L.
Ozone-sensitive (S156) and -tolerant (R123 and R331) genotypes of snap bean (Phaseolus vulgaris L.) were tested as a plant bioindicator system for detecting O₃ effects at current and projected future levels of tropospheric O₃ and atmospheric CO₂ under field conditions. Plants were treated with ambient air, 1.4× ambient O₃ and 550 ppm CO₂ separately and in combination using Free Air Concentration Enrichment technology. Under ambient O₃ concentrations pod yields were not significantly different among genotypes. Elevated O₃ reduced pod yield for S156 (63%) but did not significantly affect yields for R123 and R331. Elevated CO₂ at 550 ppm alone did not have a significant impact on yield for any genotype. Amelioration of the O₃ effect occurred in the O₃ + CO₂ treatment. Ratios of sensitive to tolerant genotype pod yields were identified as a useful measurement for assessing O₃ impacts with potential applications in diverse settings including agricultural fields.
Показать больше [+] Меньше [-]Size dependent bioaccumulation and ecotoxicity of gold nanoparticles in an endobenthic invertebrate: The Tellinid clam Scrobicularia plana Полный текст
2012
Pan, Jin-Fen | Buffet, Pierre-Emmanuel | Poirier, Laurence | Amiard-Triquet, C. | Gilliland, Douglas | Joubert, Yolaine | Pilet, Paul | Guibbolini, Marielle | Risso de Faverney, Christine | Roméo, Michèle | Valsami-Jones, Eugenia | Mouneyrac, Catherine
Gold nanoparticles (AuNPs) have important technological applications resulting in an increased potential for release to the environment, and a greater possibility of toxicological effects. The marine bivalve Scrobicularia plana was exposed to AuNPs of size 5, 15 and 40nm during a 16 d laboratory exposure at 100μg Au L⁻¹. After exposure to AuNPs forming aggregates (>700nm), the clams accumulated Au in their soft tissues. Biochemical (biomarkers) and behavioral (burrowing and feeding) responses were investigated. Au NPs were responsible of metallothionein induction (5, 40nm), increased activities of catalase (15, 40nm) and superoxide dismutase (40nm) and of glutathione S-transferase by the three sizes of AuNPs indicating defense against oxidative stress. Exposure to AuNPs impaired burrowing behavior. However, it must be underlined that these effects were observed at a dose much higher than expected in the environment.
Показать больше [+] Меньше [-]Ozone weekend effect in Santiago, Chile Полный текст
2012
Seguel, Rodrigo J. | Morales S., Raúl G.E. | Leiva G., Manuel A.
The study examined weekday–weekend differences in ozone, NOₓ (NO and NO₂) and VOC concentrations in Santiago, Chile, from 1999 to 2007. The results provide evidence for the occurrence of an atmospheric phenomenon that produces higher ozone concentrations during weekends despite lower concentrations of ozone precursors. This phenomenon is known as the weekend effect (WE). The overall ozone decrease since the spring of 2004 was a consequence of the implementation of several urban pollution control measures. Although these measures caused a decline in the number of days that exceed the national standard from two-thirds to one-third of summer days, the WE, which became statistically significant beginning in September 2004, could not be eliminated. Furthermore, VOC/NOₓ ratios decreased during the same period (2004), especially in the most industrialized area of Santiago. Similarly, under these regimes, the VOC/NOₓ ratios were higher on Sundays than on weekdays and caused higher ozone concentrations on Sundays.
Показать больше [+] Меньше [-]Polybrominated diphenyl ethers (PBDEs) in the indoor and outdoor environments – A review on occurrence and human exposure Полный текст
2012
Besis, Athanasios | Samara, Constantini
Polybrominated diphenyl ethers (PBDEs) constitute an important group of brominated flame retardants that have been massively produced and extensively used in numerous everyday products, providing longer escape times in case of fire and thus saving lives, as well as reducing the damage of property. In recent years, PBDEs have been recognized as significant pollutants of the indoor environment. This article provides a synthesis and critical evaluation of the state of the knowledge about the occurrence of PBDEs in the indoor environment (air and dust in homes, workplaces and cars) in different countries in Europe, North America, Asia and Australia, as well as about the human exposure via indoor air inhalation and dust ingestion in comparison to outdoor air inhalation and dietary intake.
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