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Changes in bioaccumulation and translocation patterns between root and leafs of Avicennia schaueriana as adaptive response to different levels of metals in mangrove system 全文
2015
Souza, Iara da C. | Rocha, Lívia D. | Morozesk, Mariana | Bonomo, Marina M. | Arrivabene, Hiulana P. | Duarte, Ian D. | Furlan, Larissa M. | Monferrán, Magdalena V. | Mazik, K. (Krysia) | Elliott, Michael | Matsumoto, Silvia T. | Milanez, Camilla R.D. | Wunderlin, Daniel A. | Fernandes, Marisa N.
Espírito Santo estuaries (Brazil) are impacted by industrial activities, resulting in contamination of water and sediments. This raise questions on biological uptake, storage and consequences of metal contamination to mangrove plants. The goal of this work was evaluating accumulation and translocation of metals from sediment to roots and leaves of Avicennia schaueriana, growing in areas with different degrees of contamination, correlating bioaccumulation with changes in its root anatomy. Highest bioconcentration factors (BCFs) were observed in plants growing in less polluted areas. Conversely, highest translocation factors were found in plants from highest polluted area, evidencing an adaptive response of A. schaueriana to less favourable conditions. Namely, the absorption of metals by roots is diminished when facing highest levels of metals in the environment; alternatively, plants seem to enhance the translocation to diminish the concentration of toxic metals in roots. Root also responded to highly polluted scenarios with modifications of its anatomy.
显示更多 [+] 显示较少 [-]Experimental assessment of critical anthropogenic sediment burial in eelgrass Zostera marina 全文
2015
Munkes, Britta | Schubert, Philipp R. | Karez, Rolf | Reusch, Thorsten B.H.
Seagrass meadows, one of the world's most important and productive coastal habitats, are threatened by a range of anthropogenic actions. Burial of seagrass plants due to coastal activities is one important anthropogenic pressure leading to the decline of local populations. In our study, we assessed the response of eelgrass Zostera marina to sediment burial from physiological, morphological, and population parameters. In a full factorial field experiment, burial level (5–20cm) and burial duration (4–16weeks) were manipulated. Negative effects were visible even at the lowest burial level (5cm) and shortest duration (4weeks), with increasing effects over time and burial level. Buried seagrasses showed higher shoot mortality, delayed growth and flowering and lower carbohydrate storage. The observed effects will likely have an impact on next year's survival of buried plants. Our results have implications for the management of this important coastal plant.
显示更多 [+] 显示较少 [-]Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia 全文
2015
Maes, Christophe | Blanke, Bruno
Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia 全文
2015
Maes, Christophe | Blanke, Bruno
Contamination of the marine environment by human-made plastic litter is a growing and global problem. Our study attempts to explain the presence of two plastic bottles beached on the Ouvéa Island, in the southwest Pacific Ocean, with trademarks from the Solomon Islands and Papua New Guinea (PNG). We simulate the oceanic drift tracks and associated transit times with a Lagrangian interpretation of the surface currents of a high-resolution ocean model. Our results show that it takes less than 2–3 months for drifting objects to connect these archipelagos (New Caledonia, Solomon Islands and PNG) and highlight the role of the meridional component of the circulation rather than the dominant zonal jets. This study shows that the origin or traceability of trash represent valuable information that can be used to test and, ultimately, improve our understanding of ocean circulation.
显示更多 [+] 显示较少 [-]Tracking the origins of plastic debris across the Coral Sea: A case study from the Ouvéa Island, New Caledonia 全文
2015
Maes, Christophe | Blanke, Bruno
Contamination of the marine environment by human-made plastic litter is a growing and global problem. Our study attempts to explain the presence of two plastic bottles beached on the Ouvéa Island, in the southwest Pacific Ocean, with trademarks from the Solomon Islands and Papua New Guinea (PNG). We simulate the oceanic drift tracks and associated transit times with a Lagrangian interpretation of the surface currents of a high-resolution ocean model. Our results show that it takes less than 2–3months for drifting objects to connect these archipelagos (New Caledonia, Solomon Islands and PNG) and highlight the role of the meridional component of the circulation rather than the dominant zonal jets. This study shows that the origin or traceability of trash represent valuable information that can be used to test and, ultimately, improve our understanding of ocean circulation.
显示更多 [+] 显示较少 [-]Exposure to vancomycin causes a shift in the microbial community structure without affecting nitrate reduction rates in river sediments 全文
2015
Laverman, Anniet M. | Cazier, Thibaut | Yan, Chen | Roose-Amsaleg, Céline | Petit, Fabienne | Garnier, Josette | Berthe, Thierry
Exposure to vancomycin causes a shift in the microbial community structure without affecting nitrate reduction rates in river sediments 全文
2015
Laverman, Anniet M. | Cazier, Thibaut | Yan, Chen | Roose-Amsaleg, Céline | Petit, Fabienne | Garnier, Josette | Berthe, Thierry
International audience | Antibiotics and antibiotic resistance genes have shown to be omnipresent in the environment. In this study, we investigated the effect of vancomycin (VA) on denitrifying bacteria in river sediments of a Waste Water Treatment Plant, receiving both domestic and hospital waste. We exposed these sediments continuously in flow-through reactors to different VA concentrations under denitrifying conditions (nitrate addition and anoxia) in order to determine potential nitrate reduction rates and changes in sedimentary microbial community structures. The presence of VA had no effect on sedimentary nitrate reduction rates at environmental concentrations, whereas a change in bacterial (16S rDNA) and denitrifying (nosZ) community structures was observed (determined by polymerase chain reaction-denaturing gradient gel electrophoresis). The bacterial and denitrifying community structure within the sediment changed upon VA exposure indicating a selection of a non-susceptible VA population.
显示更多 [+] 显示较少 [-]Exposure to vancomycin causes a shift in the microbial community structure without affecting nitrate reduction rates in river sediments 全文
2015
Laverman, Anniet M. | Cazier, Thibaut | Yan, Chen | Roose-Amsaleg, Céline | Petit, Fabienne | Garnier, Josette | Berthe, Thierry | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Morphodynamique Continentale et Côtière (M2C) ; Université de Caen Normandie (UNICAEN) ; Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN) ; Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)
International audience | Antibiotics and antibiotic resistance genes have shown to be omnipresent in the environment. In this study, we investigated the effect of vancomycin (VA) on denitrifying bacteria in river sediments of a Waste Water Treatment Plant, receiving both domestic and hospital waste. We exposed these sediments continuously in flow-through reactors to different VA concentrations under denitrifying conditions (nitrate addition and anoxia) in order to determine potential nitrate reduction rates and changes in sedimentary microbial community structures. The presence of VA had no effect on sedimentary nitrate reduction rates at environmental concentrations, whereas a change in bacterial (16S rDNA) and denitrifying (nosZ) community structures was observed (determined by polymerase chain reaction-denaturing gradient gel electrophoresis). The bacterial and denitrifying community structure within the sediment changed upon VA exposure indicating a selection of a non-susceptible VA population.
显示更多 [+] 显示较少 [-]Exposure to vancomycin causes a shift in the microbial community structure without affecting nitrate reduction rates in river sediments 全文
2015
Laverman, Anniet M. | Cazier, Thibaut | Yan, Chen | Roose-Amsaleg, Céline | Petit, Fabienne | Garnier, Josette | Berthe, Thierry
Antibiotics and antibiotic resistance genes have shown to be omnipresent in the environment. In this study, we investigated the effect of vancomycin (VA) on denitrifying bacteria in river sediments of a Waste Water Treatment Plant, receiving both domestic and hospital waste. We exposed these sediments continuously in flow-through reactors to different VA concentrations under denitrifying conditions (nitrate addition and anoxia) in order to determine potential nitrate reduction rates and changes in sedimentary microbial community structures. The presence of VA had no effect on sedimentary nitrate reduction rates at environmental concentrations, whereas a change in bacterial (16S rDNA) and denitrifying (nosZ) community structures was observed (determined by polymerase chain reaction–denaturing gradient gel electrophoresis). The bacterial and denitrifying community structure within the sediment changed upon VA exposure indicating a selection of a non-susceptible VA population.
显示更多 [+] 显示较少 [-]Radioactivity in the Kuwait marine environment — Baseline measurements and review 全文
2015
Uddin, S. | Aba, A. | Fowler, S.W. | Behbehani, M. | Ismaeel, A. | Al-Shammari, H. | Alboloushi, A. | Mietelski, J.W. | Al-Ghadban, A. | Al-Ghunaim, A. | Khabbaz, A. | Alboloushi, O.
The Arabian Gulf region is moving towards a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran, and others soon to be constructed in Abu Dhabi and Saudi Arabia. Radiological safety is becoming a prime concern in the region. This study compiles available data and presents recent radionuclide data for the northern Gulf waters, considered as pre-nuclear which will be a valuable dataset for future monitoring work in this region. Radionuclide monitoring in the marine environment is a matter of prime concern for Kuwait, and an assessment of the potential impact of radionuclides requires the establishment and regular updating of baseline levels of artificial and natural radionuclides in various environmental compartments. Here we present baseline measurements for 210Po, 210Pb, 137Cs, 90Sr, and 3H in Kuwait waters. The seawater concentration of 3H, 210Po, 210Pb, 137Cs, and 90Sr vary between 130–146, 0.48–0.68, 0.75–0.89, 1.25–1.38 and 0.57–0.78mBqL−1, respectively. The 40K concentration in seawater varies between 8.9–9.3BqL−1. The concentration of 40K, total 210Pb, 137Cs, 90Sr, 226Ra, 228Ra, 238U, 235U, 234U, 239+240Pu and 238Pu were determined in sediments and range, respectively, between 353–445, 23.6–44.3, 1.0–3.1, 4.8–5.29, 17.3–20.5, 15–16.4, 28.7–31.4, 1.26–1.30, 29.7–30.0, 0.045–0.21 and 0.028–0.03Bqkg−1 dry weight. Since, radionuclides are concentrated in marine biota, a large number of marine biota samples covering several trophic levels, from microalgae to sharks, were analyzed. The whole fish concentration of 40K, 226Ra, 224Ra, 228Ra, 137Cs, 210Po and 90Sr range between 230–447, 0.7–7.3, <0.5–6.6, <0.5–15.80, <0.17, 0.88–4.26 and 1.86–5.34Bqkg−1 dry weight, respectively. 210Po was found to be highly concentrated in several marine organisms with the highest 210Po concentration found in Marica marmorata (193.5–215.6Bqkg−1 dry weight). 210Po in most dissected fish samples shows increasing concentrations in the following order: edible tissue, gills, digestive system, liver and fecal matter. Fish fecal pellets had 210Po concentrations several orders of magnitude higher than the seawater, fish muscle, and the fishes' ingested food. The high 210Po concentration in fish fecal matter, suggest that the bulk of 210Po content in fish was eventually excreted back into the environment as fecal pellets. In most fish high concentrations were noted in liver, with the highest 210Po concentration recorded in shark liver (126.2–141.5Bqkg−1 wet). Moreover, 210Po concentration in the soft tissue of molluscs (10.36–215.60Bqkg−1 dry weight) was far higher than that in fish muscle (0.05–7.49Bqkg−1 wet weight). A seasonal drop in 210Po concentration in seawater was observed to vary with the abundance of phytoplankton and macroalgae due possibly to biological dilution. 137Cs concentration in all the fish sampled was below the detection limit, and the concentration in seawater was also low; hence such low levels provide an opportunity to use this radionuclide as an indicator for any future radiocesium releases in this region.
显示更多 [+] 显示较少 [-]Organophosphorous flame retardants in biota from Svalbard, Norway 全文
2015
Hallanger, Ingeborg G. | Sagerup, Kjetil | Evenset, Anita | Kovacs, Kit M. | Leonards, Pim | Fuglei, Eva | Routti, Heli | Aars, Jon | Strøm, Hallvard | Lydersen, Christian | Gabrielsen, Geir Wing
Eight arctic species, including fish, birds and mammals, from diverse habitats (marine and terrestrial) within the Svalbard Archipelago, Norway, were screened for 14 organophosphorus flame retardant (PFR) compounds. Ten PFRs were detected: tris(2-chloroethyl)phosphate (TCEP), tris(2-chloroisopropyl)phosphate (TCIPP), tris(1,3-dichloro-2-propyl)phosphate (TDCIPP), triphenyl phosphate (TPHP); 2-ethylhexyl diphenyl phosphate (EHDPP); tris(2-butoxyethyl)phosphate (TBOEP); tritolyl phosphate (TCrP); triisobutyl phosphate (TIBP); tris(2-ethylhexyl)phosphate (TEHP); and butyl diphenyl phosphate (DPhBP). The greatest number of different PFR compounds, and the highest detection frequency were measured in capelin (Mallotus villotus), and the lowest in Brünnich's guillemot (Uria lomvia). The highest concentrations of ΣPFR, as well as the highest concentration of a single PFR compound, TBOEP, were measured in arctic fox (Vulpes lagopus). The presence of PFR compounds in arctic biota indicates that these compounds can undergo long-range transport and are, to some degree, persistent and bioaccumulated. The potential for biomagnification from fish to higher trophic levels seems to be limited.
显示更多 [+] 显示较少 [-]Rapid physical and chemical transformation of traffic-related atmospheric particles near a highway 全文
2015
Jeong, Cheol-Heon | Evans, Greg J. | Healy, Robert M. | Jadidian, Parnian | Wentzell, Jeremy | Liggio, John | Brook, Jeffrey R.
The health of a substantial portion of urban populations is potentially being impacted by exposure to traffic–related atmospheric pollutants. To better understand the rapid physical and chemical transformation of these pollutants, the number size distributions of non–volatile traffic–related particles were investigated at different distances from a major highway. Particle volatility measurements were performed upwind and downwind of the highway using a fast mobility particle sizing spectrometer with a thermodenuder on a mobile laboratory. The number concentration of non–denuded ultrafine particles decreased exponentially with distance from the highway, whereas a more gradual gradient was observed for non–volatile particles. The non–volatile number concentration at 27 m was higher than that at 280 m by a factor of approximately 3, and the concentration at 280 m was still higher than that upwind of the highway. The proportion of non–volatile particles increased away from the highway, representing 36% of the total particle number at 27 m, 62% at 280 m, and 81% at the upwind site. A slight decrease in the geometric mean diameter of the non–volatile particle size distributions from approximately 35 nm to 30 nm was found between 27 m and 280 m, in contrast to the growth of non–denuded particles with increasing distance from the highway. Single particle analysis results show that the contribution of elemental carbon (EC)–rich particle types at 27 m was higher than the contribution at 280 m by a factor of approximately 2. The findings suggest that people living or spending time near major roadways could be exposed to elevated number concentrations of nucleation–mode volatile particles (<30 nm), Aitken–mode non–volatile particles (30-100 nm), and EC–rich fine–mode particles (>100 nm). The impact of the highway emissions on air quality was observable up to 300 m.
显示更多 [+] 显示较少 [-]Application of bias adjustment techniques to improve air quality forecasts 全文
2015
Silibello, Camillo | D'Allura, Alessio | Finardi, Sandro | Bolignano, Andrea | Sozzi, Roberto
Two bias adjustment techniques, the hybrid forecast (HF) and the Kalman filter (KF), have been applied to investigate their capability to improve the accuracy of predictions supplied by an air quality forecast system (AQFS). The studied AQFS operationally predicts NO2, ozone, particulate matter and other pollutants concentrations for the Lazio Region (Central Italy). A thorough evaluation of the AQFS and the two techniques has been performed through calculation and analysis of statistical parameters and skill scores. The evaluation performed considering all Lazio region monitoring sites evidenced better results for KF than for HF. RMSE scores were reduced by 43.8% (33.5% HF), 25.2% (13.2% HF) and 41.6% (39.7% HF) respectively for hourly averaged NO2, hourly averaged O3 and daily averaged PM10 concentrations. A further analysis performed clustering the monitoring stations per type showed a good performance of the AQFS for ozone for all the groups of stations (r = 0.7), while satisfactory results were obtained for PM10 and NO2 at rural background (r = 0.6) and Rome background stations (r = 0.7). The skill scores confirmed the capability of the adopted techniques to improve the reproduction of exceedance events.
显示更多 [+] 显示较少 [-]A heavy haze episode in Beijing in February of 2014: Characteristics, origins and implications 全文
2015
Yan, Renchang | Yu, Shaocai | Zhang, Qingyu | Li, Pengfei | Wang, Si | Chen, Bixin | Liu, Weiping
More than half Chinese cities are suffering from severe air pollution due to the rapid development of industry and urbanization. Beijing, as a political and cultural center of China, has frequently suffered from severe haze. However, the precise sources of air pollution in Beijing still remain uncertain. In this study, the observational data (PM2.5, PM10, O3, NO2, CO and SO2) at ten monitoring stations from February 8 to 28, 2014, in Beijing were used to analyze air pollution. The satellite observations for aerosol optical thickness were also used. Backward trajectory model and receptor models were used to identify the sources of air pollution in Beijing. On the basis of PM2.5 concentrations, we separated the whole data into three categories: relatively clean air (PM2.5 concentrations less than 75 μg m–3), haze (PM2.5 concentrations greater than 75 μg m3 but less than 200 μg m3) and heavy haze (PM2.5 concentrations greater than 200 μg m3). The results show that the average concentrations of PM2.5 are 29.5 μg m3, 136.6 μg m3 and 311.2 μg m3 for relatively clean air, haze and heavy haze cases, respectively. The back trajectory cluster analysis reveals that the predominant clusters are east and south for the heavy haze case. The results of the receptor models show that for the haze case, pollutants mainly originated from south of Beijing such as Dezhou, Liaocheng and Heze in Shandong province, while for the heavy haze case, pollutants were mainly from southwest of Beijing such as Baoding, Hengshui and Handan in Hebei province. These results indicate that the emissions in the surrounding provinces made a significant contribution to Beijing's air pollution. Thus, it is necessary to implement air pollution control for all surrounding areas, especially for the industrial zones in the south/southwest regions of Beijing.
显示更多 [+] 显示较少 [-]Trends in indoor–outdoor PM2.5 research: A systematic review of studies conducted during the last decade (2003–2013) 全文
2015
Mohammed, Mohammed O.A. | Song, Wei–Wei | Ma, Wan–Li | Li, Wen–Long | Ambuchi, John J. | Thabit, Mohammed | Li, Yi–Fan
There has been growing concern about potential health risks from exposure to PM2.5 (fine particulate matter). The importance of conducting simultaneous indoor and outdoor measurements emerged because people, especially in developed countries, spend more than 90% of their time indoors. Great spatial and temporal variations in human exposure to PM2.5 have recently been reported. This review aims to identify the main research areas that have attracted recent attention, any possible gaps in the measurements of PM2.5 in various microenvironments, and the relationships between indoor and outdoor concentrations. This study also provides recommendations for further studies on PM2.5 measurement methods and exposure levels. To achieve these goals, this review included articles published online from 2003 to 2013 in the Science Direct and Web of Science databases. In the initial screening stage, 113 abstracts selected while 61 articles were remained for full review. The reviewed studies consistently showed positive correlations between indoor and outdoor PM2.5. Sulfate/sulfur concentrations were used intensively for calculating the infiltration factor (FINF). The higher FINF indicated high infiltration of outdoor PM2.5 into indoor areas. Great percentage (42%) of the reviewed filter–based studies was conducted in Europe, followed by a similar amount (38%) in the USA, and 20% in Asia, indicating a lack in PM2.5 research in other parts of the world. It was difficult to conclude that ambient fixed–site monitoring provided accurate estimations of actual exposure to PM2.5– Studies shown trends of higher personal concentrations compared to indoor and outdoor ones. Higher indoor levels of OC (organic carbon), compared to outdoor levels, were consistently reported. The opposite trend was true for EC (elemental carbon), and there were higher indoor OC/EC ratios than outdoor OC/EC ratios. There was a consistent general trend of a high (r>0.70) correlation between indoor and outdoor EC, while the correlation between indoor and outdoor OC was much weaker (r=022–0.75). The higher indoor OC/EC ratios, compared to the outdoor OC/EC ratios, reflects multiple sources of indoor OC. Sulfate (SO42–), nitrate (NO3–), and ammonium (NH4+) were primary contributors to PM2.5 mass.
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