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Metal concentrations in sediments from tourist beaches of Miri City, Sarawak, Malaysia (Borneo Island) Полный текст
2013
Nagarajan, R. | Jonathan, M.P. | Roy, Priyadarsi D. | Wai-Hwa, L. | Prasanna, M.V. | Sarkar, S.K. | Navarrete-López, M.
Forty-three sediment samples were collected from the beaches of Miri City, Sarawak, Malaysia to identify the enrichment of partially leached trace metals (PLTMs) from six different tourist beaches. The samples were analyzed for PLTMs Fe, Mn, Cr, Co, Cu, Ni, Pb, Sr and Zn. The concentration pattern suggest that the southern side of the study area is enriched with Fe (1821–6097μgg−1), Mn (11.57–90.22μgg−1), Cr (51.50–311μgg−1), Ni (18–51μgg−1), Pb (8.81–84.05μgg−1), Sr (25.95–140.49μgg−1) and Zn (12.46–35.04μgg−1). Compared to the eco-toxicological values, Cr>Effects range low (ERL), Lowest effect level (LEL), Severe effect level (SEL); Cu>Unpolluted sediments, ERL, LEL; Pb>Unpolluted sediments and Ni>ERL and LEL. Comparative results with other regions indicate that Co, Cr, Cu, Ni and Zn are higher, indicating an external input rather than natural process.
Показать больше [+] Меньше [-]Kinetics and equilibrium models for the sorption of tributyltin to nZnO, activated carbon and nZnO/activated carbon composite in artificial seawater Полный текст
2013
Ayanda, Olushola S. | Fatoki, Olalekan S. | Adekola, Folahan A. | Ximba, Bhekumusa J.
The removal of tributyltin (TBT) from artificial seawater using nZnO, activated carbon and nZnO/activated carbon composite was systematically studied. The equilibrium and kinetics of adsorption were investigated in a batch adsorption system. Equilibrium adsorption data were analyzed using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) isotherm models. Pseudo first- and second-order, Elovich, fractional power and intraparticle diffusion models were applied to test the kinetic data. Thermodynamic parameters such as ΔG°, ΔS° and ΔH° were also calculated to understand the mechanisms of adsorption. Optimal conditions for the adsorption of TBT from artificial seawater were then applied to TBT removal from natural seawater. A higher removal efficiency of TBT (>99%) was obtained for the nZnO/activated carbon composite material and for activated carbon but not for nZnO.
Показать больше [+] Меньше [-]Spatial variations in polycyclic aromatic hydrocarbons concentrations at surface sediments from the Cyprus (Eastern Mediterranean): Relation to ecological risk assessment Полный текст
2013
Darılmaz, Enis | Kontaş, Aynur | Uluturhan, Esin | Akçalı, İdil | Altay, Oya
The objective of the present study was to evaluate the distribution, sources, origins, and environmental risk assessment of polycyclic aromatic hydrocarbons (16 US EPA priority pollutants) pollution in 23 surface sediments from Cyprus coast. The mean total polycyclic aromatic hydrocarbons (PAHs) concentrations in the sediments from Gemi Konagi, Girne and Gazi Magusa areas were found 47, 52 and 50ng/g, respectively. Molecular ratios and principle component analysis indicated that PAH pollution originated mainly from fossil sources, with higher pyrolytic contributions. The 2–3 ring PAHs were dominant in Cyprus sediments. Concentrations of PAHs observed in this study were compared with available soil quality guidelines and the concentrations were lower than the guideline values. The guideline values suggested that the Cyprus sediments were likely to be not contaminated by toxic PAH compounds.
Показать больше [+] Меньше [-]Trophic calculations reveal the mechanism of population-level variation in mercury concentrations between marine ecosystems: Case studies of two polar seabirds Полный текст
2013
Brasso, Rebecka L. | Polito, Michael J.
The incorporation of quantitative trophic level analysis in ecotoxicological studies provides explanatory power to identify the factors, trophic or environmental, driving population-level variation in mercury exposure at large geographic scales. In the Antarctic marine ecosystem, mercury concentrations and stable isotope values in Adélie penguins (Pygoscelis adeliae) were compared between the Antarctic Peninsula and the Ross Sea. Correcting tissue δ15N values for baseline δ15N values revealed population-level differences in trophic position which contributes to differences in mercury. Data from Thick-billed murres (Uria lomvia) were synthesized from published values from Baffin Bay and Svalbard to demonstrate the utility of baseline δ15N values in identifying differences in environmental mercury exposure independent of diet. Here, we demonstrate the importance of calculating population-specific trophic level data to uncover the source of variation in mercury concentrations between geographically distinct populations of marine predators.
Показать больше [+] Меньше [-]Effects of ocean acidification on the embryos and larvae of red king crab, Paralithodes camtschaticus Полный текст
2013
Christopher Long, W. | Swiney, Katherine M. | Foy, Robert J.
The effects of the decline in ocean pH, known as ocean acidification, on marine species are not well understood. To test the effects on embryos and larvae of red king crab, Paralithodes camtschaticus, ovigerous crab and their larvae were held in CO2-acidified (pH 7.7) and control (ambient; pH 8.0) seawater during development. Morphometrics, hatch duration, fecundity, survival, mineral content, and condition were measured. Acidified embryos had 4% larger eyes and 5% smaller yolks, while mean hatch duration was 33% longer and female fecundity was unaffected. Acidified embryos also resulted in 4% longer larvae while acidified larvae had lower survival. Calcium content of both larvae and female carapaces after molting increased by 5% and 19%, respectively. Although ocean acidification may increase larval size and calcium content, the implications of this are unclear and decreased survival is likely to harm red king crab populations.
Показать больше [+] Меньше [-]Modeling air concentrations and risk of carcinogens and co–carcinogens in Gibraltar and source apportionment of nearby industrial facilities Полный текст
2013
Fauser, Patrik | Sanderson, Hans | Lofstrom, Per
Airborne exposures of carcinogenic and co–carcinogenic pollutants, emitted from industries and various diffuse sources in a 10km radius of Gibraltar, were calculated at the west side of the Rock of Gibraltar facing the Bay. 2005 and 2008 industrial annual emission rates reported to E–PRTR and 2005 municipal diffuse annual emission rates were entered in OML–Multi, a multi–source version of an atmospheric Gaussian plume local scale dispersion model. The model results reveal that carcinogens PAH, represented by benzo[a]pyrene (BaP), arsenic and nickel, and potentially chromium are the priority pollutants with respect to human cancer risk and that the contribution from industrial sources on the Spanish coastal area exceeds that from the diffuse sources from adjacent Spanish municipalities. There is a decrease in annual mean air concentrations from industrial emissions between the years 2005 and 2008. The assessment of contribution to the Gibraltar air concentrations of the priority pollutants from industrial sources shows that refinery CEPSA, chemical industry Petresa and petroleum industry Lubricantes del Sur are significant for nickel. Chemical industry Interquisa is significant for PAHs with a notable decrease in PAH emissions from 2006 to 2007, whereas the contribution from CEPSA is more constant. For arsenic only CEPSA shows a continuous trend and contributes to the 2008 air concentration together with sewerage Edar de la Linea de la Concepcion. CEPSA and metal industry Acerinox contribute the most to the chromium air concentrations. NO2/NOx is the most critical co–carcinogen and electricity plant Central Termica Los Barrios, CEPSA, electricity plant Generacion Electrica Peninsular and electricity plant Cogeneracion de Interquisa are the most significant contributors to the air concentrations in Gibraltar. Pollutant contributions from CEPSA flaring, ship traffic in the Bay and Strait, local road traffic and local diesel generators are currently un–quantified.
Показать больше [+] Меньше [-]Characteristics of visibility and particulate matter (PM) in an urban area of Northeast China Полный текст
2013
Zhao, Hujia | Che, Huizheng | Zhang, Xiaoye | Ma, Yanjun | Wang, Yangfeng | Wang, Hong | Wang, Yaqiang
The visibility data from 2010 to 2012 were obtained at Shenyang in Northeast China and the relations between visibility, PM mass concentration and meteorological variables were statistically analyzed. These results demonstrate that the monthly–averaged visibility over Shenyang was higher in March and September with values of approximately 19.0±4.3 km and 17.1±4.3 km, respectively. Low visibility over Shenyang occurred in January at approximately 11.0±4.7 km. Among the meteorological variables considered, wind speed was the main meteorological factor that influenced visibility and PM mass concentrations. The relation between visibility and PM indicates that fine particles are already a main source of pollutants, the existence of which is the most important factor in the deterioration of visibility in an urban area of Northeast China. The study also shows an obvious diurnal variation and weekend effects of visibility and PM, which are mainly caused by human activities. Results of this study highlight the significant impact of fine particles on air pollution and visibility in an urban area of Northeast China.
Показать больше [+] Меньше [-]Risk assessment for exemptions from ballast water management – The Baltic Sea case study Полный текст
2013
David, Matej | Gollasch, Stephan | Leppäkoski, Erkki
The International Convention for the Control and Management of Ship’s Ballast Water and Sediments sets requirements to prevent organism transfers. Vessels on certain routes can be exempted from such requirements based on risk assessment (RA). As the convention nears its entry into force, the interest in exemptions increases. Such RA should be conducted according to the International Maritime Organization G7 Guidelines. We present a RA study for exemptions applied to intra-Baltic shipping considering different RA methods, i.e., environmental matching, species specific method including target species and species biogeographical aspects. As reliable species data in the ports considered are unavailable and following the precautionary principle, no exemptions should be granted. To ensure data reliability, port baseline surveys and regular monitoring programs should be undertaken during the exemption period as new species found influence the RA result. The RA model prepared is considered as of value to other areas worldwide.
Показать больше [+] Меньше [-]Microbiological composition of native and exotic clams from Tagus estuary: Effect of season and environmental parameters Полный текст
2013
Anacleto, Patrícia | Pedro, Sónia | Nunes, Maria Leonor | Rosa, Rui | Marques, António
The influence of seasonal and environmental parameters on the occurrence of bacteria was investigated in two clam species (Venerupis pullastra and Ruditapes philippinarum), water and sediment from the Tagus estuary. Total viable counts (TVC), Escherichia coli, Salmonella spp. and Vibrio spp. were evaluated during one-year. Overall, significant seasonal variations were found in both sampling sites, especially for E. coli and Vibrio spp. levels. In summer, significantly higher Vibrio spp. levels were found in R. philippinarum and sediment samples, but not in V. pullastra clams and water samples. In contrast, significantly higher TVC and E. coli levels were observed in winter months in water and sediment samples. Salmonella spp. was generally isolated when higher levels of E. coli were detected, particularly in R. philippinarum. This study is useful for authorities to develop monitoring strategies for coastal contamination and to estimate human health risks associated with the consumption of bivalves.
Показать больше [+] Меньше [-]Plastic debris in Mediterranean seabirds Полный текст
2013
Codina-García, Marina | Militão, Teresa | Moreno Lázaro, Javier | González-Solís, Jacob
Plastic debris is often ingested by marine predators and can cause health disorders and even death. We present the first assessment of plastic ingestion in Mediterranean seabirds. We quantified and measured plastics accumulated in the stomach of 171 birds from 9 species accidentally caught by longliners in the western Mediterranean from 2003 to 2010. Cory’s shearwaters (Calonectris diomedea) showed the highest occurrence (94%) and large numbers of small plastic particles per affected bird (on average N=15.3±24.4 plastics and mass=23.4±49.6mg), followed by Yelkouan shearwaters (Puffinus yelkouan, 70%, N=7.0±7.9, 42.1±100.0mg), Balearic shearwaters (Puffinus mauretanicus, 70%, N=3.6±2.9, 5.5±9.7mg) and the rest of species (below 33%, N=2.7, 113.6±128.4mg). Plastic characteristics did not differ between sexes and were not related to the physical condition of the birds. Our results point out the three endemic and threatened shearwater species as being particularly exposed to plastic accumulation.
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