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Assessment of polycyclic aromatic hydrocarbons (PAHs) in mussels (Mytilus galloprovincialis) of Prince Islands, Marmara Sea 全文
2016
Balcıoğlu, Esra Billur
In this study, PAH analyses have been conducted on indigenous mussels. Mussel samples (Mytilus galloprovincialis) have been collected from seven stations of Prince Islands during September 2015. Concentrations of total determined PAHs (sum of 16 compounds) ranged between 664 and 9083ngg−1. The origin of PAHs has been found to be pyrolytic according to the PHE/ANT and FA/PYR ratios in Büyükada. For other islands, PAH origins have been observed as pyrolytic and petrogenic together according to the PHE/ANT, FA/PYR and BaA/CHR ratios.
显示更多 [+] 显示较少 [-]Pressure on oxygen levels of Jakarta Bay 全文
2016
Ladwig, Norbert | Hesse, Karl-J. | van der Wulp, Simon A. | Damar, Ario | Koch, Daniela
Jakarta Bay is subject to inputs of large amounts of dissolved inorganic nutrients and organic matter deriving from the Jakarta Metropolitan Area and its hinterland. As a consequence, inorganic and organic nutrient concentrations in the nearshore area are considerably increased. The hydrographic pattern inside the bay fosters phytoplankton bloom formation due to pronounced vertical density gradients. High Biomass Blooms (HBB) of phytoplankton are observed recurrently, representing an additional source for oxygen consuming degradable organic matter. An oxygen deficiency area of 20km2 can be identified in the eastern part of Jakarta Bay where oxygen levels decrease to 60% saturation, equaling a noxiously low concentration of 4.0mg·dm−3 O2. The absolute minimum detected was 51% O2 or 3.2mg·dm−3 O2. The observed oxygen concentrations fail Indonesian quality standards for seawater.
显示更多 [+] 显示较少 [-]Validating the use of biopsy sampling in contamination assessment studies of small cetaceans 全文
2016
Méndez-Fernandez, Paula | Galluzzi Polesi, Paola | Taniguchi, Satie | de O. Santos, Marcos C. | Montone, Rosalinda C.
Remote biopsy sampling is the most common technique for acquiring samples from free-ranging marine mammals. However, such techniques may result in variable sampling being sometimes superficial skin and blubber biopsies. For decades, blubber has been used to monitor the exposure of marine mammals to persistent organic pollutants (POPs), but little is known regarding the variability of POPs as a function of blubber depth in small cetaceans and the available literature offers variable results. Thus, the aim of the present study was to validate biopsy sampling for monitoring contaminant concentrations in small, free-ranging cetaceans. Samples from the dorsal blubber of 10 incidentally captured Atlantic spotted dolphins (Stenella frontalis) were separated into two different layers (outer and inner) to investigate the influence of sampling depth on POP concentrations. POP concentrations were compared to those of the full blubber layer. The results revealed no significant differences in lipid content between males and females or among the inner, outer and full blubber layers (p>0.05). Moreover, the wet and lipid weight concentrations of all POP classes analysed [i.e. polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), chlordanes (CHLs) and mirex] did not differ significantly with blubber depth (p>0.05). POP classes followed the same decreasing order of wet weight concentrations in blubber layers and full blubber: PCBs>DDTs>PBDEs>mirex>HCB>HCHs>CHLs. Moreover, there was a low degree of differentiation in the accumulation of POP congeners. The present findings indicated that the distribution of contaminants was homogenous with blubber depth, which validates the use of biopsy sampling for the assessment of contaminants in small cetaceans.
显示更多 [+] 显示较少 [-]Numerical evaluation of the use of granulated coal ash to reduce an oxygen-deficient water mass 全文
2016
Yamamoto, Hironori | Yamamoto, Tamiji | Mito, Yugo | Asaoka, Satoshi
Granulated coal ash (GCA), which is a by-product of coal thermal electric power stations, effectively decreases phosphate and hydrogen sulfide (H2S) concentrations in the pore water of coastal marine sediments. In this study, we developed a pelagic–benthic coupled ecosystem model to evaluate the effectiveness of GCA for diminishing the oxygen-deficient water mass formed in coastal bottom water of Hiroshima Bay in Japan. Numerical experiments revealed the application of GCA was effective for reducing the oxygen-deficient water masses, showing alleviation of the DO depletion in summer increased by 0.4–3mgl−1. The effect of H2S adsorption onto the GCA lasted for 5.25years in the case in which GCA was mixed with the sediment in a volume ratio of 1:1. The application of this new GCA-based environmental restoration technique could also make a substantial contribution to form a recycling-oriented society.
显示更多 [+] 显示较少 [-]Characteristics and source apportionment of VOCs in the suburban area of Beijing, China 全文
2016
Wang, Gang | Cheng, Shuiyuan | Wei, Wei | Zhou, Ying | Yao, Sen | Zhang, Hanyu
The measurement of volatile organic compounds (VOCs) was conducted during November 2014 in the suburban area of Beijing, China, covering the period of the Asia-Pacific Economic Cooperation (APEC) meeting period. The VOCs characteristics and source apportionment were analyzed. The average mass concentrations of VOCs were 27.6 ± 19.7 μg/m3 during the sampling period, and aromatics and alkanes were the most abundant VOCs species in atmospheric environment in Beijing which were 12.2 ± 10.3 μg/m3 and 11.3 ± 7.5 μg/m3, respectively. The hourly variation of VOCs was found, with the highest concentration occurring at 8:00 to 9:30 and lowest at 12:30 to 14:00. The sampling period was divided into two periods: period Ⅰ represent the period without emission-reduction measures, and period Ⅱ represent the period with reduction measures. The VOCs concentrations during the period Ⅱ was 31.0% lower than period Ⅰ. The Maximum Incremental Reactivity (MIR) method was applied to analysis the ozone formation potential (OFP). The OFP of VOCs from period Ⅰ was 1.6 times higher than period Ⅱ, and the majority of VOCs species were alkenes and aromatics. Positive matrix factorization was applied to estimate contributions of potential VOCs sources. The vehicle exhaust emission was the major source of VOCs during the two periods, and the contribution to VOCs was 5.7% lower during period Ⅱ than period Ⅰ due to the emission-reduction of vehicle operation.
显示更多 [+] 显示较少 [-]Microplastics in personal care products: Exploring perceptions of environmentalists, beauticians and students 全文
2016
Anderson, A.G. | Grose, J. | Pahl, S. | Thompson, R.C. | Wyles, K.J.
Microplastics enter the environment as a result of larger plastic items breaking down (‘secondary’) and from particles originally manufactured at that size (‘primary’). Personal care products are an important contributor of secondary microplastics (typically referred to as ‘microbeads’), for example in toothpaste, facial scrubs and soaps. Consumers play an important role in influencing the demand for these products and therefore any associated environmental consequences. Hence we need to understand public perceptions in order to help reduce emissions of microplastics. This study explored awareness of plastic microbeads in personal care products in three groups: environmental activists, trainee beauticians and university students in South West England. Focus groups were run, where participants were shown the quantity of microbeads found in individual high-street personal care products. Qualitative analysis showed that while the environmentalists were originally aware of the issue, it lacked visibility and immediacy for the beauticians and students. Yet when shown the amount of plastic in a range of familiar everyday personal care products, all participants expressed considerable surprise and concern at the quantities and potential impact. Regardless of any perceived level of harm in the environment, the consensus was that their use was unnatural and unnecessary. This research could inform future communications with the public and industry as well as policy initiatives to phase out the use of microbeads.
显示更多 [+] 显示较少 [-]Natural mitigation factor adjustment for re-suspended particulate matter emissions inventory for Bogotá, Colombia 全文
2016
Pérez, María Paula | Henderson, Barron H. | Nedbor-Gross, Robert | Pachón, Jorge E.
This work improves atmospheric emissions of particulate matter in Bogotá Colombia, and provides a tool applying this technique around the world. Bogotá's air pollution is largely impacted by particulate matter, and specifically by re-suspended particulate matter (RPM). RPM sources include paved and unpaved roads, agricultural tilling, construction activities, mining and quarrying. RPM emissions are frequently estimated using annual emission factors, time-varying vehicle traffic activity, a time/space invariant meteorological scaling factor, and a time/space invariant correction factor. This work updates the meteorological factors to be hour-specific, and replacing the correction factor with land use-specific local deposition factors. These techniques are codified in a flexible Python tool based on EPA's AP42 methods and the broader emission literature.Meteorology inhibits RPM emission directly via precipitation scavenging and indirectly by accumulation of road surface moisture. The effects of precipitation and surface moisture are parameterized as mitigation factors differently for paved and unpaved roads due to their porosity and drainage characteristics.These estimates of hourly mitigation factors (on average for paved roads: 0.86 and for unpaved roads: 0.61) agree well with annual factors previously used (paved: 0.90; unpaved: 0.60), however hourly factors have clear diurnal patterns that reduce emissions more significantly latter in the day for paved roads (00–12: 0.95; 12–24: 0.78), and to a lesser extent for unpaved roads (00–12: 0.64; 12–24: 0.58).Emissions are also significantly reduced by vehicle induced turbulence and local deposition. The transportable fraction (0.59 ± 0.22), parameterized based on land use, significantly reduced emissions and correlates with unpaved roads (r = 0.30) more so than with paved roads (r = 0.02). These fractions were used to construct a new inventory, which might improve air pollution predictions compared to the raw inventory, as well as new efforts to simulate exposure fields in Bogotá and our understanding of local particulate sources and sinks.
显示更多 [+] 显示较少 [-]Research on carbon emissions embodied in trade between China and South Korea 全文
2016
Yang, Yu | Fei-fan, Chen
With the signature of the free trade agreement, trade ties will develop rapidly between China and South Korea. Based on input–output model, this paper calculates and decomposes the embodied carbon emissions in the trade between China and South Korea from 2000 to 2010, analyses the reasons and gives some future advices. This paper suggests that the embodied carbon emissions surplus is not caused by trade surplus. It further points out that textile and leather industries, chemical manufacturing industries and metal manufacturing industries are three main sectors contributing to imported and exported embodied carbon emissions. In addition, the trade diversion between China and South Korea helps a lot in reducing the global carbon emissions and eases the pressure of carbon emissions in China. This paper also proposes that China should learn advanced technologies from South Korea and reduce carbon-intensive energy consumption in the future.
显示更多 [+] 显示较少 [-]The invasive lionfish, Pterois volitans, used as a sentinel species to assess the organochlorine pollution by chlordecone in Guadeloupe (Lesser Antilles) 全文
2016
Charlotte, Dromard R. | Yolande, Bouchon-Navaro | Cordonnier, Sebastien | Claude, Bouchon
In Guadeloupe, many marine organisms are affected by an organochlorine pollution used in the past by the banana industry to fight against the banana weevil. In the present study, we evaluated the level of contamination of the invasive Indo-Pacific lionfish, Pterois volitans, all around the island. Concentrations of chlordecone varied from 3 to 144μg.kg−1 wet weight. The highest concentrations were recorded when samples were captured in the marine zones located downstream of the previous banana plantations. This contamination seemed to decrease rapidly with the distance from the coast. Mean concentration of chlordecone in Pterois volitans was higher than that of five other fish species collected in similar sites. Due to its position at the top of the trophic web, lionfish was affected by bioaccumulation of chlordecone and can be used as a sentinel species to assess and control the level of contamination of the marine environment by chlordecone.
显示更多 [+] 显示较少 [-]Lead, cadmium and mercury in the blood of the blue-footed booby (Sula nebouxii) from the coast of Sinaloa, Gulf of California, Mexico 全文
2016
Lerma, Miriam | Castillo-Guerrero, José Alfredo | Ruelas-Inzunza, Jorge | Fernández, Guillermo
We used blood samples of the Blue-footed Booby, considering sex (female and male) and age-class (adult and chick) of individuals at different breeding stages during two breeding seasons (2010–2011 and 2011–2012) in Isla El Rancho, Sinaloa, to determine lead, cadmium, and mercury concentrations. Lead and cadmium concentrations were below our detection limit (0.05 and 0.36ppm, respectively). A higher concentration of mercury was found in early stages of breeding, likely related to changes in mercury environmental availability. Mercury concentrations in adults did not relate with their breeding output. Males and adults had higher mercury concentration than females and chicks. We provide information of temporal, sex and age-related variations in the concentrations of mercury in blood of the Blue-footed Booby.
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