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Elemental composition of two ecologically contrasting seamount fishes, the bluemouth (Helicolenus dactylopterus) and blackspot seabream (Pagellus bogaraveo) 全文
2015
Raimundo, Joana | Vale, Carlos | Martins, Inês | Fontes, Jorge | Graça, Gonçalo | Caetano, Miguel
Concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb were determined in muscle, liver and gonads of two ecologically contrasting fishes, Helicolenus dactylopterus (benthic) and Pagellus bogaraveo (benthopelagic). Elevated concentrations of As, Se and Cd found in tissues of both species appear to mirror the contribution of volcanic activity to the natural inputs of elements to Azorean waters. Results showed different element accumulation between the two species. Whereas higher concentrations were found in the liver of P. bogaraveo, elevated values were observed in the muscle of H. dactylopterus. Differences in accumulation are most likely related to metabolic rates, diet specificities and habitat. Concentrations in gonads varied up to four orders of magnitude, being higher and more variable in P. bogaraveo than H. dactylopterus. Elevated values of Cd were detected in gonads of both species despite its non-essential role on metabolic functions, presumably related to elimination.
显示更多 [+] 显示较少 [-]Wildfires impact on surface nitrogen oxides and ozone in Central Italy 全文
2015
Di Carlo, Piero | Aruffo, Eleonora | Biancofiore, Fabio | Busilacchio, Marcella | Pitari, Giovanni | Dari-Salisburgo, Cesare | Tuccella, Paolo | Kajii, Yoshizumi
A summer campaign in Central Italy was carried out to study the impact of fire emissions on the mixing ratios of surface trace gases. Observations with a selective and sensitive instrument that uses the laser induced fluorescence technique for direct measurements of nitrogen dioxide (NO2), show a significant increase of NO2 mixing ratios, in the evening, when a fire plume reached the observations site. The increase of NO2 mixing ratios is well correlated (R=0.83) with that of particulate matter (PM), which is one of the primary product of forest and grassland fires. The tight correlation between NO2 and PM is used to improve the performance of a statistical regression model to simulate the observed O3, and to highlight the effect of fire emissions on the O3 mixing ratios. The statistical regression model of O3 improves in terms of performance (bias reduction of 77% and agreement enhancement of 10% for slope and correlation coefficient) when PM2.5 is included as additional input and proxy of the fire emissions among the usual input parameters (meteorological data and NO2 mixing ratios). A case study, comparing observed and modeled O3 in different days (with and without fire plume), suggests an impact of fire emissions on the O3 mixing ratios of about 10%.
显示更多 [+] 显示较少 [-]Effects of sediments on the reproductive cycle of corals 全文
2015
Jones, R. | Ricardo, G.F. | Negri, A.P.
Dredging, river plumes and natural resuspension events can release sediments into the water column where they exert a range of effects on underlying communities. In this review we examine possible cause–effect pathways whereby light reduction, elevated suspended sediments and sediment deposition could affect the reproductive cycle and early life histories of corals. The majority of reported or likely effects (30+) were negative, including a suite of previously unrecognized effects on gametes. The length of each phase of the life-cycle was also examined together with analysis of water quality conditions that can occur during a dredging project over equivalent durations, providing a range of environmentally relevant exposure scenarios for future testing. The review emphasizes the need to: (a) accurately quantify exposure conditions, (b) identify the mechanism of any effects in future studies, and (c) recognize the close interlinking of proximate factors which could confound interpretation of studies.
显示更多 [+] 显示较少 [-]Persistent organic pollutants carried on plastic resin pellets from two beaches in China 全文
2015
Zhang, Weiwei | Ma, Xindong | Zhang, Zhifeng | Wang, Yan | Wang, Juying | Wang, Jing | Ma, Deyi
Microplastics provide a mechanism for the long-range transport of hydrophobic chemical contaminants to remote coastal and marine locations. In this study, plastic resin pellets were collected from Zhengmingsi Beach and Dongshan Beach in China. The collected pellets were analyzed for PAHs, PCBs, HCHs, DDTs, chlordane, heptachlor, endosulfan, aldrin, dieldrin and endrin. The total concentration of PCBs ranged from 34.7–213.7ngg−1 and from 21.5–323.2ngg−1 in plastic resin pellets for Zhengmingsi Beach and Dongshan Beach respectively. The highest concentrations of PCBs were observed for congeners 44, 110, 138, 155 and 200. The total concentration of PAHs ranged from 136.3–1586.9ngg−1 and from 397.6–2384.2ngg−1 in the plastic pellets, whereas DDTs concentration ranged from 1.2–101.5ngg−1 and from 1.5–127.0ngg−1 for the two beaches. The elevated concentrations of pollutants appear to be related to extensive industrial development, agricultural activity and the use of coal in the area.
显示更多 [+] 显示较少 [-]Heavy metals in red crabs, Chaceon quinquedens, from the Gulf of Mexico 全文
2015
Perry, Harriet | Isphording, Wayne | Trigg, Christine | Riedel, Ralf
The red crab, Chaceon quinquedens, is distributed in deep waters of the Gulf of Mexico (GOM) and is most abundant in an area associated with sediment deposition from the Mississippi River. Sediment geochemistry and biological and ecological traits of red crabs favor accumulation of contaminants. Red crabs, sediment, and bottom water samples were taken from three distinct geographic locations representing areas with differing exposure to contaminant laden effluents from the Mississippi River. Inductively coupled plasma spectrophotometry and atomic absorption spectrophotometry were employed to determine levels of heavy metals in red crab muscle tissue. Ion site partitioning was used to determine metal speciation in sediments. Red crabs showed evidence of heavy metal bioaccumulation in all sample areas with high variability in contaminant levels in individual crabs for some metals. Bioavailability of metals in sediment did not always result in accumulation in muscle tissue.
显示更多 [+] 显示较少 [-]Three decades of sea water abstraction by Kapar power plant (Malaysia): What impacts on tropical zooplankton community? 全文
2015
Chew, L.L. | Chong, V.C. | Wong, R.C.S. | Lehette, P. | Ng, C.C. | Loh, K.H.
Zooplankton samples collected before (1985–86) and after (2013–14) the establishment of Kapar power station (KPS) were examined to test the hypothesis that increased sea surface temperature (SST) and other water quality changes have altered the zooplankton community structure. Elevated SST and reduced pH were detected between before and after impact pairs, with the greatest impact at the station closest to KPS. Present PAHs and heavy metal concentrations are unlikely causal factors. Water parameter changes did not affect diversity but community structure of the zooplankton. Tolerant small crustaceans, salps and larvaceans likely benefited from elevated temperature, reduced pH and shift to a more significant microbial loop exacerbated by eutrophication, while large crustaceans were more vulnerable to such changes. It is predicted that any further rise in SST will remove more large-bodied crustacean zooplankton, the preferred food for fish larvae and other meroplankton, with grave consequences to fishery production.
显示更多 [+] 显示较少 [-]Forensic investigation of aliphatic hydrocarbons in the sediments from selected mangrove ecosystems in the west coast of Peninsular Malaysia 全文
2015
Vaezzadeh, Vahab | Zakaria, Mohamad Pauzi | Shau-Hwai, Aileen Tan | Ibrahim, Zelina Zaiton | Mustafa, Shuhaimi | Abootalebi-Jahromi, Fatemeh | Masood, Najat | Magam, Sami Mohsen | Alkhadher, Sadeq Abdullah Abdo
Peninsular Malaysia has gone through fast development during recent decades resulting in the release of large amounts of petroleum and its products into the environment. Aliphatic hydrocarbons are one of the major components of petroleum. Surface sediment samples were collected from five rivers along the west coast of Peninsular Malaysia and analyzed for aliphatic hydrocarbons. The total concentrations of C10 to C36 n-alkanes ranged from 27,945 to 254,463ng·g−1dry weight (dw). Evaluation of various n-alkane indices such as carbon preference index (CPI; 0.35 to 3.10) and average chain length (ACL; 26.74 to 29.23) of C25 to C33 n-alkanes indicated a predominance of petrogenic source n-alkanes in the lower parts of the Rivers, while biogenic origin n-alkanes from vascular plants are more predominant in the upper parts, especially in less polluted areas. Petrogenic sources of n-alkanes are predominantly heavy and degraded oil versus fresh oil inputs.
显示更多 [+] 显示较少 [-]Glyphosate and AMPA in the estuaries of the Baltic Sea method optimization and field study 全文
2015
Skeff, Wael | Neumann, Christine | Schulz-Bull, Detlef E.
Water samples from ten German Baltic estuaries were collected in 2012 in order to study the presence of the herbicide glyphosate, its primary metabolite AMPA and their potential transport to the marine environment. For the analyses an LC–MS/MS based analytical method after derivatization with FMOC-Cl was optimized and validated for marine water samples. All investigated estuarine stations were contaminated with AMPA and nine of them also with glyphosate. Concentration ranges observed were 28 to 1690ng/L and 45 to 4156ng/L for glyphosate and AMPA, respectively with strong spatial and temporal fluctuations. Both contaminants were found at inbound sampling sites in the stream Muehlenfliess and concentrations decreased along the salinity gradient to the estuaries of the Baltic Sea. The data obtained in this study clearly depict the transport of glyphosate and AMPA to the Baltic Sea. Hence, detailed fate and risk assessment for both contaminants in marine environments are required.
显示更多 [+] 显示较少 [-]Distribution and enrichment of trace metals in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana in the Gulf of Guinea 全文
2015
Mahu, Edem | Nyarko, Elvis | Hulme, Samuel | Coale, Kenneth H.
We present results of a preliminary geochemical assessment of Cd, Pb, V, As, Ni, Cu, Zn, Mg, Al, K, Ca, and Fe in marine sediments from the Eastern Equatorial Atlantic, off the Coast of Ghana. Samples were taken along 4 regions G1, G2, G3 and G4 at approximately 25m, 100m, and 250m, 500m and 1000m depths. Elemental compositions were assessed through the estimation of Al-normalized enrichment factors and geochemical accumulation indices, and the concentrations determined to produce any potential toxic effects to biota. Significant enrichment of the bottom sediments with Cd, Ni and As were observed at some locations with sediments showing signs of heavy pollution with As at region G4. Apart from Ni, V and As which were beyond threshold effects levels at most regions, all other metals were below probable effect levels. Both natural and anthropogenic processes controlled trace metal accumulation and distribution in the Ghanaian coastal environment.
显示更多 [+] 显示较少 [-]Air Quality in a Cleaner Energy World 全文
2015
Wuebbles, Donald J. | Sanyal, Swarnali
Two major environmental issues, air quality and climate change, are interlinked because of their large dependence on atmospheric emissions from human activities, especially from the burning of fossil fuels. Emission of air pollutants and heat trapping gases have greatly increased over the last five decades from our dependence throughout the world on conventional fossil fuel sources in production of electricity and in transportation systems, resulting in significant environmental issues with air quality and climate change throughout our planet. Future emissions of pollutants will depend on the choices made about our use of energy and transportation. The purpose of this study is to examine for now and into the future the relationship between energy production, the associated use of fossil fuels, and resulting effects on air pollution. In the process, we examine a clean energy future, imagined in this case for 2050, and then consider the resulting potential effects on air quality.
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