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Total petroleum hydrocarbon degradation by hybrid electrobiochemical reactor in oilfield produced water Full text
2016
Mousa, Ibrahim E.
The crude oil drilling and extraction operations are aimed to maximize the production may be counterbalanced by the huge production of contaminated produced water (PW). PW is conventionally treated through different physical, chemical, and biological technologies. The efficiency of suggested hybrid electrobiochemical (EBC) methods for the simultaneous removal of total petroleum hydrocarbon (TPH) and sulfate from PW generated by petroleum industry is studied. Also, the factors that affect the stability of PW quality are investigated. The results indicated that the effect of biological treatment is very important to keep control of the electrochemical by-products and more TPH removal in the EBC system. The maximum TPH and sulfate removal efficiency was achieved 75% and 25.3%, respectively when the detention time was about 5.1min and the energy consumption was 32.6mA/cm2. However, a slight increasing in total bacterial count was observed when the EBC compact unit worked at a flow rate of average 20L/h. Pseudo steady state was achieved after 30min of current application in the solution. Also, the results of the study indicate that when the current intensity was increased above optimum level, no significant results occurred due to the release of gases.
Show more [+] Less [-]Changes in whistle structure of resident bottlenose dolphins in relation to underwater noise and boat traffic Full text
2016
Rako Gospić, Nikolina | Picciulin, Marta
The habitat of the resident bottlenose dolphins (Tursiops truncatus) of the Cres-Lošinj archipelago overlaps with routes of intense boat traffic. Within these waters, Sea Ambient Noise (SAN) was sampled across ten acoustic stations between 2007 and 2009. Data on boat presence was concurrently collected and when dolphins were sighted group behaviour was also recorded.Acoustic recordings were analysed for 1/3 octave bands. Samples containing dolphin whistles were analysed and compared with boat presence and SAN levels. Results indicate that dolphins whistle at higher frequencies in conditions of elevated low frequency noise. Conversely, they reduce maximum, delta and start frequencies and frequency modulations when noise levels increase significantly across higher frequencies. The study shows that high levels of SAN causes significant changes in the acoustic structure of dolphin whistles. Additionally, changes in whistle parameters, in the presence of boats, appear to be related to the behavioural state of the dolphin group.
Show more [+] Less [-]Long-term fluctuations in Cystoseira populations along the west Istrian Coast (Croatia) related to eutrophication patterns in the northern Adriatic Sea Full text
2016
Iveša, Ljiljana | Djakovac, Tamara | Devescovi, Massimo
An exploration of historical data suggested that eutrophication patterns might drive long-term fluctuations in Cystoseira populations along the west Istrian Coast (northern Adriatic Sea, Croatia). The regimes of northern Italian rivers, which flow approximately 100km west of the study area, mainly modulate the eutrophication levels of the northern Adriatic Sea. A regression of Cystoseira populations from the 1970s through the 1990s corresponded to increased levels of eutrophication in the study area. During the late 1990s, the density of sea urchins, which are efficacious macroalgal predators, decreased, likely due to an intense formation of pelagic mucilage aggregates that resulted in mass mortality episodes of macrozoobenthic species. During the 2000–2013 period, an oligotrophication of the northern Adriatic formed the basis for the recovery of Cystoseira taxa, whose abundances from 2009 to 2013 were similar to those characterising the most flourishing Mediterranean Cystoseira assemblages.
Show more [+] Less [-]Baseline concentration of Polonium-210 (210Po) in tuna fish Full text
2016
Khan, M Feroz | Wesley, S Godwin
Several species of tuna fish were analyzed for 210Po content in their edible muscle tissues. This study was carried out as a part of baseline data generation around a large nuclear power plant situated at Kudankulam, southeast coast of India. The concentration of 210Po in the muscle tissue ranged from 40.9±5.2 to 92.5±7.9Bq/kg of fresh fish, and the highest activity was recorded for the tuna Euthynnus affinis and the lowest for Auxis thazard. The committed effective dose to the local residents was calculated to be 62.7–141.8μSvyear−1.
Show more [+] Less [-]A review of polymer nanofibres by electrospinning and their application in oil–water separation for cleaning up marine oil spills Full text
2016
Sarbatly, Rosalam | Krishnaiah, Duduku | Kamin, Zykamilia
The growths of oil and gas exploration and production activities have increased environmental problems, such as oil spillage and the resulting pollution. The study of the methods for cleaning up oil spills is a critical issue to protect the environment. Various techniques are available to contain oil spills, but they are typically time consuming, energy inefficient and create secondary pollution. The use of a sorbent, such as a nanofibre sorbent, is a technique for controlling oil spills because of its good physical and oil sorption properties. This review discusses about the application of nanofibre sorbent for oil removal from water and its current developments. With their unique physical and mechanical properties coupled with their very high surface area and small pore sizes, nanofibre sorbents are alternative materials for cleaning up oil spills.
Show more [+] Less [-]Proteomic analysis of bleached and unbleached Acropora palmata, a threatened coral species of the Caribbean Full text
2016
Ricaurte, Martha | Schizas, Nikolaos V. | Ciborowski, Paweł | Boukli, Nawal M.
There has been an increase in the scale and frequency of coral bleaching around the world due mainly to changes in sea temperature. This may occur at large scales, often resulting in significant decline in coral coverage. In order to understand the molecular and cellular basis of the ever-increasing incidence of coral bleaching, we have undertaken a comparative proteomic approach with the endangered Caribbean coral Acropora palmata. Using a proteomic tandem mass spectrometry approach, we identified 285 and 321 expressed protein signatures in bleached and unbleached A. palmata colonies, respectively, in southwestern Puerto Rico. Overall the expression level of 38 key proteins was significantly different between bleached and unbleached corals. A wide range of proteins was detected and categorized, including transcription factors involved mainly in heat stress/UV responses, immunity, apoptosis, biomineralization, the cytoskeleton, and endo–exophagocytosis. The results suggest that for bleached A. palmata, there was an induced differential protein expression response compared with those colonies that did not bleach under the same environmental conditions.
Show more [+] Less [-]Numerical evaluation of the use of granulated coal ash to reduce an oxygen-deficient water mass Full text
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.
Show more [+] Less [-]PCBs and OCPs in fish along coastal fisheries in China: Distribution and health risk assessment Full text
2016
Pan, Hui | Geng, Jingjing | Qin, Yukun | Tou, Feiyun | Zhou, Junliang | Liu, Min | Yang, Yi
PCBs and OCPs were analyzed in fish (bass) taken along Chinese coastal fisheries. In the bass muscle, PCB, DDT and HCH concentrations were in the range of 1.02–2.2ng/g, 0.44–1.74 and 2.84–106.11ng/gww, respectively. Spatial distribution showed that the concentrations of target contaminants in bass from south fisheries were in general much lower than those from north fisheries in China. The ratios of OCP congeners suggested that technical DDT was not the main input and a recent usage of lindane or old technical HCH residuals could be the source of HCHs. The OCC concentrations in liver (127–442.43ng/gww) from selected samples were 8–12 and 10–14 times higher than those in gills and muscles, respectively. Based on the maximum allowable fish assumption rate (CRlim and CRmm), it could cause human health risk, by consuming bass samples taken from highly contaminated fisheries including QD and ST.
Show more [+] Less [-]Sources and sinks of microplastics in Canadian Lake Ontario nearshore, tributary and beach sediments Full text
2016
Ballent, Anika | Corcoran, Patricia L. | Madden, Odile | Helm, Paul A. | Longstaffe, Fred J.
Microplastics contamination of Lake Ontario sediments is investigated with the aim of identifying distribution patterns and hotspots in nearshore, tributary and beach depositional environments. Microplastics are concentrated in nearshore sediments in the vicinity of urban and industrial regions. In Humber Bay and Toronto Harbour microplastic concentrations were consistently >500 particles per kg dry sediment. Maximum concentrations of ~28,000 particles per kg dry sediment were determined in Etobicoke Creek. The microplastic particles were primarily fibres and fragments <2mm in size. Both low- and high-density plastics were identified using Raman spectroscopy. We provide a baseline for future monitoring and discuss potential sources of microplastics in terms of how and where to implement preventative measures to reduce the contaminant influx. Although the impacts of microplastics contamination on ecosystem health and functioning is uncertain, understanding, monitoring and preventing further microplastics contamination in Lake Ontario and the other Great Lakes is crucial.
Show more [+] Less [-]Environmental genotoxicity assessment along the transport routes of chemical munitions leading to the dumping areas in the Baltic Sea Full text
2016
Baršienė, Janina | Butrimavičienė, Laura | Grygiel, Włodzimierz | Stunžėnas, Virmantas | Valskienė, Roberta | Greiciūnaitė, Janina | Stankevičiūtė, Milda
The frequencies of micronuclei (MN), nuclear buds (NB) and nuclear buds on filament (NBf) were examined in 660 specimens of herring (Clupea harengus) collected in 2009–2014 at 65 study stations located mainly along the chemical munition transport routes in the Baltic Sea. The frequency of nuclear abnormalities was strongly increased in herring caught at four stations located close to chemical munition dumping sites, or CWAs — substances (chemical warfare agents) in sediments. Significant increase of MN, NB and NBf was observed in fish caught November 2010–2013 compared to 2009. The most significantly increased genotoxicity responses were recorded in fish caught at stations along CW (chemical weapons) transport routes, close to the Bornholm CW dumping area, in zones with CWAs in sediments and with oil–gas platforms.
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