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Polycyclic aromatic and aliphatic hydrocarbons pollution at the coast of Aliağa (Turkey) ship recycling zone
2012
Neşer, Gökdeniz | Kontas, Aynur | Ünsalan, Deniz | Altay, Oya | Darılmaz, Enis | Uluturhan, Esin | Küçüksezgin, Filiz | Tekoğul, Nermin | Yercan, Funda
Aliağa Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in sediment of the Aliağa Bay were investigated to evaluate an environmental risk assessment from PAHs contamination in 2009–2010. Aliphatic and PAHs diagnostic ratios were showed to be mainly petroleum-originated and pyrolitic contaminations, respectively. The TEL/PEL analysis suggests that Aliağa sediments were likely to be contaminated by acutely toxic PAH compounds.
Mostrar más [+] Menos [-]Parasite communities in the red mullet, Mullus barbatus L., respond to small-scale variation in the levels of polychlorinated biphenyls in the Western Mediterranean
2012
Carreras-Aubets, Marta | Montero, Francisco Esteban | Kostadinova, Aneta | Carrassón, Maite
We examined parasite populations and communities in the Mediterranean sentinel fish species, Mullus barbatus, sampled at a small-scale PCB gradient at the shelf sediments off Catalonian coasts of the Western Mediterranean. A recurrent feature at both the population and community level was the differentiation of the samples along the increasing PCB levels simultaneously registered in the sediments. Both directly transmitted ectoparasites and endoparasites with complex life-cycles transmitted via food chains exhibited a decrease in abundance with the increase in PCB levels. Parasite numerical responses translated into significant differences in infracommunity structure with decreasing predictability associated with increasing PCB levels. The abundance of two species, the specialist Opecoeloides furcatus and the generalist nematode Hysterothylacium fabri, contributed substantially to the observed dissimilarity between infracommunity samples along the gradient. The observed parasite responses to moderate levels of pollution were simultaneously validated by both chemical monitoring and effect biomarkers.
Mostrar más [+] Menos [-]Molecular and biochemical biomarkers responses in the mussel Mytilus edulis collected from Southern Brazil coast
2012
Rola, Regina Coimbra | Monteiro, Maurício da Costa | Reis, Sérgio Renan da Silva | Sandrini, Juliana Zomer
Marine ecosystems are typically subjected to a variety of stressors containing complex xenobiotics mixtures. This study aims to evaluate the responses of molecular and biochemical biomarkers in the mussel Mytilus edulis providing data for environmental monitoring programs development in Southern Brazil. Mussels were collected at a polluted site, near Patos Lagoon outfall, and at a control site. Gills, muscle and mantle samples were used for biomarker determinations. Mussels collected at the polluted site significantly increased superoxide dismutase (SOD) and glutathione S-transferase (GST) activities and decreased catalase (CAT) activity. Moreover, an increase in sod1, gstπ and hsp70 mRNA expression was observed. Overall, biochemical and molecular biomarkers responses were observed, but these responses varied depending on the analyzed tissue. These results indicate possible contaminants effects on organisms and the need for effective environmental monitoring programs in this ecosystem.
Mostrar más [+] Menos [-]Centennial records of lead contamination in northern Atlantic bivalves (Arctica islandica)
2012
Krause-Nehring, Jacqueline | Brey, Thomas | Thorrold, Simon R.
In the study, we establish centennial records of anthropogenic lead pollution at different locations in the North Atlantic (Iceland, USA, and Europe) by means of lead deposited in shells of the long-lived bivalve Arctica islandica. Due to local oceanographic and geological conditions we conclude that the lead concentrations in the Icelandic shell reflect natural influxes of lead into Icelandic waters. In comparison, the lead profile of the US shell is clearly driven by anthropogenic lead emissions transported from the continent to the ocean by westerly surface winds. Lead concentrations in the European North Sea shell, in contrast, are dominantly driven by local lead sources resulting in a much less conspicuous 1970s gasoline lead peak. In conclusion, the lead profiles of the three shells are driven by different influxes of lead, and yet, all support the applicability of Pb/Ca analyses of A. islandica shells to reconstruct location specific anthropogenic lead pollution.
Mostrar más [+] Menos [-]Rapid increase in copper concentrations in a new marina, San Diego Bay
2012
Biggs, Trent W. | D’Anna, Heather
Concentrations of copper in water rose rapidly following the introduction of boats to a new marina in San Diego Bay. Two months after the marina reached half its capacity, a majority of water samples exceeded chronic and acute criteria for dissolved copper, and copper concentrations in several samples exceeded the highest concentrations observed in another marina that has been listed as an impaired water body. A box model suggested that a small fraction of the leached copper was sequestered in sediment. Copper concentrations in water entering the marina from the bay was more than half the chronic concentration limit, so only 50% of marina boat capacity could be accommodated without exceeding the chronic criterion more than 50% of the time. Copper concentrations in water may increase rapidly following boat introduction in small marinas, but could return to pre-introduction levels by controlling boat numbers or reducing use of copper-based paints.
Mostrar más [+] Menos [-]Adaptive thresholding algorithm based on SAR images and wind data to segment oil spills along the northwest coast of the Iberian Peninsula
2012
Mera, David | Cotos, José M. | Varela-Pet, José | Garcia-Pineda, Oscar
Satellite Synthetic Aperture Radar (SAR) has been established as a useful tool for detecting hydrocarbon spillage on the ocean’s surface. Several surveillance applications have been developed based on this technology. Environmental variables such as wind speed should be taken into account for better SAR image segmentation. This paper presents an adaptive thresholding algorithm for detecting oil spills based on SAR data and a wind field estimation as well as its implementation as a part of a functional prototype. The algorithm was adapted to an important shipping route off the Galician coast (northwest Iberian Peninsula) and was developed on the basis of confirmed oil spills. Image testing revealed 99.93% pixel labelling accuracy. By taking advantage of multi-core processor architecture, the prototype was optimized to get a nearly 30% improvement in processing time.
Mostrar más [+] Menos [-]Biomarkers responses in muscle of Senegal sole (Solea senegalensis) from a heavy metals and PAHs polluted estuary
2012
Oliva, Milagrosa | Perales, José Antonio | Gravato, Carlos | Guilhermino, Lucia | Galindo-Riaño, María Dolores
The biochemical responses in muscle, such as the enzymatic activities of acetylcholinesterase, lactate dehydrogenase and isocitrate dehydrogenase, were studied in sole (Solea senegalensis) collected in Huelva estuary (SW Spain), in the vicinity of a petrochemical and mining industry. The sampling sites showed different type and degree of pollution. The results demonstrated significant differences in muscle activities of AChE and IDH in Odiel and Tinto Rivers compared to control fish. LDH activity did not show any difference between sampling sites. Significant correlations were established between some biomarkers and heavy metals: AChE was correlated with Pb, Cd and Cu concentrations in water; IDH activity was correlated with Cd and Cu concentrations in water and As, Pb and Cd concentrations in sediments; LDH activity was correlated with As and Zn concentration in water and Cd concentration in sediment. Only one correlation was established between the biomarkers analysed and the concentrations of PAHs: benzo(b)fluoranthene concentration in sediment and IDH.
Mostrar más [+] Menos [-]Analysis of Pacific oyster larval proteome and its response to high-CO₂
2012
Dineshram, R. | Wong, Kelvin K.W. | Xiao, Shu | Yu, Ziniu | Qian, Pei Yuan | Thiyagarajan, Vengatesen
Most calcifying organisms show depressed metabolic, growth and calcification rates as symptoms to high-CO₂ due to ocean acidification (OA) process. Analysis of the global expression pattern of proteins (proteome analysis) represents a powerful tool to examine these physiological symptoms at molecular level, but its applications are inadequate. To address this knowledge gap, 2-DE coupled with mass spectrophotometer was used to compare the global protein expression pattern of oyster larvae exposed to ambient and to high-CO₂. Exposure to OA resulted in marked reduction of global protein expression with a decrease or loss of 71 proteins (18% of the expressed proteins in control), indicating a wide-spread depression of metabolic genes expression in larvae reared under OA. This is, to our knowledge, the first proteome analysis that provides insights into the link between physiological suppression and protein down-regulation under OA in oyster larvae.
Mostrar más [+] Menos [-]GhostNet marine debris survey in the Gulf of Alaska – Satellite guidance and aircraft observations
2012
Pichel, William G. | Veenstra, Timothy S. | Churnside, James H. | Arabini, Elena | Friedman, Karen S. | Foley, David G. | Brainard, Russell E. | Kiefer, Dale | Ogle, Simeon | Clemente-Colon, Pablo | Li, Xiaofeng
Marine debris, particularly debris that is composed of lost or abandoned fishing gear, is recognized as a serious threat to marine life, vessels, and coral reefs. The goal of the GhostNet project is the detection of derelict nets at sea through the use of weather and ocean models, drifting buoys and satellite imagery to locate convergent areas where nets are likely to collect, followed by airborne surveys with trained observers and remote sensing instruments to spot individual derelict nets. These components of GhostNet were first tested together in the field during a 14-day marine debris survey of the Gulf of Alaska in July and August 2003. Model, buoy, and satellite data were used in flight planning. A manned aircraft survey with visible and IR cameras and a LIDAR instrument located debris in the targeted locations, including 102 individual pieces of debris of anthropogenic or terrestrial origin.
Mostrar más [+] Menos [-]Quantifying potential propagule pressure of aquatic invasive species from the commercial shipping industry in Canada
2012
Lo, Veronica B. | Levings, Colin D. | Chan, Kai M.A.
We quantify and compare different measures of potential propagule pressure (PPP) of aquatic invasive species (AIS) from commercial vessels in Canada. We used ship arrivals and ballast water discharge volumes as proxies for PPP from ballast water organisms, and wetted surface area (WSA) as a proxy for hull fouling PPP, to determine their relative contributions to total PPP. For three regions studied, PPP proxies correlated significantly across ports and some vessel categories. Relative contributions of ship arrivals, ballast discharge, and WSAs to PPP, evidenced by non-significant correlations across these measures, varied across regions, ports, vessel types, and seasons. Flow-through (dominant on east and west coasts) and empty-refill (in Great Lakes-St. Lawrence region) were the major ballast water exchange methods employed by the vessels surveyed. These methods have different biological efficacy for AIS removal, influencing PPP. Our study illustrates benefits and limitations of using different PPP proxies to estimate invasion risk.
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