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T-PAH contamination in Mediterranean mussels (Mytilus galloprovincialis, Lamarck, 1819) at various stations of the Turkish Straits System Full text
2014
Balcıoğlu, Esra Billur | Aksu, Abdullah | Balkıs, Nuray | Öztürk, Bayram
Mussels (Mytilus galloprovincialis) from the Turkish Straits Systems were analyzed for sixteen parent polycyclic aromatic hydrocarbon (PAH) contents by high performance liquid chromatography (HPLC). This marine organism was selected because of its multitude, wide distribution, being bio indicator for the pollution and consumption by humans. Total PAH concentrations ranged from 1.2 to 589μgg−1 in Istanbul Strait, 0.94–36.4μgg−1 in Marmara Sea and 0.4–47.9μgg−1 in Çanakkale Strait during the samplings. According to the results Istanbul and Çanakkale Straits are more polluted than the Marmara Sea.
Show more [+] Less [-]Distribution and sources of polycyclic aromatic hydrocarbons in the surface sediments of Gorgan Bay, Caspian Sea Full text
2014
Araghi, Peyman Eghtesadi | Bastami, Kazem Darvish | Rahmanpoor, Shirin
The level and source of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments from the Gorgan Bay, Caspian Sea. The sum of 16 PAHs (ΣPAH16) concentrations varied from 107.87 to 516.18ngg−1dry weight, with average value of 270.96±150.47ngg−1dry weight. Ecological risk assessment of PAHs, indicated that adverse biological effects caused by acenaphthene, naphthalene, fluoranthene and Pyrene occasionally and frequently may take place in the sediments of Gorgan Bay. PAHs source identification demonstrated that the PAHs come from mixed and pyrogenic origin.
Show more [+] Less [-]Spatial variation, environmental assessment and source identification of heavy metals in sediments of the Yangtze River Estuary Full text
2014
Wang, Jiawei | Liu, Ruimin | Zhang, Peipei | Yu, Wenwen | Shen, Zhenyao | Feng, Chenghong
In order to analyze the spatial distribution patterns, pollution sources and ecological risks of heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn), 30 sediment samples were taken from in the Yangtze River Estuary (YRE). The results indicated that the contamination ranking of heavy metals was As>Cr>Cd>Ni>Mn>Pb>Zn>Cu. In the various areas, the pollution magnitude decreased as follows: adjacent sea>river mouth>inner-region. Compared to data published for other regions, the YRE data indicated that the sediment was not severely contaminated by heavy metals. In the YRE, natural and anthropogenic inputs dominated the distribution patterns of the heavy metals. Beyond that, the hydrodynamic conditions, such as the Taiwan warm current, coastal current and Yangtze diluted water, also caused distribution variations in the study areas.
Show more [+] Less [-]From a millennium base line to 2012: Beach litter changes in Wales Full text
2014
Williams, A.T. | Randerson, P. | Alharbi, O.A.
Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 2012, via a standard seven category checklist. Fourteen resorts, 2 urban, 11 village, 15 rural 3 remote, were graded, A to D. A grade beach numbers changed from 5 to19; B, 27 to 24; C, 9 to 2; D, 4 to 0, many beaches maintaining their current status. Assuming trend continuance within the next 12years, the A:B grade ratio would approach equilibrium of 44:56, with no grade C or D beaches. Recreational litter was ubiquitous; fishing materials prevalent along Cardigan Bay. New water treatment plant investment reduced sewage related debris. Despite apparent increased awareness of beach litter, improving visitor behaviour through information/education should be a future priority. Removing a few gross items could improve beach grades at little cost to local authorities and benefits to the Welsh economy.
Show more [+] Less [-]Comparison of number, surface area and volume distributions of particles emitted from a multipoint port fuel injection car and a gasoline direct injection car Full text
2014
Lv, Gang | Song, Chong–lin | Pan, Suo–zhu | Gao, Jun–hua | Cao, Xiao–feng
A chassis dynamometer study was conducted to compare the characteristics of particle emissions from a port fuel injection (PFI) and a gasoline direct injection (GDI) car, both of which comply with Euro 4 exhaust emission standards. Experiments were carried out over the New European Driving Cycle (NEDC), the ECE–15 segments, the period from 0 to 49 s within the NEDC procedure (FSE) and the Extra Urban Driving Cycle segment. Exhaust particles were characterized in terms of the particle number, surface area, volume and size distributions between 30nm and 1μm. Under the NEDC, the GDI car had particle emissions weighted by particle number, surface area and volume that were 56–2 739% higher than the emissions from the PFI car in the range of particle size measured, and the particle number, volume and surface area emissions per km for the GDI car are respectively 5.3, 9.0 and 14.6 times higher than those for the PFI car. Among the testing conditions employed, the highest concentrations of average particle number, surface area and volume were found in the FSE, and the particle number, surface area and volume for the GDI car were respectively 9.5, 33.2 and 39.8 times higher than those for the PFI car. Moreover, the peak of the particle size distributions for the PFI car was toward a smaller size, while that for the GDI was toward a larger size, indicating that particles emitted by the PFI car are much smaller than those emitted by the GDI car.
Show more [+] Less [-]Towards a predictive model to assess the natural position of the Posidonia oceanica seagrass meadows upper limit Full text
2014
Vacchi, Matteo | Montefalcone, Monica | Schiaffino, Chiara F. | Parravicini, Valeriano | Bianchi, Carlo Nike | Morri, Carla | Ferrari, Marco
The upper portion of the meadows of the protected Mediterranean seagrass Posidonia oceanica occurs in the region of the seafloor mostly affected by surf-related effects. Evaluation of its status is part of monitoring programs, but proper conclusions are difficult to draw due to the lack of definite reference conditions. Comparing the position of the meadow upper limit with the beach morphodynamics (i.e. the distinctive type of beach produced by topography and wave climate) provided evidence that the natural landwards extension of meadows can be predicted. An innovative model was therefore developed in order to locate the region of the seafloor where the meadow upper limit should lie in natural conditions (i.e. those governed only by hydrodynamics, in absence of significant anthropogenic impact). This predictive model was validated in additional sites, which showed perfect agreement between predictions and observations. This makes the model a valuable tool for coastal management.
Show more [+] Less [-]History of human activity in coastal southern Brazil from sediment Full text
2014
Niencheski, L.F. | Moore, W.S. | Windom, H.L.
This study reports results of analysis of sediment cores collected from the Patos Lagoon estuary. This estuary receives materials from land runoff into Patos and Mirim lagoons and from exchange with the adjacent South Atlantic Ocean through a narrow inlet. Sediment from these sources is mostly natural, but additional contributions associated with source/activities related to the port of Rio Grande. The aim of this study was to estimate rates of accumulation of the sediments and to assess the significance of metal inputs from these activities relative to natural inputs. Our results indicate an average sedimentation rate of 0.3cm/yr and that the transport of suspended solids from offshore sources into the estuary was enhanced after the deepening of the channel and construction of the breakwaters (in the early 1900). Results for metal accumulation in these sediments suggest that there have been only minor enrichments which can be attributed to anthropogenic sources.
Show more [+] Less [-]Effect of glyphosate-based herbicide on early life stages of Java medaka (Oryzias javanicus): A potential tropical test fish Full text
2014
Yusof, Shahrizad | Ismail, Ahmad | Alias, Mohamad Shafiq
Glyphosate is globally a widely used herbicide, yet there is little information on their toxicity to marine fishes. Java medaka, a small tropical fish native to coastal areas in several Southeast Asian countries, is viewed as a suitable candidate for toxicity test and thus was used for this study. Java medaka adults were cultured in the laboratory and the fertilized eggs of the F2 generation were exposed to different concentrations of glyphosate-based herbicide (100, 200, 300, 400 and 500ppm) until they hatched. The survival and hatching rates of the embryos, changes in the heart rate and morphological impairments were recorded. Generally, survival and hatching percentage decreased as glyphosate concentration increased. Absence of pectoral fin(s) and cornea, permanently bent tail, irregular shaped abdomen, and cell disruption in the fin, head and abdomen are among the common teratogenic effects observed. Furthermore, risk factor also increased with the increased in glyphosate concentrations.
Show more [+] Less [-]Suspended microplastics in the surface water of the Yangtze Estuary System, China: First observations on occurrence, distribution Full text
2014
Zhao, Shiye | Zhu, Lixin | Wang, Teng | Li, Daoji
Levels of microplastics (MPs) in China are completely unknown. This study characterizes suspended MPs quantitatively and qualitatively for the Yangtze Estuary and East China Sea. MPs were extracted via a floatation method. MPs were counted and categorized according to shape and size under a stereomicroscope. The MP densities were 4137.3±2461.5 and 0.167±0.138n/m3, respectively, in the estuarine and the sea samples. Plastic abundances varied significantly in the estuary. Higher densities in three sea trawls confirmed that rivers were the important sources of MP to the marine environment. Plastic particles (>5mm) were observed with a maximum size of 12.46mm, but MPs (0.5–5mm) constituted more than 90% by number of items. The most frequent geometries were fibres, followed by granules and films. Plastic spherules occurred sparsely. Transparent and coloured plastics comprised the majority of the particles. This study provides clues in understanding the fate and potential sources of MPs.
Show more [+] Less [-]A three-step model to assess shoreline and offshore susceptibility to oil spills: The South Aegean (Crete) as an analogue for confined marine basins Full text
2014
Alves, Tiago M. | Kokinou, Eleni | Zodiatis, George
This study combines bathymetric, geomorphological, geological data and oil spill predictions to model the impact of oil spills in two accident scenarios from offshore Crete, Eastern Mediterranean. The aim is to present a new three-step method of use by emergency teams and local authorities in the assessment of shoreline and offshore susceptibility to oil spills. The three-step method comprises: (1) real-time analyses of bathymetric, geomorphological, geological and oceanographic data; (2) oil dispersion simulations under known wind and sea current conditions; and (3) the compilation of final hazard maps based on information from (1) and (2) and on shoreline susceptibility data. The results in this paper show that zones of high to very-high susceptibility around the island of Crete are related to: (a) offshore bathymetric features, including the presence of offshore scarps and seamounts; (b) shoreline geology, and (c) the presence near the shore of sedimentary basins filled with unconsolidated deposits of high permeability. Oil spills, under particular weather and oceanographic conditions, may quickly spread and reach the shoreline 5–96h after the initial accident. As a corollary of this work, we present the South Aegean region around Crete as a valid case-study for confined marine basins, narrow seaways, or interior seas around island groups.
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