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Seasonal dynamics of marine litter along the Bulgarian Black Sea coast Texte intégral
2017
Simeonova, Anna | Chuturkova, Rozalina | Yaneva, Velika
In this study marine litter (ML) surveys were conducted in 8 beaches along the Bulgarian Black Sea coastline within 4 seasons for 2015–2016. The monitoring applied OSPAR guideline, classifying ML in eight categories and 167 types. The results exhibited predominance of artificial polymer materials - 84.3%. ML densities ranged from 0.0587±0.005 to 0.1343±0.008 n/m2, highest on the urban beaches. The seasonal dynamics of most top 10 ML showed highest quantities in summer than the other seasons, as the differences are of high statistical significance (0.001≤P≤0.05). Top 1 ML item for most of the beaches was cigarette butts and filters reaching 1008±10.58 nos. in summer and from 19±3.41 to 89±7.81 nos. during the rest of the seasons (P<0.001). For the pronounced seasonality contributed the recreational activities, increased tourist flow and the wild camping. The investigation will enrich data scarcity for Descriptor 10 “Marine litter”.
Afficher plus [+] Moins [-]Degradation and Fate of Pharmaceutically Active Contaminants by Advanced Oxidation Processes Texte intégral
2017
Alharbi, Sultan K. | Price, William E.
The purpose of this review is to investigate the use of advanced oxidation processes (AOPs) including ozonation, UV photolysis, Fenton-type processes, UV/H₂O₂, and other photocatalytic processes to degrade persistent pharmaceutically active contaminants in water. The review focuses on four common pharmaceuticals carbamazepine (CBZ), diclofenac (DCF), sulfamethoxazole (SMX), and trimethoprim (TMP) which are used as exemplars. Insights into the removal efficiency of each compound by AOPs under various applied conditions are systematically elucidated. This review also investigates the fate of these pharmaceuticals during treatment by advanced oxidation treatment. The effectiveness of AOP processes for the degradation of pharmaceuticals varies significantly, depending on factors such as the nature of the process itself, operating conditions, and the target compound. Ozone can completely remove all four pharmaceuticals. By contrast, direct UV photolysis was effective for the removal of DCF and SMX, whereas the combination with H₂O₂ was essential to improve CBZ and TMP removal. In addition, a large number of transformation products were frequently detected during the degradation of the selected pharmaceuticals by AOPs. In addition, it has been confirmed that several transformation products were more resistant toward the applied AOPs than their original parent compounds. A major challenge with the use of AOPs for the degradation of the selected pharmaceutically active contaminants is the formation of by-products that are often more persistent than the original contaminants. Therefore, the existence of transformation products must be essentially investigated after the treatment of target pharmaceutical contaminants by AOPs in order to evaluate the effectiveness of the applied technique.
Afficher plus [+] Moins [-]Shipping noise in a dynamic sea: a case study of grey seals in the Celtic Sea Texte intégral
2017
Chen, F. | Shapiro, G.I. | Bennett, K.A. | Ingram, S.N. | Thompson, D. | Vincent, C. | Russell, D.J.F. | Embling, C.B.
Shipping noise is a threat to marine wildlife. Grey seals are benthic foragers, and thus experience acoustic noise throughout the water column, which makes them a good model species for a case study of the potential impacts of shipping noise. We used ship track data from the Celtic Sea, seal track data and a coupled ocean-acoustic modelling system to assess the noise exposure of grey seals along their tracks. It was found that the animals experience step changes in sound levels up to ~20dB at a frequency of 125Hz, and ~10dB on average over 10–1000Hz when they dive through the thermocline, particularly during summer. Our results showed large seasonal differences in the noise level experienced by the seals. These results reveal the actual noise exposure by the animals and could help in marine spatial planning.
Afficher plus [+] Moins [-]Operational oil spill trajectory modelling using HF radar currents: A northwest European continental shelf case study Texte intégral
2017
Abascal, Ana J. | Sánchez, Jorge | Chiri, Helios | Ferrer, María I. | Cárdenas, Mar | Gallego, Alejandro | Castanedo, Sonia | Medina, Raúl | Alonso-Martirena, Andrés | Berx, Barbara | Turrell, William R. | Hughes, Sarah L.
This paper presents a novel operational oil spill modelling system based on HF radar currents, implemented in a northwest European shelf sea. The system integrates Open Modal Analysis (OMA), Short Term Prediction algorithms (STPS) and an oil spill model to simulate oil spill trajectories. A set of 18 buoys was used to assess the accuracy of the system for trajectory forecast and to evaluate the benefits of HF radar data compared to the use of currents from a hydrodynamic model (HDM). The results showed that simulated trajectories using OMA currents were more accurate than those obtained using a HDM. After 48h the mean error was reduced by 40%. The forecast skill of the STPS method was valid up to 6h ahead. The analysis performed shows the benefits of HF radar data for operational oil spill modelling, which could be easily implemented in other regions with HF radar coverage.
Afficher plus [+] Moins [-]Heavy metal distribution in blood, liver and kidneys of Loggerhead (Caretta caretta) and Green (Chelonia mydas) sea turtles from the Northeast Mediterranean Sea Texte intégral
2017
Yipel, Mustafa | Tekeli, İbrahim Ozan | İşler, Cafer Tayer | Altuğ, Muhammed Enes
The aim of the present study was to determine the concentrations of the most investigated environmentally relevant heavy metals in two highly endangered sea turtle species (Caretta caretta and Chelonia mydas) from the important nesting area on the Northeast Mediterranean Sea. The highest mean concentration was of Fe, while Hg and Pb were lowest. All tissue concentrations of Al, As, Fe and Mn were significantly different between the species. In particular, As, Cd, Cu, Mn, Ni, Se, Zn concentrations were lower in Caretta caretta and Cd, Hg, Mn, Zn concentrations were lower in Chelonia mydas than those reported in other parts of the world. Compared to studies conductud in other parts of the Mediterranean, Cd was lower.
Afficher plus [+] Moins [-]Effect of the interaction between transplants of the epiphytic lichen Pseudevernia furfuracea L. (Zopf) and rainfall on the variation of element concentrations associated with the water-soluble part of atmospheric depositions Texte intégral
2017
Gallo, Luana | Corapi, Anna | Apollaro, Carmine | Vespasiano, Giovanni | Lucadamo, Lucio
Water Soluble Bulk Deposition (WSBD) and Water Soluble Leaching (WSL) from Pseudevernia furfuracea thalli transplanted in a anthropized zone were separately collected in four locations where weather stations were set up for monitoring rainfalls rate and daily temperature.The thalli were exposed for three months during which 13 major rainfalls took place. The concentrations of 15 elements (Al, V, Cr, Mn, Co, Ni, Cu, Zn, Mo, Pb, As, Cd, Ti, Sn, Sb) were measured as well in WSBD and WSL as in the lichen thalli at the end of the exposure period. The total bioaccumulation of each element was significantly correlated with its % representation in both the lichen input (WSBD) and output (WSL). Elements with a small water-soluble input-pool were mostly taken up by the thalli (output/input < 1). Among the elements with a high input-pool, Zn was nearly systematically taken up while Al and Mn were lost (output/input > 1). Al showed a significant direct correlation with the increase in mm and hours of rainfall (i.e. transition from net loss to net uptake) while Mn showed an inverse correlation (transition from net uptake to net loss), which may be due to element competition modulated by water-stimulated lichen physiology. Al was strongly bioaccumulated while Mn showed a slight increase in exposed thalli. This suggests that rainfall-induced loss can result in an underestimation by lichen biomonitoring of element concentrations in atmospheric deposition and an increase in the bioavailability of potential toxic elements for other environmental compartments.
Afficher plus [+] Moins [-]Long-term variation of the macrobenthic community and its relationship with environmental factors in the Yangtze River estuary and its adjacent area Texte intégral
2017
Yan, Jia | Xu, Yong | Sui, Jixing | Li, Xinzheng | Wang, Hongfa | Zhang, Baolin
Using data from four periods from 1959 to 2015, we report the long-term variation of the macrobenthic community in the Yangtze River estuary and its adjacent area. In total, 624 species were collected, and Polychaeta was the dominant group. Significant differences between the four periods were found. The CCA (canonical correspondence analysis) and RDA (redundancy analysis) results revealed that temperature, salinity, and depth significantly influenced the macrobenthic communities (89.6% of the species-environment relationship variance was explained by the first two axes of CCA and 94.3% was explained by RDA). The results of K-dominance curves (the elevation increased over time), ABC (abundance/biomass comparison) curves (the W value changed from 0.311 to 0.167 during 1959 to 2014–2015) and the Shannon-Wiener index (log base=2; 2.29–5.03 in 1959, 2.86–4.55 in 2000–2001, 2.28–4.56 in 2011–2012, and 1.79–4.43 in 2014–2015) showed that the ecological status of the benthic study area was deteriorating.
Afficher plus [+] Moins [-]Modeling oil spill trajectory in Bosphorus for contingency planning Texte intégral
2017
Bozkurtoğlu, Şafak Nur Ertürk
Bosphorus, is a strongly driven international maritime route between the Black Sea and the Sea of Marmara and is a high risk area for oil spill due to the heavy tanker traffic. In this study an oil spill trajectory model was developed for investigating the potential risks of accidental oil spills in Bosphorus. The proposed oil spill trajectory model combines the surface current velocity data obtained from a calibrated hydrodynamic model with the advection, spreading, and evaporation processes that are effective only on the sea surface and dominant for a couple of hours after the oil spill. Model simulations revealed that spilled oil reaches the shoreline on both sides of Bosphorus in <4h following the spill. We proposed locations for emergency intervention stations in Bosphorus which can be used to devise a suitable oil spill contingency plan to keep the adverse impacts of oil spills at minimum.
Afficher plus [+] Moins [-]Colour spectrum and resin-type determine the concentration and composition of Polycyclic Aromatic Hydrocarbons (PAHs) in plastic pellets Texte intégral
2017
Fisner, Mara | Majer, Alessandra | Taniguchi, Satie | Bícego, Márcia | Turra, Alexander | Gorman, Daniel
This study assessed the concentration and composition of Polycyclic Aromatic Hydrocarbons (PAHs) in plastic pellets, collected from sandy beaches and considered different resin and colour tones. Results showed that polyethylene pellets, while displaying a greater range of total PAH concentrations did not differ significantly from polypropylene pellets. More importantly, both resin types demonstrated predictable increases in total PAH across a spectrum of darkening colour tones. Multivariate comparisons of 36 PAH groups, further showed considerable variability across resin type and colour, with lighter coloured pellets comprising lower molecular weight, while darker pellets contained higher weight PAHs. Overall, we show predictable variation in PAH concentrations and compositions of plastic pellets of different ages and resin types that will directly influence the potential for toxicological effects. Our findings suggest that monitoring programs should take these attributes into account when assessing the environmental risks of microplastic contamination of marine and coastal habitats.
Afficher plus [+] Moins [-]The first assessment of marine debris in a Site of Community Importance in the north-western Adriatic Sea (Mediterranean Sea) Texte intégral
2017
Melli, Valentina | Angiolillo, Michela | Ronchi, Francesca | Canese, Simonepietro | Giovanardi, Otello | Querin, Stefano | Fortibuoni, Tomaso
At present, few studies have investigated the marine litter abundance, composition and distribution on rocky bottoms due to sampling constraints. We surveyed by means of the ROV imaging technique a system of biogenic rocky outcrops classified as a Site of Community Importance in the Adriatic Sea. A mean density of 3.3 (±1.8) items/100m2 was recorded, with a strong dominance of fishing- and aquaculture-related debris, accounting for 69.4% and 18.9% of the total, respectively. The abundance of litter over the rocky bottoms was significantly higher than that on soft substrates, and its spatial distribution proved to be related to hydrographic factors. Litter-fauna interactions were high, with most of the debris (65.7%) entangling or covering benthic organisms, in particular habitat constructors such as the endangered sea sponge Geodia cydonium. Unless appropriate measures are undertaken to address this problem, the abundance of marine litter in the area is likely to increase.
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