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Backwash process of marine macroplastics from a beach by nearshore currents around a submerged breakwater Full text
2015
Kataoka, Tomoya | Hinata, Hirofumi | Kato, Shigeru
A key factor for determining the residence time of macroplastics on a beach is the process by which the plastics are backwashed offshore (backwash process). Here, we deduced the backwash process of plastic fishing floats on Wadahama Beach based on the analysis of two-year mark-recapture experiments as well as nearshore current structures revealed by sequential images taken by za webcam installed at the edge of a cliff behind the beach. The analysis results revealed the occurrence of a combination of offshore currents and convergence of alongshore currents in the surf zone in storm events around a submerged breakwater off the northern part of the beach, where 48% of the backwashed floats were last found. We conclude that the majority of the floats on the beach were transported alongshore and tended to concentrate in the convergence zone, from where they were backwashed offshore by the nearshore currents generated in the events.
Show more [+] Less [-]Equilibrium passive sampling as a tool to study polycyclic aromatic hydrocarbons in Baltic Sea sediment pore-water systems Full text
2015
Lang, Susann-Cathrin | Hursthouse, Andrew | Mayer, Philipp | Kötke, Danjiela | Hand, Ines | Schulz-Bull, Detlef | Witt, Gesine
Solid Phase Microextraction (SPME) was applied to provide the first large scale dataset of freely dissolved concentrations for 9 polycyclic aromatic hydrocarbons (PAHs) in Baltic Sea sediment cores. Polydimethylsiloxane (PDMS) coated glass fibers were used for ex-situ equilibrium sampling followed by automated thermal desorption and GC–MS analysis. From the PAH concentrations in the fiber coating we examined (i) spatially resolved freely dissolved PAH concentrations (Cfree); (ii) baseline toxicity potential on the basis of chemical activities (a); (iii) site specific mixture compositions; (iv) diffusion gradients at the sediment water interface and within the sediment cores and (v) site specific distribution ratios. Contamination levels were low in the northern Baltic Sea, moderate to elevated in the Baltic Proper and highest in the Gulf of Finland. Chemical activities were well below levels expected to cause narcosis to benthos organisms. The SPME method is a very sensitive tool that opens new possibilities for studying the PAHs at trace levels in marine environments.
Show more [+] Less [-]Participation in ICZM initiatives: Critical aspects and lessons learnt from the Mediterranean and Black Sea experiences Full text
2015
Soriani, Stefano | Buono, Fabrizia | Tonino, Marco | Camuffo, Monica
Public participation is recognized as a necessary tool to ensure a successful implementation of Integrated Coastal Zone Management (ICZM) strategies and plans. This paper, based on the experiences carried out in the Mediterranean and in the Black Sea within the EU FP7 project PEGASO, presents some critical aspects and lessons learnt regarding participation in ICZM projects. The research shows that data availability, the complexity of data interpretation, an inadequate legal and cultural framework and the difficulties in promoting integration of all the components of coastal management within short term projects are all elements that if not properly considered since the beginning of the participatory process may hinder public participation effectiveness. Moreover the definition of the spatial scale of coastal phenomenon as well as the discrepancy between the local scale of coastal governance and the complex multi-scale nature of coastal systems remain highly critical aspects to be addressed.
Show more [+] Less [-]Bioassessment of marine sediment quality using meiofaunal assemblages in a semi-enclosed bay Full text
2015
Liu, Xiaoshou | Huang, Deming | Zhu, Yanmei | Chang, Tianyi | Liu, Qinghe | Huang, Li | Zhao, Wei | Lin, Kuixuan | Liu, Lusan
In order to assess marine sediment quality of a semi-enclosed bay, sediment and meiofaunal samples were analyzed at 35 stations in coastal waters of Bohai Bay, China. Concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn, Co and Mn) in sediment were measured and the Hakanson potential ecological risk index coupled with the ratio of nematodes to copepods (N/C ratio) was used. Results showed that the concentration of Mn was the highest while Cd was the main risk contributor. The Hakanson potential ecological risk index indicated that all pollutants posed low risks in the study area. However, the N/C ratio exhibited different results compared with Hakanson potential ecological risk index. BIOENV analysis identified the concentration of Ni and sediment grain size as the most important environmental variables influencing meiofaunal assemblages. The present study indicated that, in marine sediment quality assessments, meiofaunal assemblages should be involved besides pollutant concentrations.
Show more [+] Less [-]The assessment of the spatial and seasonal variability of chromophoric dissolved organic matter in the Southern Yellow Sea and the East China Sea Full text
2015
Su, Rongguo | Bai, Ying | Zhang, Chuansong | Shi, Xiaoyong
Samples of chromophoric dissolved organic matter (CDOM) from the Southern Yellow Sea (SYS) and the East China Sea (ECS) were evaluated by fluorescent Excitation Emission Matrix (EEM) combined with Parallel Factorial Analysis (PARAFAC). Three terrestrial humic-like components (C1, C2 and C3) and one autochthonous protein-like component (C4) were identified. As for seasonal variations, CDOM displayed the following order on the whole: summer>spring>autumn. The C1, C2 and C3 components were mainly dominated by terrestrial inputs and their spatial distributions and temporal variations also can be influenced by primary productivity of phytoplankton, microbial activities and photobleaching. C4 was produced by phytoplankton and microorganisms and consumed by marine bacteria, and besides its distribution was attributed to the influence of riverine inputs. Terrestrial inputs were the dominant sources of CDOM in the SYS and ECS.
Show more [+] Less [-]Spatial–temporal analysis of marine debris on beaches of Niterói, RJ, Brazil: Itaipu and Itacoatiara Full text
2015
Silva, Melanie Lopes da | Araújo, Fábio Vieira de | Castro, Rebeca Oliveira | Sales, Alessandro Souza
In many areas of the world, studies of marine debris are conducted with an emphasis on analyzing their composition, quantification and distribution on sandy beaches. However, in Brazil, studies are still restricted to some areas of the coast, and the quantities and the spatial and temporal patterns are unknown. To enhance the marine debris information in these areas, we selected the Itaipu and Itacoatiara beaches in Niterói, RJ, to collect, quantify and qualify the solid residues present in their sands. We collected 12 samples and recorded 118.39kg of residues in Itaipu and 62.94kg in Itacoatiara. At both beaches, the largest portion of debris was located on the upper part of the beach. Several debris items were related to food and drink consumption on the beaches, which indicated the contribution of beach users to pollution. Most of the debris was plastic. The greatest amount of debris was found at Itaipu in January and February and at Itacoatiara in January and March, months related to both the holiday season and abundant rainfall. The results demonstrated the necessity to implement an Environmental Education project for these areas to reduce its degradation.
Show more [+] Less [-]Sharks and people: Insight into the global practices of tourism operators and their attitudes to Shark behaviour Full text
2015
Richards, Kirsty | O’Leary, Bethan C. | Roberts, Callum M. | Ormond, Rupert | Gore, Mauvis | Hawkins, Julie P.
Shark tourism is a popular but controversial activity. We obtained insights into this industry via a global e-mailed questionnaire completed by 45 diving/snorkelling operators who advertised shark experiences (shark operators) and 49 who did not (non-shark operators). 42% of shark operators used an attractant to lure sharks and 93% stated they had a formal code of conduct which 86% enforced “very strictly”. While sharks were reported to normally ignore people, 9 operators had experienced troublesome behaviour from them. Whilst our research corroborates previous studies indicating minimal risk to humans from most shark encounters, a precautionary approach to provisioning is required to avoid potential ecological and societal effects of shark tourism. Codes of conduct should always stipulate acceptable diver behaviour and appropriate diver numbers and shark operators should have a moral responsibility to educate their customers about the need for shark conservation.
Show more [+] Less [-]Spatial and temporal distribution and risk assessment of polycyclic aromatic hydrocarbons in surface seawater from the Haikou Bay, China Full text
2015
Li, Yuhu | Li, Ping | Ma, Wandong | Song, Qingqing | Zhou, Hailong | Han, Qian | Diao, Xiaoping
Spatial and temporal distributions of 14 polycyclic aromatic hydrocarbons (PAHs) were investigated in surface waters of Haikou Bay, China from October 2013 to September 2014. The total PAHs concentrations ranged from 420.2 to 2539.1ngL−1 with the average value of 1016.3±455.8ngL−1, which were predominated by low molecular weight PAHs (2- and 3-ring PAHs). Moreover, PAHs displayed spatial and temporal variations in the concentration and composition pattern. Source analysis based on isomer ratios indicated that the PAHs mostly originated from petroleum and combustion processes. An eco-toxicological risk assessment showed that the potential risk of individual PAHs had reached moderate to high levels and the total concentrations of PAHs had also reached a relatively high level compared with previous studies. This study offers important information on the pollution levels of 14 PAHs in the surface waters of Haikou Bay and recommends that prevention and control of PAHs pollution should be implemented in the region.
Show more [+] Less [-]Response of a seagrass fish assemblage to improved wastewater treatment Full text
2015
Ourgaud, M. | Ruitton, S. | Bell, J.D. | Letourneur, Y. | Harmelin, J.G. | Harmelin-Vivien, M.L.
We compared the structure of a seagrass fish assemblage near a sewage outlet before and after improvements to wastewater treatment. To determine whether responses by the fish assemblage were due to changes in water quality or to other factors, comparisons were made with the structure of a fish assemblage from a nearby site unaffected by sewage effluent. Total species richness, density and biomass of fish, decreased at both sites over the 30-year period. An increase in mean trophic level near the sewage outlet following improvements in water quality indicated that wastewater treatment had another important effect. This result is consistent with the reductions in food webs supporting pelagic and benthic fishes that typically accompany decreases in nutrient inputs. Although improvements to wastewater treatment explained much of the variation in the structure of the fish assemblage at PC, our results also suggest that fishing and climate change, at both sites.
Show more [+] Less [-]Source apportionment analysis of airborne VOCs using positive matrix factorization in industrial and urban areas in Thailand Full text
2015
Saeaw, Neungrothai | Thepanondh, Sarawut
Airborne volatile organic compounds (VOCs) concentration data from monitoring stations in industrial and urban (Bangkok) area of Thailand were analyzed using Positive Matrix Factorization (PMF) to identify and elaborate on their source profiles. Analyzed data were obtained from those measured from January 2009 to December 2013 in the study area. The PMF was performed to estimate the contribution of specific source types to ambient concentrations. The most suitable number of factors for a dataset in this study was found to be eleven factors for compositions and characteristics of VOCs. Emission sources of VOCs in industrial area were classified into three to five groups based on their contribution. In industrial area, 42 to 57% of total VOC concentrations were contributed from mobile sources. Contribution to total VOCs concentration from industrial processes and household chemical usage were about 15 to 44% and 3 to 10%, respectively. Moreover, some species of VOCs particularly the ozone depleting substances such as Freon 11, Freon 114 and carbon tetrachloride were found as background concentration in ambient air. As for Bangkok, it was found that most of total VOC concentrations were contributed from mobile source emissions.
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