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Significance of groundwater discharge along the coast of Poland as a source of dissolved metals to the southern Baltic Sea 全文
2016
Szymczycha, Beata | Kroeger, Kevin D. | Pempkowiak, Janusz
Fluxes of dissolved trace metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) via groundwater discharge along the southern Baltic Sea have been assessed for the first time. Dissolved metal concentrations in groundwater samples were less variable than in seawater and were generally one or two orders of magnitude higher: Cd (2.1–2.8nmolL−1), Co (8.70–8.76nmolL−1), Cr (18.1–18.5nmolL−1), Mn (2.4–2.8μmolL−1), Pb (1.2–1.5nmolL−1), Zn (33.1–34.0nmolL−1). Concentrations of Cu (0.5–0.8nmolL−1) and Ni (4.9–5.8nmolL−1) were, respectively, 32 and 4 times lower, than in seawater. Groundwater-derived trace metal fluxes constitute 93% for Cd, 80% for Co, 91% for Cr, 6% for Cu, 66% for Mn, 4% for Ni, 70% for Pb and 93% for Zn of the total freshwater trace metal flux to the Bay of Puck. Groundwater-seawater mixing, redox conditions and Mn-cycling are the main processes responsible for trace metal distribution in groundwater discharge sites.
显示更多 [+] 显示较少 [-]Spatial distribution and pollution evaluation of heavy metals in Yangtze estuary sediment 全文
2016
Liu, Ruimin | Men, Cong | Liu, Yongyan | Yu, Wenwen | Xu, Fei | Shen, Zhenyao
To analyze the spatial distribution patterns and ecological risks of heavy metals, 30 sediment samples were taken in the Yangtze River Estuary (YRE) in May 2011. The content of Al, As, Cr, Cu, Fe, Mn, Ni and Pb increased as follows: inner-region<river mouth<adjacent sea. According to Igeo and RI, As, Cr and Cd were the main pollutants. What is more, the greatest contaminated area appeared at the river mouth of the south branch of YRE. In Tucker 3, considering the fractions of metals, Mn turned to be the severest pollutant and As did not contribute too much to the contamination of the YRE. That was most probably because that Mn was closely related to the carbonate-associated (CARB) and As was related to organic-associated (OM) which is more stable than CARB. The fractions played an important role in the contamination assessment of heavy metals.
显示更多 [+] 显示较少 [-]Temporal and spatial changes in persistent organic pollutants in Vietnamese coastal waters detected from plastic resin pellets 全文
2016
Le, Dung Quang | Takada, Hideshige | Yamashita, Rei | Mizukawa, Kaoruko | Hosoda, Junki | Tuyet, Dao Anh
Plastic resin pellets collected at Minh Chau island and Ba Lat estuary between 2007 and 2014 in Vietnam were analyzed for dichloro-diphenyl-trichloroethanes (DDTs), polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs). The study was carried out as part of the International Pellet Watch program for monitoring the global distribution of persistent organic pollutants (POPs). Higher levels of DDTs compared to PCBs indicated agricultural inputs rather than industrial discharges in the region. Most POP concentrations on both beaches decreased over the period, with the exception of HCH isomers. Though the concentration of DDTs showed a drastic decline on both beaches between 2007/2008 and 2014, DDTs accounted for 60–80% of total DDTs, suggesting that there is still a fresh input of these chemicals in the region. This study strongly recommends further investigations to track temporal and spatial patterns of POP levels in the marine environment using plastic resin pellets.
显示更多 [+] 显示较少 [-]International law on ship recycling and its interface with EU law 全文
2016
Argüello Moncayo, Gabriela
The regulation on ship recycling at international and European Union (EU) level has transitioned from the realm of transboundary movement of wastes to a specialized regime, i.e., the Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships (2009) (Hong Kong Convention). Although this convention is not in force yet, the principal features of it have been incorporated in EU Regulation 1257/2013 on ship recycling. This paper examines the rationale behind developing a ship recycling regime, its disassociation from wastes, and the departure from the main principles of transboundary movement of wastes, such as the proximity principle, reduction of transboundary movement of wastes, and the prior informed consent procedure. While acknowledging some of the positive features of the emerging ship recycling, it is submitted that the Hong Kong Convention and EU Regulation 1257/2013 on ship recycling represent a step back in the regulation of ship recycling.
显示更多 [+] 显示较少 [-]Responses of bacterial and archaeal communities to nitrate stimulation after oil pollution in mangrove sediment revealed by Illumina sequencing 全文
2016
Wang, Lei | Huang, Xu | Zheng, Tian-Ling
This study aimed to investigate microbial responses to nitrate stimulation in oiled mangrove mesocosm. Both supplementary oil and nitrate changed the water and sediment chemical properties contributing to the shift of microbial communities. Denitrifying genes nirS and nirK were increased several times by the interaction of oil spiking and nitrate addition. Bacterial chao1 was reduced by oil spiking and further by nitrate stimulation, whereas archaeal chao1 was only inhibited by oil pollution on early time. Sampling depth explained most of variation and significantly impacted bacterial and archaeal communities, while oil pollution only significantly impacted bacterial communities (p<0.05). Despite explaining less variation, nitrate addition coupled with oil spiking enhanced the growth of hydrocarbon degraders in mangrove. The findings demonstrate the impacts of environmental factors and their interactions in shaping microbial communities during nitrate stimulation. Our study suggests introducing genera Desulfotignum and Marinobacter into oiled mangrove for bioaugmentation.
显示更多 [+] 显示较少 [-]Linkage between speciation of Cd in mangrove sediment and its bioaccumulation in total soft tissue of oyster from the west coast of India 全文
2016
Chakraborty, Parthasarathi | Ramteke, Darwin | Gadi, Subhadra Devi | Bardhan, Pratirupa
This study established a mechanistic linkage between Cd speciation and bioavailability in mangrove system from the west coast of India. High bioaccumulation of Cd was found in the oyster (Crassostrea sp.) even at low Cd loading in the bottom sediment. Bioaccumulation of Cd in the oyster gradually increased with the increasing concentrations of water soluble, exchangeable and carbonate/bicarbonate forms of Cd in the sediments. Fe/Mn oxyhydroxide phase was found to control Cd bioavailability in the sediment system. Cd-associated with sedimentary organic matter was bioavailable and organic ligands in the sediments were poor chelating agents for Cd. This study suggests that bioaccumulation of Cd in oyster (Crassostrea sp.) depends not on the total Cd concentration but on the speciation of Cd in the system.
显示更多 [+] 显示较少 [-]Regional approach to modeling the transport of floating plastic debris in the Adriatic Sea 全文
2016
Liubartseva, S. | Coppini, G. | Lecci, R. | Creti, S.
Sea surface concentrations of plastics and their fluxes onto coastlines are simulated over 2009–2015. Calculations incorporate combinations of terrestrial and maritime litter inputs, the Lagrangian model MEDSLIK-II forced by AFS ocean current simulations, and ECMWF wind analyses. With a relatively short particle half-life of 43.7days, the Adriatic Sea is defined as a highly dissipative basin where the shoreline is, by construction, the main sink of floating debris. Our model results show that the coastline of the Po Delta receives a plastic flux of approximately 70kg(kmday)-1. The most polluted sea surface area (>10gkm-2 floating debris) is represented by an elongated band shifted to the Italian coastline and narrowed from northwest to southeast. Evident seasonality is found in the calculated plastic concentration fields and the coastline fluxes. Complex source–receptor relationships among the basin's subregions are quantified in impact matrices.
显示更多 [+] 显示较少 [-]Towards an integrated approach to marine benthic monitoring 全文
2016
Barrio Froján, Christopher R.S. | Cooper, Keith M. | Bolam, Stefan G.
In the UK, most marine benthic monitoring is carried out in a piecemeal fashion, funded by different sectors of industry that utilise the marine environment under licence. Monitoring requirements are imposed by licence conditions, which can vary considerably between licences. The UK Government also conducts marine environmental surveys in support of its legislative commitments. The present investigation reviews these different monitoring approaches to highlight whether synergies between them could be developed into an integrated approach to marine benthic monitoring. An integrated approach would have ecological benefits, as greater consistency in sampling and analytical protocols would reduce uncertainty in the predictions of impact, and facilitate the assessment of Good Environmental Status under the Marine Strategy Framework Directive. The same approach would also be of financial benefit, as spatio-temporal duplication in sampling would be reduced, and the value of acquired data would be maximised, resulting in a more efficient and cost-effective approach.
显示更多 [+] 显示较少 [-]Spatial distribution of floating marine debris in offshore continental Portuguese waters 全文
2016
Sá, Sara | Bastos-Santos, Jorge | Araujo, Helder | Ferreira, Marisa | Duro, Virginia | Alves, Flávia | Panta-Ferreira, Bruno | Nicolau, Lídia | Eira, Catarina | Vingada, José
This study presents data on abundance and density of macro-floating marine debris (FMD), including their composition, spatial distribution and potential sources off continental Portugal. FMD were assessed by shipboard visual surveys covering ±252,833km2 until the 220nm limit. The FMD average density was 2.98items/km2 and abundance amounted to 752,740 items. Unidentified plastics constitute the major bulk of FMD (density=0.46items/km2; abundance=117,390 items), followed by styrofoam, derelict or lost materials from fisheries, paper/cardboard and wood material. The North sector of the area presents higher FMD diversity and abundances, probably as a result of the high number of navigation corridors and fisheries operating in that sector. Most FMD originate from local sources, namely discharges from vessels and derelict material from fisheries. Considering the identifiable items, cables and fishing lines were the only fishing related items among the top ten FMD items in Portuguese offshore waters.
显示更多 [+] 显示较少 [-]Occurrence and distribution of polycyclic aromatic hydrocarbons in mussels from the gulf of Naples, Tyrrhenian Sea, Italy 全文
2016
Mercogliano, Raffaelina | Santonicola, Serena | De Felice, Alessandra | Anastasio, Aniello | Murru, Nicoletta | Ferrante, Maria Carmela | Cortesi, Maria Luisa
To assess the potential impact of the industrial activity on food safety and risk for consumers, the aim of the study was to evaluate the levels of 14 polycyclic aromatic hydrocarbons (PAH) in 69 samples of wild and farm Mytilus galloprovincialis, collected in sites of coast of Gulf of Naples, Tyrrhenian Sea.All hydrocarbons were found in samples. Higher levels of pyrolytic PAHs were in wild than in farm mussels. Benzo(a)pyrene exceeded the Regulation (EC) n.835/11 levels of 1μg/kg in 15 samples (71.42%) of wild and 25 samples (65.79%) of farm mussels. System of sum of 4 hydrocarbons exceeded the law level in 15 samples (71.42%) of wild and 21 samples (55.26%) of farm mussels. Wild mussel levels showed a potential impact of pyrolytic sources of PAH on food safety. Occurrence of carcinogenic PAHs should be a cause for concern, in areas where the mussels are being farmed for human consumption.
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