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Direct evidence of histopathological impacts of wastewater discharge on resident Antarctic fish (Trematomus bernacchii) at Davis Station, East Antarctica Полный текст
2014
Corbett, Patricia A. | King, Catherine K. | Stark, Jonathan S. | Mondon, Julie A.
During the 2009/2010 summer, a comprehensive environmental impact assessment (EIA) of the wastewater discharge at Davis Station, East Antarctica was completed. As part of this, histological alteration of gill and liver tissue in Antarctic Rock-cod (Trematomus bernacchii) from four sites along a spatial gradient from the wastewater outfall were assessed. All fish within 800m of the outfall exhibited significant histological changes in both tissues. Common pathologies observed in fish closest to the outfall include proliferation of epithelial cells with associated secondary lamellar fusion in the gills and multifocal granulomata with inflammation and necrosis as well as cysts in the liver. Fish from sites >800m from the outfall also exhibited alterations but to a lesser degree, with prevalence and severity decreasing with increasing distance from the outfall. This study highlights the value of histopathological investigations as part of EIAs and provides the first evidence of sub-lethal alteration associated with wastewater discharge in East Antarctica.
Показать больше [+] Меньше [-]Phytoplankton dynamics in the Gulf of Aqaba (Eilat, Red Sea): A simulation study of mariculture effects Полный текст
2014
Laiolo, Leonardo | Barausse, Alberto | Dubinsky, Z. (Zvy) | Palmeri, Luca | Goffredo, Stefano | Kamenir, Yury | Al-Najjar, Tariq | Iluz, David
The northern Gulf of Aqaba is an oligotrophic water body hosting valuable coral reefs. In the Gulf, phytoplankton dynamics are driven by an annual cycle of stratification and mixing. Superimposed on that fairly regular pattern was the establishment of a shallow-water fish-farm initiative that increased gradually until its activity was terminated in June 2008. Nutrient, water temperature, irradiation, phytoplankton data gathered in the area during the years 2007–2009, covering the peak of the fish-farm activity and its cessation, were analyzed by means of statistical analyses and ecological models of phytoplankton dynamics. Two datasets, one from an open water station and one next to the fish farms, were used. Results show that nutrient concentrations and, consequently, phytoplankton abundance and seasonal succession were radically altered by the pollution originating from the fish-farm in the sampling station closer to it, and also that the fish-farm might even have influenced the open water station.
Показать больше [+] Меньше [-]Bioaccumulation of trace elements in dominant mesozooplankton group inhabiting in the coastal regions of Indian Sundarban mangrove wetland Полный текст
2014
Bhattacharya, Bhaskar Deb | Hwang, Jiang-Shiou | Tseng, Li-Chun | Sarkar, Santosh Kumar | Rakshit, Dibyendu | Mitra, Soumita
Mesozooplankton (Body size 20–200μm) along with the surface water were collected from coastal regions of Sundarban, northeastern part of Bay of Bengal considering three seasons, namely premonsoon, monsoon and postmonsoon. Samples were analyzed for community structure and the dominant copepod species were further analyzed for trace metal concentration. In total, 50 copepods were identified (22 families and 43 genera). The dominant mesozooplankton species included 9 copepods and an epipelagic chaetognath, exhibited both spatial and seasonal variations. Metal concentration exhibited considerable inter-specific variations for the copepods and the mean concentrations were: Fe, 1350.2–51118.3μg/g; Al, 647.2–73019.1μg/g; Ni, 32.4–110.3μg/g; Mn, 122.8–1066.5μg/g; Pb, 0.04–97.5μg/g; Pb, 10.6–97.5μg/g; Cd, 4.2–21.6μg/g; Cu, 17.4–145.1μg/g; Zn, 225.7–1670.9μg/g; Cr, 21.7–194.3μg/g; Co, 1.32–111.1μg/g. Metal concentrations showed the following order: Sagitta bedoti>Coryceas danae>Oithona sp.>Eucalanus subcrassus>Labidocera euchaeta>Paracalanus parvus>Acartiella tortaniformis>Acartia spinicauda>Pseudocalanus serricaudatus.
Показать больше [+] Меньше [-]Levels and fate of perfluoroalkyl substances in beached plastic pellets and sediments collected from Greece Полный текст
2014
Llorca, Marta | Farré, Marinella | Karapanagioti, Hrissi K. | Barceló, Damià
Plastic debris damages marine wildlife and ecosystems becoming an important source of marine pollution. In addition, they can sorb, concentrate and stabilise contaminants acting as toxic carriers to the marine food web. In this context, the presence of 18 perfluoroalkyl substances (PFASs) in plastic pellets (n=5) and beach sediment (n=9) samples widely distributed around Greek coastal areas was assessed.The results, mainly, showed the sorption of PFASs onto pellet surface from surrounding water with concentrations from method limit of quantification to 115ng/kg for C5, C7, C8 and C10 carboxylic acids and C8 sulfonate acid. A similar pattern was found by comparing plastic pellets and sediment for the same sampling locations that could indicate a common origin of contamination in both types of samples. However, since the number of analysed samples is limited, a more comprehensive study with a higher number of samples should be performed in future research.
Показать больше [+] Меньше [-]Detection of Helicobacter pylori in the coastal waters of Georgia, Puerto Rico and Trinidad Полный текст
2014
Holman, Chelsea B. | Bachoon, D.S. | Otero, Ernesto | Ramsubhag, Adesh
Fecal pollution in the coastal marine environments was assessed at eleven sampling locations along the Georgia coast and Trinidad, and nine sites from Puerto-Rico. Membrane filtration (EPA method 1604 and method 1600) was utilized for Escherichia coli and enterococci enumeration at each location. Quantitative polymerase chain reaction (qPCR) amplification of the 16S ribosomal RNA gene was used to determine the presence of the Helicobacter pylori in marine samples. There was no significant correlation between the levels of E. coli, enterococci and H. pylori in these water samples. H. pylori was detected at four of the 31 locations sampled; Oak Grove Island and Village Creek Landing in Georgia, Maracas river in Trinidad, and Ceiba Creek in Puerto Rico. The study confirms the potential public health risk to humans due to the widespread distribution of H. pylori in subtropical and tropical costal marine waters.
Показать больше [+] Меньше [-]The effect of breakwaters on the structure of marine soft-bottom assemblages: A case study from a North-Western Mediterranean basin Полный текст
2014
Becchi, Claudia | Ortolani, Irene | Muir, Alexander | Cannicci, Stefano
This two-year study is the first attempt to analyse the ecological effects of breakwater systems on soft-bottom assemblages along the North Tyrrhenian coast. Differently from previous studies focusing on infauna of on-shore and off-shore sides, we compared the assemblages inhabiting the surrounding soft-bottoms not directly protected by the breakwaters, defining our sampling stations at varying distances from the breakwaters and at constant distance from the coast.Data collected revealed that abundance, species richness and M-AMBI ecological quality differed between northern and southern sides, and were related to distance from structures. Multivariate analyses of relationships between assemblages and abiotic characteristics support this hypothesis. The extension of these effects, that resulted to be weak and limited to a restricted area, could be a consequence of coastal current on local hydrodynamics. This study provides novel and critical information for the management of the coastal defence infrastructure spreading along the western coast of Italy.
Показать больше [+] Меньше [-]Unexpected abundance and long-term relative stability of the brown alga Cystoseira amentacea, hitherto regarded as a threatened species, in the north-western Mediterranean Sea Полный текст
2014
Thibaut, Thierry | Blanfuné, Aurélie | Markovic, Laurent | Verlaque, Marc | Boudouresque, Charles F. | Perret-Boudouresque, Michèle | Maćic, Vesna | Bottin, Lorraine
Cystoseira amentacea is a Mediterranean endemic alga thriving on very shallow rocky substrates. It has been considered as a threatened species, having experienced a steady decline and is therefore protected by international conventions. The historical distribution of the species has been assessed along the French Mediterranean coast, on the basis of 467 articles and herbarium vouchers. We have produced an accurate map of its current distribution and abundance along 1832km of coastline, through in situ surveys. C. amentacea was observed along 1125km of shoreline, including 33% of almost continuous or continuous belt. In most of its range, there is no evidence of loss, except in 4 areas of Provence, French Riviera and Corsica. A significant relation was found between the absence or low abundance of C. amentacea and the vicinity of ports and large sewage outfalls. The status of conservation of the species should therefore be reassessed.
Показать больше [+] Меньше [-]Responses of calcification of massive and encrusting corals to past, present, and near-future ocean carbon dioxide concentrations Полный текст
2014
Iguchi, Akira | Kumagai, Naoki H. | Nakamura, Takashi | Suzuki, Atsushi | Sakai, Keinan | Nojiri, Yukihiro
In this study, we report the acidification impact mimicking the pre-industrial, the present, and near-future oceans on calcification of two coral species (Porites australiensis, Isopora palifera) by using precise pCO2 control system which can produce acidified seawater under stable pCO2 values with low variations. In the analyses, we performed Bayesian modeling approaches incorporating the variations of pCO2 and compared the results between our modeling approach and classical statistical one. The results showed highest calcification rates in pre-industrial pCO2 level and gradual decreases of calcification in the near-future ocean acidification level, which suggests that ongoing and near-future ocean acidification would negatively impact coral calcification. In addition, it was expected that the variations of parameters of carbon chemistry may affect the inference of the best model on calcification responses to these parameters between Bayesian modeling approach and classical statistical one even under stable pCO2 values with low variations.
Показать больше [+] Меньше [-]Spatio-temporal pattern of community development in dredged material used for habitat enhancement: A study case in a brackish lagoon Полный текст
2014
Munari, C. | Mistri, M.
Dredged material is a potential resource for beneficial use for create/improve subtidal habitats. In a northwestern Adriatic lagoon, dredged sand was placed in inner areas with the management objective of improving the characteristics of the muddy areas being recharged. With this study we investigated the recolonization dynamics of benthic communities following the placement of dredged sand in a microtidal lagoon. The disposal of dredged sand had an immediate and negative effect on resident fauna. After an initial reduction, benthic communities followed different recovery pathways. One year after disposal, we recorded an almost complete recovery of the benthic invertebrates in terms of univariate parameters. Despite multivariate analyses still showed significantly different community structures, the trajectories of recovery for disposal areas converged towards the same basin of attraction of control areas. The ecological quality of sites, assessed with benthic indices, did not improve, thus no new beneficial habitat was created for macrobenthos.
Показать больше [+] Меньше [-]Relationship between sources and patterns of VOCs in indoor air Полный текст
2014
Rösch, Carolin | Kohajda, Tibor | Röder, Stefan | Bergen, Martin von | Schlink, Uwe
People spend most of their daytime in indoor environments. Their activities influence the composition of the indoor air by emitting volatile organic compounds (VOCs). The increasing number of different VOCs became the focus of attention in recent years as the question arises from the relationship between exposure to air pollutants and diseases. The present study of flats in Leipzig (Germany) is based on measurements of 60 different VOCs and is unique in the field of indoor air quality due to its enormous size of samples (n=2 242) and questionnaire data. The main purpose of our analysis was to identify the sources and patterns that characterize airborne VOCs in occupied flats. We combined two methods, principal components analysis (PCA) and non–negative matrix factorization (NMF), to assign compounds to their origin and to understand the coinstantaneous existence of several VOCs. PCA clustering provided a source apportionment and yielded 10 principal components (PCs) with an explained variance of 72%. However, real indoor air quality is often affected by combined sources. NMF reveals characteristic compositions of VOCs in indoor environments and emphasizes that constantly recurring structures are not single sources, but rather fusions of them, so called patterns. Interpreting these sources, we realized that homes were strongly influenced by ventilation, human activities, furnishings, natural processes (such as solar radiation) or their combinations. The very large set of samples and the combination with questionnaires applied on this comprehensive assessment of VOCs allows generalizing the results to homes in middle–scale cities with minor industrial pollution. As a conclusion, single VOC–dose–response relationships are inopportune for situations when indoor sources occur in combination. Further studies are necessary to assess associated health risks.
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