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Biomarkers responses in muscle of Senegal sole (Solea senegalensis) from a heavy metals and PAHs polluted estuary Full text
2012
Oliva, Milagrosa | Perales, José Antonio | Gravato, Carlos | Guilhermino, Lucia | Galindo-Riaño, María Dolores
The biochemical responses in muscle, such as the enzymatic activities of acetylcholinesterase, lactate dehydrogenase and isocitrate dehydrogenase, were studied in sole (Solea senegalensis) collected in Huelva estuary (SW Spain), in the vicinity of a petrochemical and mining industry. The sampling sites showed different type and degree of pollution. The results demonstrated significant differences in muscle activities of AChE and IDH in Odiel and Tinto Rivers compared to control fish. LDH activity did not show any difference between sampling sites. Significant correlations were established between some biomarkers and heavy metals: AChE was correlated with Pb, Cd and Cu concentrations in water; IDH activity was correlated with Cd and Cu concentrations in water and As, Pb and Cd concentrations in sediments; LDH activity was correlated with As and Zn concentration in water and Cd concentration in sediment. Only one correlation was established between the biomarkers analysed and the concentrations of PAHs: benzo(b)fluoranthene concentration in sediment and IDH.
Show more [+] Less [-]Environmentally safe areas and routes in the Baltic proper using Eulerian tracers Full text
2012
Höglund, A. | Meier, H.E.M.
In recent years, the shipping of environmentally hazardous cargo has increased considerably in the Baltic proper. In this study, a large number of hypothetical oil spills with an idealized, passive tracer are simulated. From the tracer distributions, statistical measures are calculated to optimize the quantity of tracer from a spill that would stay at sea as long as possible. Increased time may permit action to be taken against the spill before the oil reaches environmentally vulnerable coastal zones. The statistical measures are used to calculate maritime routes with maximum probability that an oil spill will stay at sea as long as possible. Under these assumptions, ships should follow routes that are located south of Bornholm instead of the northern routes in use currently. Our results suggest that the location of the optimal maritime routes depends on the season, although interannual variability is too large to identify statistically significant changes.
Show more [+] Less [-]Occurrence and distribution of organochlorine residues in surface sediments of the Candarli Gulf (Eastern Aegean) Full text
2012
Pazi, Idil | Kucuksezgin, Filiz | Tolga Gonul, L.
The residual levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in surface sediments collected from Candarli Gulf. Total concentrations of OCPs and PCBs in sediments ranged from 10.2 to 57.3 and 2.8 to 205ngg⁻¹dwt, respectively. DDTs in sediments were derived from the aged and weathered agricultural soils in 61% of the sampling stations while 39% of the sites originated from the recent DDT inputs. Their concentrations appeared to be relatively low by global standards and only sediments receiving the impact from the Bakircay River and petrochemical industry approached the sediment quality guidelines for PCBs and DDTs. Based on ERL/ERM guidelines, DDT and PCBs posed ecological risk to the bottom-dwelling consumers.
Show more [+] Less [-]Multi-scale distribution and dynamics of bivalve larvae in a deep atoll lagoon (Ahe, French Polynesia) Full text
2012
Thomas, Y. | Garen, P. | Bennett, A. | Le Pennec, M. | Clavier, J.
Multi-scale distribution and dynamics of bivalve larvae in a deep atoll lagoon (Ahe, French Polynesia) Full text
2012
Thomas, Y. | Garen, P. | Bennett, A. | Le Pennec, M. | Clavier, J.
Bivalve larvae and hydrographic parameters were sampled over a range of spatio-temporal scales in a deep atoll lagoon. Bivalve larvae abundances were very high throughout the year: 18,550m⁻³ in average. Larvae were (i) concentrated at mid-depth with nocturnal ascent and diurnal descent, (ii) heterogeneously dispersed at the lagoon scale, (iii) subject to day-to-day variation in abundance and (iv) transferred between different parts of the lagoon providing evidence of intra-lagoonal connectivity. The primacy of physical factors was seen on large spatial scale with the diluting effect of water renewal and transfers by hydrodynamics. On smaller spatial scale, the primacy of biological processes was recognised, with larval swimming activity leading to dial vertical migration correlated with food concentration. Variations in larval abundance were driven by bivalve reproductive activity correlated with meteorological conditions (i.e. windy periods). Finally, relationship between bivalve larvae patterns and pearl oyster (Pinctada margaritifera) settlement structuring is discussed.
Show more [+] Less [-]Multi-scale distribution and dynamics of bivalve larvae in a deep atoll lagoon (Ahe, French Polynesia) Full text
2012
Thomas, Yoann | Garen, Pierre | Bennett, Auguste | Le Pennec, Marcel | Clavier, Jacques
Bivalve larvae and hydrographic parameters were sampled over a range of spatio-temporal scales in a deep atoll lagoon. Bivalve larvae abundances were very high throughout the year: 18,550 m(-3) in average. Larvae were (i) concentrated at mid-depth with nocturnal ascent and diurnal descent, (ii) heterogeneously dispersed at the lagoon scale, (iii) subject to day-to-day variation in abundance and (iv) transferred between different parts of the lagoon providing evidence of intra-lagoonal connectivity. The primacy of physical factors was seen on large spatial scale with the diluting effect of water renewal and transfers by hydrodynamics. On smaller spatial scale, the primacy of biological processes was recognised, with larval swimming activity leading to dial vertical migration correlated with food concentration. Variations in larval abundance were driven by bivalve reproductive activity correlated with meteorological conditions (i.e. windy periods). Finally, relationship between bivalve larvae patterns and pearl oyster (Pinctada margaritifera) settlement structuring is discussed. (C) 2012 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Prevalence and diversity of norovirus genogroups I and II in Hong Kong marine waters and detection by real-time PCR Full text
2012
Yang, Ning | Qi, Huizhou | Wong, Minnie Man Lai | Wu, Rudolf Shiu Sun | Kong, Richard Yuen Chong
Marine waters from six sites around Hong Kong with varying levels of sewage pollution were examined for noroviruses (NoVs) by PCR cloning and sequencing of a highly-variable N-terminal region of the VP1 capsid gene, at the ORF1-ORF2 junction of NoV. Phylogenetic analysis of genogroups GI- and GII-specific PCR clones obtained from different marine sites indicated that human NoV GI.1 and GII.4 strains are the most prevalent genotypes circulating in Hong Kong waters. GI- and GII-specific TaqMan-based real-time PCR assays targeting the ORF1-ORF2 junction of NoVs were used to quantify NoV particles in marine water samples in parallel with total Escherichia coli counts which were enumerated on TBX medium. No correlation of any significance between NoV and E. coli counts was observed which highlighted the inadequacy in using E. coli as a fecal indicator to predict the level of NoVs in marine waters to protect public health.
Show more [+] Less [-]Long-term monitoring of heavy metals in Chilean coastal sediments in the eastern South Pacific Ocean Full text
2012
Chandía, Cristian | Salamanca, Marco
Concentrations of seven metals (Al, Cd, Cu, Fe, Pb, Ni, Zn) were determined in 256 surface sediment samples, collected between May 2006 and November 2009, from 15 stations at the mouth of the Itata River and its adjacent marine zone (central-southern Chile) as part of an environmental monitoring program. The objectives of the work were to: (i) establish baseline metal concentrations in the sediments of the area and (ii) identify tendencies in the spatial and temporal distribution of the metals in these marine sediments. Concentrations were highest in the north zone of the Itata River mouth (stations E2C, E13C) for all the metals and at the stations farthest offshore from the mouth (E4, E6) for Cu, Fe, Pb, and Ni. The ranges in those concentrations were lower than those reported in other studies performed along the Chilean coast and lower than those observed in most other coastal systems around the world. Based on results of the indices used (geoaccumulation index, enrichment factor), the coastal sediments were not measurably elevated above natural levels.
Show more [+] Less [-]Anthropogenic “Litter” and macrophyte detritus in the deep Northern Gulf of Mexico Full text
2012
Wei, Chih-Lin | Rowe, Gilbert T. | Nunnally, Clifton C. | Wicksten, Mary K.
A deep-sea trawl survey of the Northern Gulf of Mexico has documented the abundance and diversity of human-generated litter and natural detrital plant material, from the outer margin of the continental shelf out to the Sigsbee abyssal plain. Plastics were the most frequently encountered type of material. Litter and debris were encountered more frequently in the eastern than in the western GoM. Land-derived plant material was located primarily within the head of the Mississippi Canyon, whereas ocean-derived plant material was spread evenly throughout the NE GoM. Human discards were principally from ships offshore. Some of the material was contained in metal cans that sank to the sea floor, probably in order to conform to international agreements that prohibit disposal of toxic material and plastics. The Mississippi Canyon was a focal point for litter, perhaps due to topography, currents or proximity to shipping lanes.
Show more [+] Less [-]Heavy metals contamination levels at the Coast of Aliağa (Turkey) ship recycling zone Full text
2012
Neşer, Gökdeniz | Kontas, Aynur | Ünsalan, Deniz | Uluturhan, Esin | Altay, Oya | Darılmaz, Enis | Küçüksezgin, Filiz | Tekoğul, Nermin | Yercan, Funda
Aliağa Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Concentrations of heavy metals and organic carbon in sediment of the Aliağa Bay were investigated to evaluate an environmental risk assessment from metals contamination in 2009–2010. Comparison of the metal concentrations with average shale and Mediterranean background levels revealed that most of the samples from the Aliağa were polluted with Hg, Cd, Pb, Cr, Cu, Zn, Mn and Ni. It was found that Hg, Pb, Cu, Zn and Ni levels in Aliağa Bay exceeded the PEL values. Sediments, contaminated with Pb, Cr, Cu, Zn and Ni were considered as heavily polluted per the SQG.
Show more [+] Less [-]An empirical model of water quality for use in rapid management strategy evaluation in Southeast Queensland, Australia Full text
2012
de la Mare, William | Ellis, Nick | Pascual, Ricardo | Tickell, Sharon
Simulation models have been widely adopted in fisheries for management strategy evaluation (MSE). However, in catchment management of water quality, MSE is hampered by the complexity of both decision space and the hydrological process models. Empirical models based on monitoring data provide a feasible alternative to process models; they run much faster and, by conditioning on data, they can simulate realistic responses to management actions. Using 10years of water quality indicators from Queensland, Australia, we built an empirical model suitable for rapid MSE that reproduces the water quality variables’ mean and covariance structure, adjusts the expected indicators through local management effects, and propagates effects downstream by capturing inter-site regression relationships. Empirical models enable managers to search the space of possible strategies using rapid assessment. They provide not only realistic responses in water quality indicators but also variability in those indicators, allowing managers to assess strategies in an uncertain world.
Show more [+] Less [-]Benthic recovery after fish farming cessation: A “beyond-BACI” approach Full text
2012
Aguado-Giménez, F. | Piedecausa, M.A. | Gutiérrez, J.M. | García-Charton, J.A. | Belmonte, A. | García-García, B.
The development of a benthic environment after fish-farming cessation was examined. To ascertain whether recovery occurred, several abiotic (granulometry, acid-volatile sulfides, total phosphorus and redox potential) and biotic (polychaete abundance) variables were monitored using a “beyond-BACI” approach. Before the cessation of farming, the geochemical conditions and polychaete assemblages differed among the impacted and control sites. After cessation, an improvement of the geochemical conditions was achieved. A significant tendency toward a recovery of the polychaete assemblage in the impacted area was observed, but significant differences still remained compared with the control sites. The acid-volatile sulfide level was responsible for these differences. The abundance of polychaete families associated with organically enriched sediments diminished at the impacted site after cessation, whereas the abundance of some sensitive and omnivorous families increased. The “beyond-BACI” approach provided a wider framework than other approaches, enabling us to differentiate the natural variability from those changes induced by the fish farm and farming cessation.
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