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Evaluation for the ecological quality status of coastal waters in East China Sea using fuzzy integrated assessment method Full text
2012
Wu, H.Y. | Chen, K.L. | Chen, Z.H. | Chen, Q.H. | Qiu, Y.P. | Wu, J.C. | Zhang, J.F.
This research presented an evaluation for the ecological quality status (EcoQS) of three semi-enclosed coastal areas using fuzzy integrated assessment method (FIAM). With this method, the hierarchy structure was clarified by an index system of 11 indicators selected from biotic elements and physicochemical elements, and the weight vector of index system was calculated with Delphi-Analytic Hierarchy Process (AHP) procedure. Then, the FIAM was used to achieve an EcoQS assessment. As a result of assessment, most of the sampling stations demonstrated a clear gradient in EcoQS, ranging from high to poor status. Among the four statuses, high and good, owning a ratio of 55.9% and 26.5%, respectively, were two dominant statuses for three bays, especially for Sansha Bay and Luoyuan Bay. The assessment results were found consistent with the pressure information and parameters obtained at most stations. In addition, the sources of uncertainty in classification of EcoQS were also discussed.
Show more [+] Less [-]The geography of mercury and PCBs in North Carolina’s local seafood Full text
2012
Freitag, Amy | Sohn, Nari | Hooper, Mark | Rittschof, Dan
Mercury and PCBs are used by non-governmental organizations and federal agencies to inform seafood safety recommendations. Pollution dynamics suggest recommendations on the national scale may be too large to be accurate. We tested softshell and hardshell blue crab, white and pink shrimp, oysters, clams, spot, and mullet from fishers in each of the three North Carolina fishery districts. We measured mercury using EPA method 7473 and PCBs using a commercially available ELISA kit. Over 97% of samples were below the Environmental Protection Agency levels of concern for both mercury and PCBs. Mercury and PCBs have different spatial dynamics, but both differ significantly by water body, suggesting that seafood safety recommendations should occur by water body instead of at the national scale. This finding supports previous research suggesting that differences in water chemistry, terrestrial influence, and flushing time in a particular water body control the contaminant load in locally resident species.
Show more [+] Less [-]Isolation and characterization of crude-oil-degrading bacteria from the Persian Gulf and the Caspian Sea Full text
2012
Hassanshahian, Mehdi | Emtiazi, Giti | Cappello, Simone
Twenty-five crude-oil-degrading bacteria were isolated from oil-contaminated sites in the Persian Gulf and the Caspian Sea. Based on a high growth rate on crude oil and on hydrocarbon degradation ability, 11 strains were selected from the 25 isolated strains for further study. Determination of the nucleotide sequence of the 16S rRNA gene showed that these isolated strains belonged to genera Acinetobacter, Pseudomonas, Gordonia, Rhodococcus, Cobetia, Halomonas, Alcanivorax, Marinobacter and Microbacterium. Among the 11 isolates, strains BS (Acinetobacter calcoaceticus, 98%) and PG-12 (Alcanivorax dieselolei, 98%) were the most effective in degrading crude oil. Rate of crude-oil degradation of 82% (isolate BS) and 71% (isolate PG-12) were observed after 1week of cultivation in mineral medium. These strains had high emulsification activity and biosurfactant production. GC–MS analysis showed that A. dieselolei PG-12 can degrade different alkanes in crude oil. Screening of the distribution of the alkane hydroxylase gene in 25 isolates in relation to the source of isolation indicated that the group (II) alkane hydroxylase is prevalent in the Caspian Sea, but in the Persian Gulf, the frequency of the group (III) alkane hydroxylase gene is greater than that of the group (II) alkane hydroxylase gene.
Show more [+] Less [-]Monitoring of East Channel dredge areas benthic fish population and its implications Full text
2012
Drabble, Ray
Regional annual sampling of commercial fish stocks formed a high priority for monitoring studies attendant with the granting of aggregate dredging licenses in the Eastern Channel Region (ECR) which had previously not been dredged. An assessment of 4m beam trawl sampling between 2005 and 2008 following the granting of licences in 2006 is provided. The majority of fish species have shown marked reductions in abundance since commencement of dredging. Draghead entrainment has been identified as a possible contributory cause based upon the known vulnerability of selected species (Drabble, 2012). Other environmental factors considered offer no explanation for the changes in abundance. Comparative analyses with ICES data for plaice and sole over the study period demonstrate that changes in the ECR do not result from seasonal flux in the wider populations. An alternative impact model and potential mitigation measures are suggested.
Show more [+] Less [-]Organotin compounds in seawater and Mytilus galloprovincialis mussels along the Croatian Adriatic Coast Full text
2012
Furdek, Martina | Vahčič, Mitja | Ščančar, Janez | Milačič, Radmila | Kniewald, Goran | Mikac, Nevenka
In this work, data on the level of organotin compounds (OTCs) in seawater and mussels collected along the entire Croatian Adriatic Coast are presented. The samples were collected in 2009 and 2010 at 48 locations representing different levels of maritime activities, including marinas, ports and reference sites. Butyltins (BuTs) were found in all analyzed samples, representing >97% of OTCs, and ranged from 0.46 to 27.98ngSnL⁻¹ in seawater and from <6 to 1675ngSng⁻¹ in mussels. The results indicate a recent input of TBT, with the highest concentrations of BuTs found in the marinas. It appears that the Adriatic coast is still polluted with TBT despite the fact that TBT-containing antifouling paints have been banned in Croatia since 2008. It is questionable how much TBT pollution decreased since 2005, when a high incidence of imposex was established in the same area.
Show more [+] Less [-]Organotin levels in Nazaré canyon (west Iberian Margin, NE Atlantic) and adjacent coastal area Full text
2012
Sousa, Ana C.A. | Oliveira, Isabel B. | Laranjeiro, Filipe | Takahashi, Shin | Tanabe, Shinsuke | Cunha, Marina R. | Barroso, Carlos M.
Organotin compounds (OTs) are ubiquitous in the marine environment and high concentrations (μgg⁻¹ range) in sediments from different coastal areas around the world have been reported. However, few reports have described the OTs contamination status in the offshore and deep sea environment. This work investigated organotin levels in Nazaré canyon for the first time. Levels of monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), diphenyltin (DPT), triphenyltin (TPT), dioctyltin (DOT) and trioctyltin (TOT) were quantified in sediment samples from the upper flanks of the canyon and from the adjacent coastal area. TBT levels detected in the canyon flanks are about two to three orders of magnitude lower than those found in the coastal area. Nevertheless, when quantifiable, TBT levels in the canyon samples were higher than the Environmental Assessment Criteria set for TBT in sediments by the OSPAR Commission indicating that at those locations negative ecological impacts are likely to occur.
Show more [+] Less [-]Links between bacterial communities in marine sediments and trace metal geochemistry as measured by in situ DET/DGT approaches Full text
2012
Gillan, David C. | Baeyens, Willy | Bechara, Rafeh | Billon, Gabriel | Denis, Kevin | Grosjean, Philippe | Leermakers, Martine | Lesven, Ludovic | Pede, Annelies | Sabbe, Koen | Gao, Yue
Our current view about the relationship between metals and bacteria in marine sediments might be biased because most studies only use ex situ approaches to quantify metals. The aim of the present research was to compare ex situ and in situ methods of metal measurement (DET and DGT – diffusive equilibration or diffusive gradients in thin-films) and relate the results with two commonly used microbiological variables (bacterial biomass and bacterial diversity as revealed by DGGE). No previous studies have used such in situ approaches in microbial ecology. For biomass and most of the investigated trace metals (Ag, Cd, Sn, Cr, Ni, Cu, Pb, and Al) no significant correlations were found. The exceptions were Fe, Mn, Co, and As which behave like micronutrients. For bacterial diversity, no relevant relationships were found. We conclude that in situ methods are more adapted tools for microbial ecologists but that ex situ approaches are still necessary.
Show more [+] Less [-]Fine sediment and nutrient dynamics related to particle size and floc formation in a Burdekin River flood plume, Australia Full text
2012
Bainbridge, Zoe T. | Wolanski, Eric | Álvarez-Romero, Jorge G. | Lewis, Stephen E. | Brodie, J. E. (Jon E.)
The extreme 2010–2011 wet season resulted in highly elevated Burdekin River discharge into the Great Barrier Reef lagoon for a period of 200days, resulting in a large flood plume extending >50km offshore and >100km north during peak conditions. Export of suspended sediment was dominated by clay and fine silt fractions and most sediment initially settled within ∼10km of the river mouth. Biologically-mediated flocculation of these particles enhanced deposition in the initial low salinity zone. Fine silt and clay particles and nutrients remaining in suspension, were carried as far as 100km northward from the mouth, binding with planktonic and transparent exopolymer particulate matter to form large floc aggregates (muddy marine snow). These aggregates, due to their sticky nature, likely pose a risk to benthic organisms e.g. coral and seagrass through smothering, and also by contributing to increased turbidity during wind-induced resuspension events.
Show more [+] Less [-]The oil spill model OILTRANS and its application to the Celtic Sea Full text
2012
Berry, Alan | Dąbrowski, Tomasz | Lyons, Kieran
The oil spill model OILTRANS and its application to the Celtic Sea Full text
2012
Berry, Alan | Dąbrowski, Tomasz | Lyons, Kieran
This paper describes details of an oil spill model, OILTRANS, developed by the authors. The model is an off-line particle-transport model coupled to the most up to date operational met-ocean model forecasts. Formulations for the dominant oil fate processes of spreading, advection, diffusion, evaporation, emulsification and dispersion have been encoded, providing the model with the ability to accurately predict the horizontal movement of surface oil slick, the vertical entrainment of oil into the water column and the mass balance of spilled oil. The application of the OILTRANS model to an accidental release during a ship-to-ship fuel transfer in the Celtic Sea in February 2009 is presented to validate the system. Comparisons with aerial observations of the oil slick at the time of the incident, and subsequent model simulations, indicate that the OILTRANS model is capable of accurately predicting the transport and fate of the oil slick.
Show more [+] Less [-]The oil spill model OILTRANS and its application to the Celtic Sea Full text
2012
Berry, Alan | Dabrowski, Tomasz | Lyons, Kieran
NOTICE: this is the author’s version of a work that was accepted for publication in Marine Pollution Bulletin. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Marine Pollution Bulletin, [Volume 64, Issue 11, (November 2012)] doi:10.1016/j.marpolbul.2012.07.036 | This paper describes details of an oil spill model, OILTRANS, developed by the authors. The model is an off-line particle-transport model coupled to the most up to date operational met-ocean model forecasts. Formulations for the dominant oil fate processes of spreading, advection, diffusion,evaporation, emulsification and dispersion have been encoded, providing the model with the ability to accurately predict the horizontal movement of surface oil slick, the vertical entrainment of oil into the water column and the mass balance of spilled oil. The application of the OILTRANS modelto an accidental release during a ship-to-ship fuel transfer in the Celtic Sea in February 2009 is presented to validate the system. Comparisons with aerial observations of the oil slick at the time ofthe incident, and subsequent model simulations, indicate that the OILTRANS model is capable of accurately predicting the transport and fate of the oil slick.
Show more [+] Less [-]Spatial distribution and source apportionment of PAHs in surficial sediments of the Yangtze Estuary, China Full text
2012
Li, Baohua | Feng, Chenghong | Li, Xue | Chen, Yaxin | Niu, Junfeng | Shen, Zhenyao
Spatial distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the Yangtze Estuary, especially the North Branch, have been fully investigated. PAH concentrations increased with the descending distance from the inner estuary to the adjacent sea, and varied significantly in various estuarine regions. Water currents (e.g., river runoff and ocean current) greatly affected the distribution pattern. In addition, ambient sewage and traffic also contributed to the PAH pollution in the estuary. In the adjacent sea, PAH values along the −20m isobath were higher than those along the −10m isobath due to the “marginal filter” phenomenon formed by different water currents. In most sites, PAHs had poor correlations with sediment size, but had positive correlations with total organic carbon. Based on the qualitative and quantitative analysis results, PAH sources were proved to be mainly from a mixture of petroleum combustion, biomass, and coal combustion.
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