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Depositional environment and geochemical response of mangrove sediments from creeks of northern Maharashtra coast, India
2013
Volvoikar, Samida P. | Nayak, G.N.
Present study provides results of trace metal distribution in mangrove sediment cores collected from macro-tidal Khonda and Dudh creeks of Northern Maharashtra coast, India. Most of the metals showed significant higher addition in Dudh creek (core DC) as compared to Khonda creek (core KC). However, Khonda creek sediments did show anthropogenic enrichment of Mn, Zn and Ni, while Dudh creek sediments showed anthropogenic enrichment of almost all the studied metals. Large difference in metal concentration between the two creeks was attributed to their proximity to industries. The higher Mn, Zn and Ni content in Khonda creek was mainly attributed to addition from domestic and agricultural wastes. While high deterioration of Dudh creek sediments was the outcome of addition from industrial effluents.
Afficher plus [+] Moins [-]Difficulties in obtaining representative samples for compliance with the Ballast Water Management Convention
2013
Carney, Katharine J. | Basurko, Oihane C. | Pazouki, Kayvan | Marsham, Sara | Delany, Jane E. | Desai, D.V. | Anil, A.C. | Mesbahi, Ehsan
As implementation of the Ballast Water Convention draws nearer a major challenge is the development of protocols which accurately assess compliance with the D-2 Standard. Many factors affect the accuracy of assessment: e.g. large volume of ballast water, the shape, size and number of ballast tanks and the heterogeneous distribution of organisms within tanks. These factors hinder efforts to obtain samples that truly represent the total ballast water onboard a vessel.A known cell density of Tetraselmis suecica was added to a storage tank and sampled at discharge. The factors holding period, initial cell density and sampling interval affected representativeness. Most samples underestimated cell density, and some tanks with an initial cell density of 100cellsml−1 showed <10cellsml−1 at discharge, i.e. met the D-2 standard. This highlights difficulties in achieving sample representativeness and when applied to a real ballast tank this will be much harder to achieve.
Afficher plus [+] Moins [-]Environmental genotoxicity and cytotoxicity levels in fish from the North Sea offshore region and Atlantic coastal waters
2013
Baršienė, Janina | Rybakovas, Aleksandras | Lang, Thomas | Andreikėnaitė, Laura | Michailovas, Aleksandras
In the framework of the ICON project, environmental genotoxicity and cytotoxicity levels were assessed in blood erythrocytes of dab (Limanda limanda) and haddock (Melanogrammus aeglefinus) collected at 25 stations in the North Sea and near the coast of Iceland in August–October 2008. Micronuclei, nuclear buds and bi-nucleated cells with nucleoplasmic bridges were assessed as environmental genotoxicity biomarkers, and the frequency of fragmented-apoptotic and bi-nucleated erythrocytes were assessed as environmental cytotoxicity biomarkers. The lowest frequencies of genotoxic and cytotoxic abnormalities were detected in fish from the Icelandic study stations. The highest frequencies of abnormalities were recorded in dab from the Dogger Bank and the German Bight, in haddock from the Egersund Bank and from an area off the Firth of Forth (North Sea). In fish from the Icelandic reference area, frequencies of genotoxicity and cytotoxicity responses were significantly lower than in fish from most areas of the North Sea.
Afficher plus [+] Moins [-]Baseline of the butyltin distribution in surface sediments (0–20cm) of the Elbe estuary (Germany, 2011)
2013
Wetzel, Markus A. | Winterscheid, Axel | Wahrendorf, Dierk-Steffen
The concentrations of the butyltin (BT) species tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) were measured in the surface sediments (0–20cm) at 29 sites of the Elbe estuary in 2011. TBT values ranged from ‘undetectable’ to 41ngSng−1 dry weight (d.w.) with the two highest values measured in the inner section of the estuary near the port of Hamburg (32 and 41ngSng−1 d.w.). TBT, DBT, and MBT showed significant decreases towards the estuarine mouth (Spearman’s rho −0.660, −0.685, and −0.583, respectively, p<0.001). The degradation of TBT, assessed by the BT degradation index (BDI), showed a rising trend from the port of Hamburg towards the mouth of the estuary, though not a significant one (Spearman’s correlation, p=0.066). Annual sedimentation rates did not show any significant correlations (Spearman’s correlation) to BT pollution or to the butyltin degradation index (BDI).
Afficher plus [+] Moins [-]Persistent organic pollutants in benthic and pelagic organisms off Adélie Land, Antarctica
2013
Goutte, A. | Chevreuil, M. | Alliot, F. | Chastel, O. | Cherel, Y. | Eléaume, M. | Massé, G.
The concentrations of polychlorinated biphenyls (PCB), hexachlorobenzene (HCB), pentachlorobenzene (PeCB) and polybrominated diphenylethers (PBDE) were described in benthic and pelagic species collected off Adélie Land, Antarctica. Strong differences were observed among species, with reduced PeCB and HCB levels in benthic species, and elevated PCB levels in the Antarctic yellowbelly rockcod, the Antarctic sea urchin and the snow petrel. Lower-chlorinated congeners were predominant in krill; penta-PCBs in benthic organisms; hexa- and hepta-PCBs in seabirds and cryopelagic fish. This segregation may result from sedimentation process, specific accumulation and excretion, and/or biotransformation processes. The presence of PBDEs in Antarctic coastal organisms may originate from atmospheric transport and partly from a contamination by local sources. Although POP levels in Antarctic marine organisms were substantially lower than in Arctic and temperate organisms, very little is known about their toxic effects on these cold-adapted species, with high degree of endemism.
Afficher plus [+] Moins [-]Looking at the aquatic contamination through fish eyes – A faithful picture based on metals burden
2013
Pereira, Patrícia | Raimundo, Joana | Canário, João | Almeida, Armando | Pacheco, Mario
This study describes for the first time metal accumulation in the eyes of native golden grey mullet (Liza aurata) coupled with water/sediment quality assessment. Sampling was performed in the Tagus estuary (Portugal) where a confined area (Barreiro) is severely contaminated by metal/loids. Levels of As, Cu, Pb, Hg and Cd in sediments from Barreiro were one order of magnitude higher than those from the reference site. Data on water column pointed also to a higher availability of Cu, Pb, Cd and Hg (including MeHg) at Barreiro. Accordingly, fish eyes accumulated higher levels of metal/loids at Barreiro than at the reference site. These findings support the use of fish eyes as a target organ in environmental health assessment since they reflect sediment and water contamination. It points also to the importance of evaluate eye changes at structural/functional levels in order to examine in what extent accumulated metals could compromise this perceptive system.
Afficher plus [+] Moins [-]Processing of fecal sludge to fertilizer pellets using a low-cost technology in Ghana
2013
Nikiema, Josiane | Cofie, Olufunke | Impraim, Robert | Adamtey, N.
This paper describes a study that was aimed at optimizing the pelletization of fecal sludge-based fertilizers for agricultural use. The process developed is easy to implement and increases the marketability of the products while also addressing a serious health and environmental challenge. The study took place during the period 2011-2012 in Ghana. The fecal sludge, rich in nutrients and organic matter, was dried and used to produce five different fertilizers (i.e., four formulations of compost and one with gamma irradiated material). Each material was then pelletized using locally constructed machinery. Key operating parameters, such as moisture content (10-55% in mass), binder type (clay or starch) and concentration (0-10% in mass), were varied and their impacts on the characteristics of pellets (e.g., amount of fine materials generated, length distribution or stability of pellets, and pellet disintegration rate) were also followed. Given the low analyzing capabilities of developing countries, some simple analytical methods were developed and used to compare pellets produced under different conditions. The results confirmed that the addition of 3% of pregelatinized starch is recommended during pelletization of fecal sludge-based fertilizers. Applicable moisture contents were also identified per fertilizer type, and were found to comprise between 21 and 43%.
Afficher plus [+] Moins [-]Ecology of the ciguatera causing dinoflagellates from the Northern Great Barrier Reef: Changes in community distribution and coastal eutrophication
2013
Skinner, Mark P. | Lewis, Richard J. | Morton, Steve
Ciguatera fish poisoning (CFP) is known to be caused by the ciguatoxins from the dinoflagellate genus Gambierdiscus, however, there is the potential for other toxins such as okadaic acid and dinophysistoxins from the genus Prorocentrum, and palytoxin from the genus Ostreopsis, to contaminate seafood. These genera may also be indicators of ecosystem health and potentially impact on coral reef ecosystems and the role they may play in the succession of coral to macroalgae dominated reefs has not been researched. Sixteen GBR field sites spanning inshore, mid-lagoon and outer lagoon (offshore) regions were studied. Samples were collected from September 2006 to December 2007 and abundance of benthic dinoflagellates on different host macroalgae and concentration of nutrients present in the water column were determined. The maximum abundance of Prorocentrum, Ostreopsis and Gambierdiscus found was 112, 793 and 50 cells per gram wet weight of host macroalgae, respectively. The average level of Dissolved Inorganic Nitrogen (DIN) in the water column across all sites (0.03mg/L) was found to be more than double the threshold critical value (0.013mg/L) for healthy coral reefs. Compared to a previous study 1984, there is evidence of a major shift in the distribution and abundance of these dinoflagellates. Inshore reefs have either of Prorocentrum (as at Green Island) or Ostreopsis (as at Magnetic Island) dominating the macroalgal surface niche which was once dominated by Gambierdiscus, whilst at offshore regions Gambierdiscus is still dominant. This succession may be linked to the ongoing eutrophication of the GBR lagoon and have consequences for the sources of toxins for ongoing cases of ciguatera.
Afficher plus [+] Moins [-]A probabilistic model estimating oil spill clean-up costs – A case study for the Gulf of Finland
2013
Montewka, Jakub | Weckström, Mia | Kujala, P.
Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs.In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement.We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA).
Afficher plus [+] Moins [-]Sublethal effects of a chlorinated and heated effluent on the physiology of the mussel, Mytilus edulis L.: A reduction in fitness for survival?
2013
(Krysia),
Coastal power stations entrain large volumes of cooling water, requiring biocidal treatment to prevent biological fouling. Discharged effluent is both heated and contaminated with residual traces of biocide and so it is necessary to quantify the impacts of this discharge. Cooling water from Heysham 2 nuclear power station, NW England, UK, is discharged to the intertidal area, via a culvert (to minimise erosion and maximise dilution and dispersion by directing the effluent into the receiving water at all states of the tide) within which the effluent is contained at low water. The culvert and surrounding coastal area support a population of blue mussels (Mytilus edulis). Mussel health was determined along a gradient of exposure, using three physiological indices: Scope for Growth, Gonad Mantle Index and Somatic Condition Index (K Factor). The Mussels within the culvert exhibited reduced physiological index values compared to an external site. A trend was identified down the length of the culvert, representing a gradient of exposure and indicating a potential negative effect on growth and reproductive output.
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