Persistence of yessotoxin under light and dark conditions     

Mitrovic SM  Hamilton B  McKenzie L  Furey A  James KJ 《Marine environmental research》2005,60(3):397-401

The change in concentration of the disulfated polyether yessotoxin (YTX) produced by a culture of the marine dinoflagellate Protoceratium reticulatum was measured in laboratory experiments under light and dark conditions. Experimental cultures were inoculated and grew at a growth rate of 0.14 d(-1) until stationary phase was reached, after approximately 21 days. Cultures were maintained in the stationary phase until 31 days after inoculation. Cells of P. reticulatum contained a concentration of approximately 10-15 pg YTX cell(-1) during stationary phase but this was considerably lower (<5 pg cell-1) during the growth phase. Low amounts of 45-hydroxy-YTX were also detected. At day 32, P. reticulatum was killed by cooling to 1 degrees C (confirmed microscopically) and YTX concentrations were measured periodically under light and dark conditions. YTX concentrations decreased rapidly to approximately 10% of the initial concentration within the first 3 days and depleted to near zero within a week in the light treatment. In the dark environment, YTX persisted longer with approximately 10% of the initial YTX concentration still remaining after 18 days.  相似文献   

Hepatic CYP1A levels and EROD activity in English sole: biomonitoring of marine contaminants in Vancouver Harbour   总被引：4，自引：0，他引：4  

Miller KA  Addison RF  Bandiera SM 《Marine environmental research》2004,57(1-2):37-54

To assess chemical contaminant stress in the marine environment, ethoxyresorufin-O-deethylase (EROD) activity and cytochrome P450 1A (CYP1A) expression were measured in 88 English Sole (Pleuronectes vetulus) collected during May and June 1999 from four sites in Vancouver Harbour and at an expected reference site outside the harbour. Hepatic microsomes were prepared from the fish and analyzed for total CYP content, EROD activity, and CYP1A protein levels. Hepatic EROD activity and CYP1A protein levels were elevated in fish from two sites in the inner harbour. A comparison with sediment chemistry data showed that fish with increased EROD activity and CYP1A levels came from sites containing relatively high levels of polycyclic aromatic hydrocarbons and polychlorinated biphenyls. Unexpectedly high levels of EROD activity and CYP1A protein were also found in fish from a reference site near Gibsons, in Howe Sound. The elevated EROD activity and CYP1A expression in fish from this site cannot be explained by the chemical analysis data collected.  相似文献   

Source and distribution of trace metals in the Medway and Swale estuaries, Kent, UK     

Spencer KL  MacLeod CL  Tuckett A  Johnson SM 《Marine pollution bulletin》2006,52(2):226-231

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A review and assessment of tributyltin contamination in the North Sea,based on surveys of butyltin tissue burdens and imposex/intersex in four species of neogastropods   总被引：4，自引：0，他引：4  

Birchenough AC  Barnes N  Evans SM  Hinz H  Krönke I  Moss C 《Marine pollution bulletin》2002,44(6):534-543

It is evident from measures of butyltin tissue burdens and imposex or intersex in neogastropods that tributyltin (TBT) contamination of coastal waters and open parts of the North Sea is now low. It has been declining for at least the past decade. This is probably due to two measures. First, regulations prohibiting the use of TBT-based paints on small boats and fish farms have reduced inputs of TBT from these sources so that they are now negligible (except possibly where the regulations are flaunted). Second, there is evidence from sites, where commercial vessels are the sole source of TBT, that the adoption of TBT SPC paints has been effective in reducing environmental levels of these contaminants. However, poor dockyard practices, allowing TBT-contaminated wastes, including paint flakes, to accumulate in sediments have left a legacy of hot-spots of contamination in some ports. The impact is localised so that TBT contamination is low in coastal areas immediately adjacent to ports.  相似文献   

Distribution of nickel in a polluted mangrove habitat of the Indus Delta     

Saifullah SM  Khan SH  Ismail S 《Marine pollution bulletin》2002,44(6):570-576

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98年水平定向钻进用地面步行式和孔底式轨迹测量系统回顾     

布依.  SM 冯起增 《岩土钻凿工程》1999,(2):163-166

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覆盖层中物质的电化学搬运：冰川地带选择性浸析地球化学异常形 …     

Hami.  SM  吴传芝 《国外地质勘探技术》1999,(5):14-26

最近的研究表明,在厚冰川覆盖层上方,存在着空间上与地下矿体有联系的地球化学异常。现存的模型只能解释薄覆盖层中的地球化学异常,对这类异常何以会在厚层且年轻的覆盖层中出现,则无法作出解释。此前还没有提出过能够解释厚覆盖层中地球化学异常的新模型。本文讨论了现存模型的一些问题,并提出一种新的解释 模型,认为电化学引发的物质搬 是厚冰川沉积层上方地化异常形成的原因。  相似文献   

The EU Directive on port reception facilities for ship-generated waste and cargo residues: the results of a second survey on the provision and uptake of facilities in North Sea ports     

Carpenter A  Macgill SM 《Marine pollution bulletin》2005,50(12):1541-1547

The aim of this paper is to evaluate the results of a survey of the availability and uptake of port reception facilities within the North Sea area. The evaluation is based primarily on original survey data from the autumn of 2002 which followed on from a similar survey conducted in the summer of 2000. The EU Directive on port reception facilities for ship-generated waste etc. (Directive 2000/59/EC) was due to enter into force in December 2002, and required all EU ports to provide reception facilities to meet the needs of the vessels normally calling in at them. This paper examines the readiness of North Sea ports to meet that requirement and also considers the actual uptake levels of facilities, where ports were able to provide such information.  相似文献   

Associations of Vertebrate Skeletal Concentrations and Discontinuity Surfaces in Terrestrial and Shallow Marine Records: A Test in the Cretaceous of Montana     

Rogers RR  Kidwell SM 《The Journal of geology》2000,108(2):131-154

Although lags of bones and teeth are commonly cited criteria for marine unconformities, the consistency of the association of vertebrate fossils and discontinuity surfaces, as well as the taphonomic (postmortem) controls on this relationship, are poorly understood. A field test across fluvial, paralic, and shallow marine facies in the Campanian Two Medicine and Judith River formations of Montana indicates that the distribution of vertebrate skeletal concentrations is poorly correlated with the inferred durations of erosional and omissional hiatuses. Instead, vertebrate concentrations associated with discontinuities of all durations tend to be patchy and closely track the abundance of fossil material in underlying and lateral facies. Based on the analysis of 83 measured sections, we found first that erosional bases of channels and minor scours within channels yield vertebrate lags; tidally influenced fluvial deposits are more productive than are "upland" fluvial deposits. Second, erosional shoreface ravinements and their correlative transgressive marine flooding surfaces (fourth-order sequence boundaries) have well-developed vertebrate lags only along segments that cut across older shoreface deposits. Third, a nonerosional, widely traceable discontinuity, which is interpreted as the nonmarine extension of a 75.4-Ma third-order transgressive surface, is completely lacking in vertebrate concentrations. Despite being unfossiliferous itself, this discontinuity does mark a regional change in the richness of the vertebrate fossil record, with overlying beds characterized by a much greater abundance of skeletal material. Fourth, a laterally extensive set of erosional surfaces, embedded within multistory fluvial sandstone sheets, is the nonmarine extension of an 80-Ma third-order sequence boundary in the marine basin and lacks vertebrate concentrations. The strong dependence of vertebrate lag development on preexisting local sources of skeletal material rather than on the magnitude of the erosional vacuity or the duration of the hiatus contrasts with skeletal concentrations of invertebrates in marine successions, where exhumation is generally much less important than the production of new elements during the hiatus. These findings provide a guide to prospecting productive fossil horizons in terrestrial records and underscore fundamental differences in the ways in which bioclastic material accumulates in terrestrial and shallow marine settings, the qualities of paleobiologic data derived from such concentrations, and the relative reliabilities of skeletal material as cues to stratigraphically significant discontinuities.  相似文献   

Modelling the biological half-life and seasonality of ¹⁴C in Fucus vesiculosus from the east coast of Ireland: implications for the estimation of future trends     

Keogh SM  Cournane S  León Vintró L  McGee EJ  Mitchell PI 《Marine pollution bulletin》2011,62(4):696-700

Radiocarbon levels were recorded in Fucus vesiculosus samples collected on a monthly basis over a three-year period at a site on the east coast of Ireland. The resulting data was analysed using a numerical model which estimates the transit times from the Sellafield plant to the sampling location, and the mean availability time of ¹⁴C in seaweed. With the inclusion of a model parameter allowing for seasonal variability in uptake by the Fucus, good correlation was observed between the predicted and measured concentrations. Future temporal trends of ¹⁴C Fucus concentrations along the eastern Irish coastline were modelled with the application of three possible prospective discharge scenarios, predicting ¹⁴C Fucus concentrations to reduce to ambient background levels within 2.5-years of discharges being set to zero. Such projections may prove helpful in assessing the consequences of discharge management and policy making in the context of the OSPAR convention.  相似文献