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Adsorption of trace metals to plastic resin pellets in the marine environment
2012
Holmes, Luke A. | Turner, Andrew | Thompson, Richard C.
Plastic production pellets collected from beaches of south west England contain variable concentrations of trace metals (Cr, Co, Ni, Cu, Zn, Cd and Pb) that, in some cases, exceed concentrations reported for local estuarine sediments. The rates and mechanisms by which metals associate with virgin and beached polyethylene pellets were studied by adding a cocktail of 5 μg L⁻¹ of trace metals to 10 g L⁻¹ pellet suspensions in filtered seawater. Kinetic profiles were modelled using a pseudo-first-order equation and yielded response times of less than about 100 h and equilibrium partition coefficients of up to about 225 ml g⁻¹ that were consistently higher for beached pellets than virgin pellets. Adsorption isotherms conformed to both the Langmuir and Freundlich equations and adsorption capacities were greater for beached pellets than for virgin pellets. Results suggest that plastics may represent an important vehicle for the transport of metals in the marine environment.
Показать больше [+] Меньше [-]Polycyclic aromatic hydrocarbons (PAHs) in continental shelf sediment of China: Implications for anthropogenic influences on coastal marine environment
2012
Liu, Liang-Ying | Wang, Ji-Zhong | Wei, Gao-Ling | Guan, Yu-Feng | Zeng, E. Y. (Eddy Y.)
Sediments collected from the continental shelf of China, embracing Yellow Sea, inner shelf of the East China Sea (ECS), and the South China Sea (SCS), were analyzed for polycyclic aromatic hydrocarbons (PAHs). The concentrations of anthropogenic PAHs (Σ₁₈PAH) were 27–224 ng/g dry weight, with an average of 82 ng/g. Sedimentary PAHs in the continental shelf off China were mainly derived from mixed residues of biomass, coal, and petroleum combustion. Fluvial transport and atmospheric deposition mainly accounted for sediment PAHs in the ECS inner shelf and Yellow Sea (and the SCS), respectively. Furthermore, statistically higher levels of Σ₁₈PAH (28–224 ng/g; mean 110 ng/g) in the Yellow Sea sediment than in the SCS sediment (28–109 ng/g; mean 58 ng/g) were probably resulted from higher PAH emissions from coke industry and domestic coal combustion in North China than in South China.
Показать больше [+] Меньше [-]Razorbills (Alca torda) as bioindicators of mercury pollution in the southwestern Mediterranean
2012
Espín, Silvia | Martínez-López, Emma | Gómez-Ramírez, Pilar | María-Mojica, Pedro | García-Fernández, Antonio J.
Levels of mercury (Hg) were analyzed in the tissues of 50 Razorbills (Alca torda), from the Mediterranean area, which had drowned in fishing nets. The mercury distribution pattern in tissues was similar to those of other studies (liver>feather vane>kidney>muscle>brain>feather shaft), with mercury concentrations of 2.85±0.90, 2.66±1.60, 2.23±0.87, 1.54±0.54, 1.48±0.54 and 1.30±0.76mg/kg (dry weight), respectively. It could be considered that Razorbills in the southwestern Mediterranean were chronically exposed to relatively low levels of MeHg, probably below 0.5ppm, via dietary intake. We have proposed prediction equations for brain and kidney Hg concentrations using feather shafts as non-invasive samples. This work provides a solid understanding of Razorbill Hg exposure both in their wintering and breeding grounds, and shows that this species can be useful for assessing marine environmental health in the Mediterranean area.
Показать больше [+] Меньше [-]Monitoring temporal and spatial trends of legacy and emerging contaminants in marine environment: Results from the environmental specimen bank (es-BANK) of Ehime University, Japan
2012
Tanabe, Shinsuke | Ramu, Karri
The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook.
Показать больше [+] Меньше [-]Influence of strong monsoon winds on the water quality around a marine cage-culture zone in a shallow and semi-enclosed bay in Taiwan
2012
Huang, Yuan-Chao Angelo | Huang, Shou-Chung | Meng, Pei-Jie | Hsieh, Hernyi Justin | Chen, Chaolun Allen
Influences of marine cage culture and monsoonal disturbances, northeasterly (NE) and southwesterly (SW) monsoons on the proximal marine environment were investigated across a gradient of sites in a semi-enclosed bay, Magong Bay (Penghu Islands, Taiwan). Elevated levels of ammonia produced by the cages were the main pollutant and distinguished the cage-culture and intermediary zones (1000m away from the cages) from the reference zone in the NE monsoon, indicating currents produced by the strong monsoon may have extended the spread of nutrient-enriched waters without necessarily flushing such effluents outside Magong Bay. Moreover, the levels of chlorophyll-a, dissolved oxygen, and turbidity were distinguishable between two seasons, suggesting that resuspension caused by the NE monsoon winds may also influence the water quality across this bay. It indicated that the impacts of marine cage culture vary as a function of distance, and also in response to seasonal movements of water driven by local climatic occurrences.
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2012
Chen, Hong | Zhang, Can | Yu, Yixuan | Han, Jianbo
Sorption of anionic perfluorooctane sulfonate (PFOS) on marine sediment was investigated in detail. It was found that solution ionic composition and sediment-specific parameters played important roles in affecting the sorption of PFOS. The results indicated that sorption of PFOS in seawater to marine sediments was strong (∼10 times higher than that in freshwater) and nonlinear (Freundlich nF values of 0.77–0.96). The sorption affinity was well correlated with sediment organic carbon content, indicating the importance of hydrophobic interactions. At a PFOS aqueous concentration of 10μg/L, PFOS distribution coefficients increased with the increasing salinity in solution, with an average rate of 0.48±0.03log units per a log unit of salinity. Further studies demonstrated that among common ions contributing to the salinity in seawater, dissolved calcium and magnesium are dominantly responsible for the sorption-enhancing effect of salinity for PFOS. This work will aid in better understanding of PFOS sorption mechanisms, and be useful for fate modeling of this class of contaminants in the marine environment.
Показать больше [+] Меньше [-]A strategy for detecting derelict fishing gear at sea
2012
McElwee, Kris | Donohue, Mary J. | Courtney, Catherine A. | Morishige, Carey | Rivera-Vicente, Ariel
Derelict fishing gear (DFG) is a highly persistent form of marine pollution known to cause environmental and economic damage. At-sea detection of DFG would support pelagic removal of this gear to prevent and minimize impacts on marine environments and species. In 2008, experts in marine debris, oceanography, remote sensing, and marine policy outlined a strategy to develop the capability to detect and ultimately remove DFG from the open ocean. The strategy includes three interrelated components: understanding the characteristics of the targeted DFG, indirectly detecting DFG by modeling likely locations, and directly detecting pelagic DFG using remote sensing. Together, these components aim to refine the search area, increase the likelihood of detection, and decrease mitigation response time, thereby providing guidance for removal operations. Here, we present this at-sea detection strategy, relate it to relevant extant research and technology, and identify gaps that currently prevent successful at-sea detection and removal of DFG.
Показать больше [+] Меньше [-]Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data
2012
Merchant, Nathan D. | Witt, Matthew J. | Blondel, Philippe | Godley, Brendan J. | Smith, George H.
Underwater noise from shipping is a growing presence throughout the world’s oceans, and may be subjecting marine fauna to chronic noise exposure with potentially severe long-term consequences. The coincidence of dense shipping activity and sensitive marine ecosystems in coastal environments is of particular concern, and noise assessment methodologies which describe the high temporal variability of sound exposure in these areas are needed. We present a method of characterising sound exposure from shipping using continuous passive acoustic monitoring combined with Automatic Identification System (AIS) shipping data. The method is applied to data recorded in Falmouth Bay, UK. Absolute and relative levels of intermittent ship noise contributions to the 24-h sound exposure level are determined using an adaptive threshold, and the spatial distribution of potential ship sources is then analysed using AIS data. This technique can be used to prioritise shipping noise mitigation strategies in coastal marine environments.
Показать больше [+] Меньше [-]Marine biosecurity: The importance of awareness, support and cooperation in managing a successful incursion response
2012
Piola, Richard F. | McDonald, Justin I.
Shipping is almost certainly the most prevalent human-mediated transport vector for non-indigenous species (NIS) within the marine environment. The Royal Australian Navy (RAN) has long acknowledged the importance of sound environmental management and in recent years has taken a proactive approach to addressing risks associated with marine biosecurity. primarily as a result of biofouling on Navy vessel returning from overseas operations. This paper describes two case studies that highlight the effectiveness of the RAN marine biosecurity management framework in identifying an unwanted marine species on Navy vessels, and the successful biosecurity management program that ensued. In particular, the early detection and identification of a suspect NIS, the quick response to the discovery and the collaborative approach adopted between the RAN and the Government regulatory agency (Western Australian Department of Fisheries) charged with coordinating the incursion response serves as a model for how future incursion responses should be reported and managed.
Показать больше [+] Меньше [-]Use of species sensitivity distributions to predict no-effect concentrations of an antifouling biocide, pyridine triphenylborane, for marine organisms
2012
Mochida, Kazuhiko | Onduka, Toshimitsu | Amano, Haruna | Ito, Mana | Ito, Katsutoshi | Tanaka, Hiroyuki | Fujii, Kazunori
We used species sensitivity distributions (SSDs) and a Bayesian statistical model to carry out a primary risk assessment for pyridine triphenylborane (PTPB) in Hiroshima Bay, Japan. We used SSDs derived from toxicity values, such as EC₅₀ and LC₅₀, obtained from this study and previous work to calculate hazardous concentrations that should protect 95% and 99% of species (HC₅ and HC₁) and demonstrated that the medians of the HC₅ and HC₁ were 0.78 and 0.17μg/L, respectively. We also used liquid chromatography/mass spectrometry to investigate the occurrence of PTPB in seawater from several coastal sites of Hiroshima Bay and detected PTPB at concentrations of 4.8–21pg/L. Comparison of environmental concentrations to the HC values suggests that the current ecological risk posed by PTPB in Hiroshima Bay is low. This is the first report of the detection of PTPB in the natural marine environment.
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