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Activity levels of 210Po and 210Pb in some fish species of the Izmir Bay (Aegean Sea)
2013
Aközcan, S. | Uğur, A.
Concentrations of 210Po and 210Pb were determined in the edible muscle tissue of twelve species of marine fish collected from Izmir Bay in the Aegean Sea Region of Turkey during the 2006–2007. 210Po activity concentrations in fish samples were found to vary from ND to 400±9Bqkg−1 dry weight and 210Pb activity concentrations were found to vary from ND to 15±3Bqkg−1 dry weight. The highest dose contribution due to 210Po to humans was found to be 8.908μSvy−1.
Показать больше [+] Меньше [-]First record of sea snake (Hydrophis elegans, Hydrophiinae) entrapped in marine debris
2013
Udyawer, Vinay | Read, Mark A. | Hamann, Mark | Simpfendorfer, Colin A. | Heupel, Michelle R.
Entanglement in derelict fishing gear and other marine debris is a major threat to the survival of large marine wildlife like cetaceans, seabirds and sea turtles. However, no previous reports of entanglement or entrapment have been recorded in sea snakes (Hydrophiinae). We report here on a sea snake (Hydrophis elegans) found with a ceramic washer encircling its body captured from the north-east coast of Queensland, Australia. The ring had constricted the body and over time caused extensive damage to the underlying tissues. A post-mortem examination showed the snake was severely emaciated as the ring restricted the passage of food to the stomach and intestine. This is the first record of mortality due to marine debris entrapment in sea snakes.
Показать больше [+] Меньше [-]Link between sewage-derived nitrogen pollution and coral disease severity in Guam
2013
Redding, Jamey E. | Myers-Miller, Roxanna L. | Baker, David M. | Fogel, Marilyn | Raymundo, Laurie J. | Kim, Kiho
The goals of this study were to evaluate the contribution of sewage-derived N to reef flat communities in Guam and to assess the impact of N inputs on coral disease. We used stable isotope analysis of macroalgae and a soft coral, sampled bimonthly, as a proxy for N dynamics, and surveyed Porites spp., a dominant coral taxon on Guam’s reefs, for white syndrome disease severity. Results showed a strong influence of sewage-derived N in nearshore waters, with δ15N values varying as a function of species sampled, site, and sampling date. Increases in sewage-derived N correlated significantly with increases in the severity of disease among Porites spp., with δ15N values accounting for more than 48% of the variation in changes in disease severity. The anticipated military realignment and related population increase in Guam are expected to lead to increased white syndrome infections and other coral diseases.
Показать больше [+] Меньше [-]Temporal trends in dioxins (polychlorinated dibenzo-p-dioxin and dibenzofurans) and dioxin-like polychlorinated biphenyls in Baltic herring (Clupea harengus)
2013
Miller, Aroha | Hedman, Jenny E. | Nyberg, Elisabeth | Haglund, Peter | Cousins, Ian T. | Wiberg, Karin | Bignert, Anders
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyl (dl-PCBs) concentrations in Baltic herring (Clupea harengus) have been relatively stable since the mid to late 1990s. It is unclear why concentrations in Baltic herring are not following the observed decreases in other environmental matrices. Here, changes in long-term temporal trends in Baltic herring were examined. A number of biological variables were examined alongside the temporal trends to investigate whether fish biology e.g., growth (length, weight, age), lipid content, reproductive phase or fishing date may provide an explanation for the temporal trends observed.Significant (p<0.05) decreasing trends were observed for PCDD/F toxic equivalents (TEQPCDD/F) at three of the four sites (lipid weight (lw) and wet weight (ww), Swedish west coast lw only); however, other TEQ values e.g., TEQPCDD, TEQPCDF, TEQdl-PCB, TEQPCDD/F+dl-PCB were inconsistent, decreasing at some sites but not others. In the most recent 10years of data, fewer significant decreases were seen overall. Over the examined time period, significant decreases (Bothnian Bay, p<0.01, southern Baltic Proper, p<0.02) and increases (Swedish west coast, p<0.02) in lipid content, growth dilution or lack thereof, and significant changes in age were observed. However herring were not randomly selected which biases this result. Continual efforts to decrease PCDD/F and dl-PCB emissions and to locate/reduce hotspots are necessary, while bearing in mind that herring biology may be impeding faster decreases of these chemicals.
Показать больше [+] Меньше [-]Relationship between wind and seagrass meadows in a non-tidal eutrophic lagoon studied by a Wave Exposure Model (WEMo)
2013
Rubegni, Fabrizio | Franchi, Enrica | Lenzi, Mauro
The hydrodynamic action of wind and the distribution of biomass of seagrass meadows in a non-tidal eutrophic lagoon (Orbetello Lagoon, Tuscany, Italy) were analysed for correlations by simulation with a Wave Exposure Model (WEMo) on 5-year data series. WEMo and statistical analysis established a weak direct correlation between the areas that the model identified as being subject to resuspension and transport of sediment and those actually colonised by seagrass. A significant difference was found between surface and bottom hydrodynamics. The areas that the model identified as exposed to higher energy surface hydrodynamics proved to be inversely correlated with seagrass biomass. Multivariate statistical analysis ordered the model variables according to their relative importance. The model indicated the need for further study, demonstrating its utility for environmental management of eutrophic lagoons.
Показать больше [+] Меньше [-]Initial impacts of the Hebei Spirit oil spill on the sandy beach macrobenthic community west coast of Korea
2013
Yu, Ok Hwan | Lee, Hyung-Gon | Shim, Won Joon | Kim, Moonkoo | Park, Heung-Sik
Petroleum hydrocarbon contamination and macrobenthos in the sandy tidal flats of Taean were monitored for 1year to assess the impacts of Hebei Spirit oil on the macrobenthic community. A total of 207 macrobenthic fauna was collected, and the mean density and biomass of macrobenthic fauna continued to decrease until 12months after the oil spill, but macrobenthic density at the most heavily affected sites increased by about twofold. In January 2008, the dominant species occurred at very low densities in strongly affected sites. The macrobenthic communities differed between oil-affected and unaffected sites. In particular, differences in community structure at Mallipo beach were larger than those at Shinduri. We suggest that long-term monitoring is needed to assess the specific effects of oil pollution on the sandy intertidal macrobenthic community.
Показать больше [+] Меньше [-]Perfluorinated compounds in blood of Caretta caretta from the Mediterranean Sea
2013
Guerranti, Cristiana | Ancora, Stefania | Bianchi, Nicola | Perra, Guido | Fanello, Emiliano Leonida | Corsolini, Simonetta | Fossi, Maria Cristina | Focardi, Silvano Ettore
Perfluorinated compounds (PFCs), widely used for their hydro-oil repellent properties, are almost non-degradable in the environment; there is scientific evidence that indicate bioaccumulation. They represent a threat to many organisms, because they are toxic and are endocrine disruptors. Scientific studies have demonstrated the presence of PFCs in blood and liver samples of fish, turtles, birds and mammals of marine ecosystems in different geographical areas. The aim of this study was to determine the distribution of PFOS and PFOA in blood samples of the marine turtle Caretta caretta, using a minimally invasive sampling procedure. 49 blood samples of marine turtle, taken from several Italian marine turtle rescue centers, were analyzed. While PFOA was never detected, measurable concentrations of PFOS were found in 15 blood samples; the values show a range from 1.14ng/g to 28.51ng/g (wet wt.). No differences between groups of samples taken from different areas were found.
Показать больше [+] Меньше [-]Carbon and nitrogen stable isotope ratios and mercury concentration in the scalp hair of residents from Taiji, a whaling town
2013
Endo, Tetsuya | Hayasaka, Moriaki | Hisamichi, Yohsuke | Kimura, Osamu | Haraguchi, Koichi
We analyzed stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) as well as mercury (Hg) concentration in the scalp hair of Japanese who consumed whale meat and those who did not, and investigated the relationships among the δ13C and δ15N values and Hg concentration. The average δ15N and δ13C values of whale meat-eaters (10.11‰ and −18.5‰) were significantly higher than those of non-eaters (9.28‰ and −18.9‰), respectively. The average Hg concentration of whale meat-eaters (20.6μg/g) was significantly higher than that of non-eaters (2.20μg/g). Significant positive correlations were found between the δ13C and δ15N values and between the δ15N value and Hg concentration in the hair of whale meat-eaters, while the correlation between the δ15N value and Hg concentration was not statistically significant in the non-eaters. The consumption of whale meat may increase Hg concentration as well as δ15N and δ13C values in scalp hair.
Показать больше [+] Меньше [-]Drivers of estuarine benthic species distribution patterns following a restoration of a seagrass bed: A functional trait analyses
2013
Dolbeth, Marina | Cardoso, Patricia | Grilo, Tiago | Raffaelli, Dave | Pardal, Miguel Ângelo
We integrate information on functional diversity (FD) patterns from estuarine intertidal benthic communities from different habitats and along a temporal disturbance gradient, to understand the drivers of species coexistence patterns. Species and traits’ biomass levels seemed to be first determined by habitat filtering, selecting those traits better adapted to the biologically challenging estuarine environment. Within that subset of traits and within each habitat, biotic interactions were probably high, as evidenced by high α-diversity and community weighted mean differences. The former patterns hold for the disturbance/recovery scenario considered. However, as the estuary recovered, biomass became more distributed among different trait categories, consistent with increases in FD when the seagrass started to increase. Policy towards the restoration of seagrass bed and other biogenic structures, and improving the connectivity within adjacent systems were confirmed and suggested, as this would imply higher FD and potentially higher resilience to disturbance within the estuarine intertidal system.
Показать больше [+] Меньше [-]Incidence of plastic fragments among burrow-nesting seabird colonies on offshore islands in northern New Zealand
2013
Buxton, Rachel T. | Currey, Caitlin A. | Lyver, Philip O’B. | Jones, Christopher J.
Marine plastic pollution is ubiquitous throughout the world’s oceans, and has been found in high concentrations in oceanic gyres of both the northern and southern hemispheres. The number of studies demonstrating plastic debris at seabird colonies and plastic ingestion by adult seabirds has increased over the past few decades. Despite the recent discovery of a large aggregation of plastic debris in the South Pacific subtropical gyre, the incidence of plastics at seabird colonies in New Zealand is unknown. Between 2011 and 2012 we surveyed six offshore islands on the northeast coast of New Zealand’s North Island for burrow-nesting seabird colonies and the presence of plastic fragments. We found non-research related plastic fragments (0.031pieces/m2) on one island only, Ohinau, within dense flesh-footed shearwater (Puffinus carneipes) colonies. On Ohinau, we found a linear relationship between burrow density and plastic density, with 3.5 times more breeding burrows in areas with plastic fragments found. From these data we conclude that plastic ingestion is a potentially a serious issue for flesh-footed shearwaters in New Zealand. Although these results do not rule out plastic ingestion by other species, they suggest the need for further research on the relationship between New Zealand’s pelagic seabirds and marine plastic pollution.
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