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Effects of CO2 on benthic biota: An in situ benthic chamber experiment in Storfjorden (Norway)
2013
Ishida, Hiroshi | Golmen, Lars G. | West, Julia | Kruger, Martin | Coombs, Patricia | Berge, John Arthur | Fukuhara, Tastuo | Magi, Michimasa | Kita, Jun
Carbon capture and storage (CCS) methods, either sub-seabed or in ocean depths, introduces risk of CO2 leakage and subsequent interaction with the ecosystem. It is therefore important to obtain information on possible effects of CO2. In situ CO2 exposure experiments were carried out twice for 10days during 2005 using a Benthic Chamber system at 400m depth in Storfjorden, Norway. pCO2 in the water above the sediment in the chambers was controlled at approximately 500, 5000 and 20,000μatm, respectively. This article describes the experiment and the results from measured the biological responses within the chamber sediments. The results show effects of elevated CO2 concentrations on biological processes such as increased nanobenthos density. Methane production and sulphate reduction was enhanced in the approximately 5000μatm chamber.
Afficher plus [+] Moins [-]Contamination levels and spatial distributions of heavy metals and PAHs in surface sediment of Imam Khomeini Port, Persian Gulf, Iran
2013
Abdollahi, Sajad | Raoufi, Zeinab | Faghiri, Iraj | Savari, Ahmad | Nikpour, Yadolah | Mansouri, Ali
Imam Khomeini Port (IKP) is the largest Iranian commercial port. Because of many petrochemical industries and urban areas are located around this port and also having heavy ship traffic, concentrations of PAHs, mercury and other heavy metals were measured as the first time in surface sediment of the jetties. The highest concentrations of PAHs, Hg, Cu, Pb and Fe were recorded at Site 1, located in the vicinity of the petrochemical industrial zone, where ships are repaired. The highest concentration of Zn was found at Site 4, which is the jetty for loading mineral materials. The comparison between measured values in this study and some sediment quality guidelines indicated that the concentrations of mercury and PAHs are much higher than other studies. Also, the ratios of PAHs in the stations showed a mixture of both of pyrolytic and petrogenic sources with a dominance of pyrolytic sources.
Afficher plus [+] Moins [-]Characterization of epibenthic and demersal megafauna at Mississippi Canyon 252 shortly after the Deepwater Horizon Oil Spill
2013
Valentine, Marla M. | Benfield, Mark C.
The Deepwater Horizon Oil Spill resulted in the release of a large quantity of oil and gas into the northern Gulf of Mexico from a bathypelagic source. Due to a lack of pre-spill quantitative data the baseline condition of the communities near the spill site is unknown. This makes it difficult to determine the impact of the spill on deepwater megafauna. Remotely operated vehicles were used to quantify megafauna at five study sites during August and September 2010:2000m north, west, south, and east, and 500m north of the Macondo well. Comparisons of animal abundances indicated that 2000m-N and 2000m-W had the greatest taxonomic richness and highest abundances while 2000m-E had slightly lower values. In contrast 500m-N and 2000m-S had the lowest taxonomic richness and abundances. Our study also suggests that certain taxa were potentially more resistant or sensitive to the spill.
Afficher plus [+] Moins [-]Bioavailability of heavy metals in water and sediments from a typical Mediterranean Bay (Málaga Bay, Region of Andalucía, Southern Spain)
2013
Alonso Castillo, M.L. | Sánchez Trujillo, I. | Vereda Alonso, E. | García de Torres, A. | Cano Pavón, J.M.
Concentrations of heavy metals were measured in sediment and water from Málaga Bay (South Spain). In the later twentieth century, cities such as Málaga, have suffered the impact of mass summer tourism. The ancient industrial activities, and the actual urbanization and coastal development, recreation and tourism, wastewaters treatment facilities, have been sources of marine pollution. In sediments, Ni was the most disturbing metal because Ni concentrations exceeded the effects range low (ERL), concentration at which toxicity could start to be observed in 85% of the samples analyzed. The metal bioavailability decreased in the order: Cd>Ni>Pb>Cu>Cr. In the sea water samples, Cd and Pb were the most disturbing metals because they exceeded the continuous criteria concentration (CCC) of US EPA in a 22.5% and 10.0% of the samples, respectively. Statistical analyses (ANOVA, PCA, CA) were performed.
Afficher plus [+] Moins [-]Antibiotic resistance of Shewanella putrefaciens isolated from shellfish collected from the West Sea in Korea
2013
Kang, Chang-Ho | Shin, Yujin | Jeon, HanEul | Choi, Jae-Ho | Jeong, SuYeon | So, Jae-Seong
In this study, we isolated and characterized Shewanella putrefaciens from shellfish harvested from the West Sea in Korea. For the initial isolation of S. putrefaciens, LB agar plates supplemented with ferrous sulfate and sodium thiosulfate were inoculated with shellfish homogenates, incubated for 24h, and then black colonies were selected. Gram-negative and catalase-positive colonies were subsequently confirmed by PCR assays and API 20E kit test system. The Shewanella-specific 16S rRNA and gyrB genes were used to design S. putrefaciens-specific PCR primers. From 6 species of shellfish tested, 24 S. putrefaciens strains were isolated. These 24 isolates had the following profiles of resistance against 16 antibiotics: all the isolates were resistant to cephalothin and vancomycin and 95.8% were resistant to ampicillin. Here, we report the isolation of S. putrefaciens from shellfish and our results point to a new possible route for exposing healthy individuals to S. putrefaciens.
Afficher plus [+] Moins [-]Source characterization and spatio–temporal evolution of the metal pollution in the sediments of the Basque estuaries (Bay of Biscay)
2013
Legorburu, Irati | Rodríguez, José Germán | Borja, Angel | Menchaca, Iratxe | Solaun, Oihana | Valencia Rincón, Victoriano | Galparsoro, Ibon | Larreta, Joana
According to Water Framework Directive requirements, Member States must identify and analyze effects derived from human pressures in aquatic systems. As different kind of pressures can impact water bodies at different scales, analyses of spatio-temporal evolution of water bodies becomes essential in order to understand ecosystem responses. In this investigation, an analysis of spatio-temporal evolution of sedimentary metal pollution (Cd, Cr, Cu, Hg, Ni, Pb, Zn) in 12 Basque estuaries (Bay of Biscay) is presented. Data collected in extensive sampling surveys is the basis for the GIS-based statistical approach used. The implementation of pollution abatement measures is reflected in a long-term decontamination process, mostly evident in estuaries with highest historical sediment pollution levels. Spatial evolution is determined by either naturally occurring or human driven processes. Such spatial processes are more obviously being reflected in estuaries with lower historical sediment pollution levels.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
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