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DNA strand breaks (comet assay) in blood lymphocytes from wild bottlenose dolphins
2013
Lee, Richard F. | Bulski, Karrie | Adams, Jeffrey D. | Peden-Adams, Margie | Bossart, Gregory D. | King, Lydia | Fair, Patricia A.
The comet assay was carried out on blood lymphocytes from a large number of wild dolphins (71 from Indian River Lagoon, FL, USA; 51 from Charleston Harbor, SC, USA) and provides a baseline study of DNA strand breaks in wild dolphin populations. There were no significant differences in the comet assay (%DNAintail) results between the different age and sex categories. Significant difference in DNA strand breaks were found between Charleston Harbor dolphins (median – 17.4%DNAintail) and Indian River Lagoon dolphins (median – 14.0%DNAintail). A strong correlation found between T-cell proliferation and DNA strand breaks in dolphin lymphocytes suggests that dolphins with a high numbers of DNA strand breaks have a decreased ability to respond to infection. Higher concentrations of genotoxic agents in Charleston Harbor compared with Indian River lagoon may have been one of the causes of higher DNA strand breaks in these dolphins.
Mostrar más [+] Menos [-]Temporal variability and climatology of hydrodynamic, water property and water quality parameters in the West Johor Strait of Singapore
2013
Behera, Manasa Ranjan | Chun, Cui | Palani, Sundarambal | Tkalich, Pavel
The study presents a baseline variability and climatology study of measured hydrodynamic, water properties and some water quality parameters of West Johor Strait, Singapore at hourly-to-seasonal scales to uncover their dependency and correlation to one or more drivers. The considered parameters include, but not limited by sea surface elevation, current magnitude and direction, solar radiation and air temperature, water temperature, salinity, chlorophyll-a and turbidity. FFT (Fast Fourier Transform) analysis is carried out for the parameters to delineate relative effect of tidal and weather drivers. The group and individual correlations between the parameters are obtained by principal component analysis (PCA) and cross-correlation (CC) technique, respectively. The CC technique also identifies the dependency and time lag between driving natural forces and dependent water property and water quality parameters. The temporal variability and climatology of the driving forces and the dependent parameters are established at the hourly, daily, fortnightly and seasonal scales.
Mostrar más [+] Menos [-]Changes in zooplankton communities along a mercury contamination gradient in a coastal lagoon (Ria de Aveiro, Portugal)
2013
Cardoso, Patrícia Gonçalves | Marques, Sónia Cotrim | D’Ambrosio, Mariaelena | Pereira, Eduarda | Duarte, Armando Costa | Azeiteiro, Ulisses | Pardal, Miguel Ângelo
The main objective of this paper was to evaluate the impact of mercury on the zooplankton communities’ structure and functioning and their bioaccumulation patterns along a contamination gradient in a temperate coastal lagoon. Our results demonstrated that total abundance was not negatively affected by Hg contamination, since the most contaminated areas presented the highest values, being the copepod Acartia tonsa the dominant species, which means that it is a very well adapted and tolerant species to mercury. Nevertheless, negative effects were observed in terms of species diversity, since the most contaminated areas presented the lowest values of species richness, evenness and heterogeneity. Moreover, the spatial mercury gradient was reflected on the bioaccumulation patterns of the zooplankton communities. This reinforces the idea that zooplankton can be considered as an important vehicle of mercury transfer through the food pelagic web since it constitutes a primordial food resource for several commercial fish species.
Mostrar más [+] Menos [-]Natural antifouling compounds produced by a novel fungus Aureobasidium pullulans HN isolated from marine biofilm
2013
Gao, Min | Su, Rongguo | Wang, Ke | Li, Xuzhao | Lu, Wei
A fungus, Aureobasidium pullulans, was isolated from marine biofilm and identified. A bioassay-guided fractionation procedure was developed to isolate and purify antifouling compounds from A. pullulans HN. The procedure was: fermentation broth—aeration and addition of sodium thiosulfate–graduated pH and liquid–liquid extraction—SPE purification—GC–MS analysis. Firstly, the fermentation broth was tested for its toxicity. Then it was treated with aeration and addition of sodium thiosulfate, and its toxicity was almost not changed. Lastly, antifouling compounds were extracted at different pH, the extract had high toxicity at pH 2 but almost no toxicity at pH 10, which suggested the toxicants should be fatty acids. The EC50 of the extract against Skeletonema costatum was 90.9μgml−1, and its LC50 against Balanus amphitrete larvae was 22.2μgml−1. After purified by HLB SPE column, the EC50 of the extract against S. costatum was 49.4μgml−1. The myristic and palmitic acids were found as the main toxicants by GC–MS.
Mostrar más [+] Menos [-]Biomagnification of persistent chlorinated and brominated contaminants in food web components of the Yellow Sea
2013
Byun, Gyo-Hyuk | Moon, Hyo-Bang | Ch'oe, Chŏng-hwa | Hwang, Jeomshik | Kang, Chang-Keun
Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) were measured in 32 species inhabiting the Yellow Sea to assess their bioaccumulation potentials. The concentrations in these samples were lower than those reported for other countries or locations. Relatively high levels of BDE 209 in biota suggest an ongoing source of deca-BDE technical mixing within the Yellow Sea. The accumulation profiles of PCBs were uniform between species, but the concentrations of OCPs and PBDEs varied widely. Pelagic and benthic food-chain components were separated by their δ13C values. Significant positive correlations between δ15N and PCB 153, PCB 138, p,p′-DDE, oxy-chlordane, and trans-nonachlordane were found only for pelagic consumers, indicating that the pelagic food chain is an important bioaccumulation pathway for selected PCB and OCP compounds. The other compounds did not show any biomagnification through benthic and pelagic food chains, suggesting the lower bioaccumulation potentials of these contaminants.
Mostrar más [+] Menos [-]Plastic debris in Mediterranean seabirds
2013
Codina-García, Marina | Militão, Teresa | Moreno Lázaro, Javier | González-Solís, Jacob
Plastic debris is often ingested by marine predators and can cause health disorders and even death. We present the first assessment of plastic ingestion in Mediterranean seabirds. We quantified and measured plastics accumulated in the stomach of 171 birds from 9 species accidentally caught by longliners in the western Mediterranean from 2003 to 2010. Cory’s shearwaters (Calonectris diomedea) showed the highest occurrence (94%) and large numbers of small plastic particles per affected bird (on average N=15.3±24.4 plastics and mass=23.4±49.6mg), followed by Yelkouan shearwaters (Puffinus yelkouan, 70%, N=7.0±7.9, 42.1±100.0mg), Balearic shearwaters (Puffinus mauretanicus, 70%, N=3.6±2.9, 5.5±9.7mg) and the rest of species (below 33%, N=2.7, 113.6±128.4mg). Plastic characteristics did not differ between sexes and were not related to the physical condition of the birds. Our results point out the three endemic and threatened shearwater species as being particularly exposed to plastic accumulation.
Mostrar más [+] Menos [-]Promoting invasive species control and eradication in the sea: Options for managing the tunicate invader Didemnum vexillum in Sitka, Alaska
2013
McCann, Linda D. | Holzer, Kimberly K. | Davidson, Ian C. | Ashton, Gail V. | Chapman, Marnie D. | Ruiz, Gregory M.
Bioinvasions are a significant force of change – and economic and ecological threat – in marine ecosystems. The threat now encroaches on Alaska, which has had relatively few invasions compared to other global regions, prompting need to develop new incursion response tools. We appraised five ‘eco-friendly’ immersion treatment options (dilute acetic acid, dilute bleach, freshwater, brine and hypoxia) at either minute- or hour-scale exposures to kill the invasive tunicate Didemnum vexillum. Data revealed 100% treatment efficacy after two minutes in acetic acid, ten minutes in bleach, four hours in freshwater and over four hours in brine solution. We also demonstrated the importance of monitoring D. vexillum recovery for at least three weeks, since seemingly destroyed colonies rebounded during this timeframe. Combined, these findings provide insights towards a bay-scale eradication and post-border management plan applicable to the recent D. vexillum incursion in Whiting Harbor, Alaska and other shallow, inshore invasion sites.
Mostrar más [+] Menos [-]Trace metals associated with deep-sea tailings placement at the Batu Hijau copper–gold mine, Sumbawa, Indonesia
2013
Angel, Brad M. | Simpson, Stuart L. | Jarolimek, Chad V. | Jung, Rob | Waworuntu, Jorina | Batterham, Grant
The Batu Hijau copper–gold mine on the island of Sumbawa, Indonesia operates a deep-sea tailings placement (DSTP) facility to dispose of the tailings within the offshore Senunu Canyon. The concentrations of trace metals in tailings, waters, and sediments from locations in the vicinity of the DSTP were determined during surveys in 2004 and 2009. In coastal and deep seawater samples from Alas Strait and the South Coast of Sumbawa, the dissolved concentrations of Ag, As, Cd, Cr, Hg, Pb and Zn were in the sub μg/L range. Dissolved copper concentrations ranged from 0.05 to 0.65μg/L for all depths at these sites. Dissolved copper concentrations were the highest in the bottom-water from within the tailings plume inside Senunu Canyon, with up to 6.5μg Cu/L measured in close proximity to the tailings discharge. In general, the concentrations of dissolved and particulate metals were similar in 2004 and 2009.
Mostrar más [+] Menos [-]Risk assessment and national measure plan for oil and HNS spill accidents near Korea
2013
Lee, Moonjin | Jung, Jung-Yeul
Many oil and HNS spill accidents occur in the waters surrounding the Korean Peninsula because Korea is one of the biggest trading partners in the world. In this study, we analyzed the oil and HNS spill accidents that occurred between 1994 and 2005 and created risk matrices to assess these accidents. The worst scenarios of future oil and HNS spill accidents were established, and the maximum spill amounts were estimated using historic accident data and a correlation from IPIECA. The maximum spill amounts are estimated to be between 77,000 and 10,000tons of oil and HNS, respectively. One third of the spill materials should be removed using recovery equipment within three days of the spill event, according to the national measure plan. The capability of recovery equipment to remove spill materials can be estimated, and the equipment should then be prepared to mitigate the harmful effects of future oil and HNS accidents on humans and marine ecosystems.
Mostrar más [+] Menos [-]Chlorinated compounds and polybrominated diphenyl ethers (PBDEs) in mussels (Mytilus galloprovincialis) collected from Apulia Region coasts
2013
Giandomenico, Santina | Spada, Lucia | Annicchiarico, Cristina | Assennato, Giorgio | Cardellicchio, Nicola | Ungaro, Nicola | Leo, Antonella Di
This project was carried out to assess the levels and spatial distribution of organochlorine compounds in the coastal marine environment, using mussels as bioindicators to evaluate the coastal water quality. Levels of polychlorobiphenils (PCB), chlorinated pesticides (DDT isomers, HCH isomers, Aldrin, Dieldrin, alfa-Endosulfan, Hexachlorobenzene, Pentachlorobenzene) and polybrominated diphenyl ethers (PBDEs) were determined in tissues from mussels (Mytilus galloprovincialis) collected along the Apulia Region coasts (Mediterranean Sea). Results indicate that contamination by organochlorine compounds is higher in mussels sampled in the Ionian Sea than in those from the Adriatic Sea, with PCB levels up to seven times higher in mussels from Ionian than from the Adriatic Sea. Although PCB levels were above the maximum values indicated by both European Community (EC) and National regulation in several sample sites, the PCB concentrations were particularly high in some stations, suggesting that these locations require a much specific attention. Conversely, results on the mussel contamination by PBDEs highlight their ubiquitous environmental distribution, and underline the need to establish the maximum level for these compounds in foodstuff, according to European Regulations.
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