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Echinoderms from Azores islands: An unexpected source of antibiotic resistant Enterococcus spp. and Escherichia coli isolates Полный текст
2013
Marinho, Catarina | Silva, Nuno | Pombo, Sofia | Santos, Tiago | Monteiro, Ricardo | Gonçalves, Alexandre | Micael, Joana | Rodrigues, Pedro | Costa, Ana Cristina | Igrejas, Gilberto | Poeta, Patrícia
The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp. and Escherichia coli, isolated from a total of 250 faecal samples of echinoderms collected from Azorean waters (Portugal). A total of 144 enterococci (120 Enterococcus faecium, 14 E. hirae, 8 E. faecalis, 2 E. gallinarum) and 10 E. coli were recovered. High percentages of resistance in enterococci were found for erythromycin, ampicillin, tetracyclin and ciprofloxacin. The erm(A) or erm(B), tet(M) and/or tet(L), vat(D), aac(6′)-aph(2″) and aph(3′)-IIIa genes were found in isolates resistant to erythromycin, tetracycline, quinupristin/dalfopristin, high-level gentamicin and high-level kanamycin, respectively. Resistance in E. coli isolates was detected for streptomycin, amikacin, tetracycline and tobramycin. The aadA gene was found in streptomycin-resistant isolates and tet(A)+tet(B) genes in tetracycline-resistant isolates. The data recovered are essential to improve knowledge about the dissemination of resistant strains through marine ecosystems and the possible implications involved in transferring these resistances either to other animals or to humans.
Показать больше [+] Меньше [-]Seasonal variation of metal contamination in the barnacles Pollicipes pollicipes in northwest coast of Portugal show clear correlation with levels in the surrounding water Полный текст
2013
Reis, Pedro A. | Salgado, María Antonia | Vasconcelos, Vitor
The concentrations of metals were determined in northwest (NW) coast of Portugal seawaters and soft tissues of goose barnacles Pollicipes pollicipes. P. pollicipes can be used for monitoring metal contamination in these coastal seawaters, because there were significant correlations (p<0.05) for all metals between soft tissues and seawaters during the four seasons. Metal concentrations in seawaters and P. pollicipes had significant (p<0.05) spatial and seasonal variations and mean log BAFs for Fe and Cd were higher than for Cr, Cu, Mn and Zn. Regarding the metal concentrations obtained in the coastal seawaters, all NW coast of Portugal should be classified as “Class IV – Bad”, except two locations (location 7 at Summer and location 10 at Winter), which should be classified as “Class III – Moderate”. However, considering the metal concentrations bioaccumulated in P. pollicipes, all locations should be classified as “Class III – Remarkably Polluted” during all seasons of 2011.
Показать больше [+] Меньше [-]Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality Полный текст
2013
Khosrovyan, A. | Rodríguez-Romero, A. | Salamanca, M.J. | Del Valls, T.A. | Riba, I. | Serrano, F.
Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality Полный текст
2013
Khosrovyan, A. | Rodríguez-Romero, A. | Salamanca, M.J. | Del Valls, T.A. | Riba, I. | Serrano, F.
The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions.
Показать больше [+] Меньше [-]Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality Полный текст
2013
Khosrovyan, Alla | Rodríguez-Romero, Araceli | Salamanca, M. José | Del Valls, T. A. | Riba, Inmaculada | Serrano-Bernardo, F. | Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions. © 2013 Elsevier Ltd. | Peer Reviewed
Показать больше [+] Меньше [-]Artificial radionuclides 90Sr and 241Am in the sediments of the Baltic Sea: Total and spatial inventories and some temporal trends Полный текст
2013
Hutri, Kaisa-Leena | Mattila, Jukka | Ikäheimonen, Tarja Tuulikki | Vartti, Vesa-Pekka
The Baltic Sea was contaminated by radioactivity following global nuclear fallout and later by the Chernobyl accident. Despite the decrease of radioactivity caused by radioactive decay, radionuclides have a prolonged residence time in the water of the Baltic Sea due to slow water exchange and relatively rapid sedimentation. Very little is known about the amounts or spatial differences of 90Sr and 241Am in the Baltic Sea sediments. In this study, 20 sediment cores taken around the Baltic Sea were investigated to estimate inventories of these radionuclides. The rough results show that the Chernobyl fallout added the amount of 90Sr in the same areas where the increase of 137Cs can be detected, whereas this is not the case for 241Am which is more evenly distributed in the sea bottom. In addition, local differences occur in the concentrations. These results are an important amendment to the radioactivity baseline of the Baltic Sea.
Показать больше [+] Меньше [-]Prevalence and composition of marine debris in Brown Booby (Sula leucogaster) nests at Ashmore Reef Полный текст
2013
Lavers, Jennifer L. | Hodgson, Jarrod C. | Clarke, Rohan H.
Anthropogenic debris is ubiquitous in the marine environment and has been reported to negatively impact hundreds of species globally. Seabirds are particularly at risk from entanglement in debris due to their habit of collecting food and, in many cases, nesting material off the ocean’s surface. We compared the prevalence and composition of debris in nests and along the beach at two Brown Booby (Sula leucogaster) colonies on Ashmore Reef, Timor Sea, a remote area known to contain high densities of debris transported by ocean currents. The proportion of nests with debris varied across islands (range 3–31%), likely in response to the availability of natural nesting materials. Boobies exhibited a preference for debris colour (white and black), but not type. The ephemeral nature of Brown Booby nests on Ashmore Reef may limit their utility as indicators of marine pollution, however monitoring is recommended in light of increasing demand for plastic products.
Показать больше [+] Меньше [-]Trace element content of seagrasses in the Leschenault Estuary, Western Australia Полный текст
2013
Kilminster, Kieryn
Estuarine environments are particularly vulnerable to human impacts. In this study, trace elements in Ruppia megacarpa, Halophila ovalis, sediment and porewater were analysed to assess the potential contamination of the Leschenault Estuary, Western Australia, from a primarily agricultural drain. Sediment concentrations of Cd, Cu, Mn, and Ni and were highest nearest the drain while Al, As, Cr, Fe and Zn and were highest further from the drain. H. ovalis showed greater accumulation of Fe, Al, and As than R. megacarpa. Concentrations of Fe, Al, As, and Ni were generally higher in below-ground plant parts than above, suggesting uptake of these trace elements via the sediment-route pathway. This study suggested that the drain was a source of Cu and Mn, with these elements entering the estuary through water inflows. As and Fe, were highest furthest from the drain suggesting input of trace elements from sources other than the drain under study.
Показать больше [+] Меньше [-]Baseline of the butyltin distribution in surface sediments (0–20cm) of the Elbe estuary (Germany, 2011) Полный текст
2013
Wetzel, Markus A. | Winterscheid, Axel | Wahrendorf, Dierk-Steffen
The concentrations of the butyltin (BT) species tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) were measured in the surface sediments (0–20cm) at 29 sites of the Elbe estuary in 2011. TBT values ranged from ‘undetectable’ to 41ngSng−1 dry weight (d.w.) with the two highest values measured in the inner section of the estuary near the port of Hamburg (32 and 41ngSng−1 d.w.). TBT, DBT, and MBT showed significant decreases towards the estuarine mouth (Spearman’s rho −0.660, −0.685, and −0.583, respectively, p<0.001). The degradation of TBT, assessed by the BT degradation index (BDI), showed a rising trend from the port of Hamburg towards the mouth of the estuary, though not a significant one (Spearman’s correlation, p=0.066). Annual sedimentation rates did not show any significant correlations (Spearman’s correlation) to BT pollution or to the butyltin degradation index (BDI).
Показать больше [+] Меньше [-]Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid–base and ion-regulatory abilities Полный текст
2013
Calosi, P. | Rastrick, S.P.S. | Graziano, M. | Thomas, S.C. | Baggini, C. | Carter, H.A. | Hall-Spencer, J.M. | Milazzo, M. | Spicer, J.I.
Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid–base and ion-regulatory abilities Полный текст
2013
Calosi, P. | Rastrick, S.P.S. | Graziano, M. | Thomas, S.C. | Baggini, C. | Carter, H.A. | Hall-Spencer, J.M. | Milazzo, M. | Spicer, J.I.
To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species’ ability to cope with elevated CO2, we investigated the acid–base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in closely-related taxa divergent physiological capabilities underlie differences in taxa distribution around the CO2 vent. It is concluded that species distribution under the sort of elevated CO2 conditions occurring with leakages from geological storages and future ocean acidification scenarios, may partly be determined by quite subtle physiological differentiation.
Показать больше [+] Меньше [-]Distribution of sea urchins living near shallow water CO2 vents is dependent upon species acid-base and ion-regulatory abilities Полный текст
2013
Calosi, Piero | Rastrick, S P S | Graziano, M | Thomas, S C | Baggini, Cecilia | Carter, H A | Hall-Spencer, Jason M | Milazzo, Marco | Spicer, John I
An analysis of ozone variation in the Greater Athens Area using Granger Causality Полный текст
2013
Sfetsos, Athanasios | Vlachogiannis, Diamando
Air pollution in urban areas is a topic of interest for many researchers as it impacts negatively the human health, the environment and the quality of life. As part of the effort in exploring ways for efficient and timely assessment of the urban air pollution patterns and their association with the local meteorology and photochemistry, an advanced statistical approach is proposed for the analysis of the spatiotemporal ozone (O3) variations and interdependencies to other pollutants. The focus of the work is placed on the investigation and determination of the causality between the local and regional factors causing the observed ozone variability, by applying a holistic methodology on multiple–year meteorological data and air pollution monitoring data, referenced in Athens (Greece). The methodology includes the Positive Matrix Factorization (PMF), for data scaling and reduction, a k–means clustering algorithm, for determining groups of data with common properties, and importantly, the Granger Causality test, for obtaining the causal links between the ozone and nitrogen oxides as well as the local meteorological conditions. The methodology revealed six dominant combined patterns of weather and air pollution. The application of the Granger Causality allowed the determination of relationships across the pollution patterns of dispersed geographic locations and the interdependence of those with the local meteorological conditions and photochemistry effects.
Показать больше [+] Меньше [-]Gaseous oxidized mercury dry deposition measurements in the Four Corners area and Eastern Oklahoma, U.S.A Полный текст
2013
Sather, Mark E. | Mukerjee, Shaibal | Smith, Luther | Mathew, Johnson | Jackson, Clarence | Callison, Ryan | Scrapper, Larry | Hathcoat, April | Adam, Jacque | Keese, Danielle | Ketcher, Philip | Brunette, Robert | Karlstrom, Jason | Van der Jagt, Gerard
Gaseous oxidized mercury (GOM) dry deposition measurements using surrogate surface passive samplers were collected in the Four Corners area and eastern Oklahoma from August, 2009–August, 2011. Using data from a six site area network, a characterization of the magnitude and spatial extent of ambient mercury pollution in the arid Four Corners area was accomplished, which included the observation of a strong regional signature in the GOM dry deposition data set. GOM dry deposition rate estimates ranged from 0.4–1.0 ng/m2 h at the six Four Corners area monitoring sites, while the GOM dry deposition rate estimate at the eastern Oklahoma monitoring site was lower at 0.2 ng/m2 h. The highest GOM dry deposition estimates were recorded during the spring and summer while the lowest GOM dry deposition estimates were recorded during the fall and winter. During the second year of this study the highest annual GOM dry deposition estimate so far measured in the United States (U.S.) with smooth–edge surrogate surface passive samplers, 10 889 ng/m2, was recorded at the Mesa Verde National Park site, a site at which the two– year cumulative GOM dry deposition estimate exceeded the mercury wet deposition estimate. GOM dry deposition estimates during the second year of the study were statistically significantly higher than the first year of the study at six of the seven sites. The data from this study provide a two–year baseline of GOM dry deposition data in the Four Corners area and eastern Oklahoma immediately before the current implementation of new U.S. power plant and boiler mercury control regulations which will significantly reduce mercury emissions from those two sectors of local and regional anthropogenic mercury emission sources.
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