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Effects of elevated CO2 on the reproduction of two calanoid copepods 全文
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S. | Somerfield, Paul J. | Findlay, Helen S. | Spicer, John I.
Effects of elevated CO2 on the reproduction of two calanoid copepods 全文
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S. | Somerfield, Paul J. | Findlay, Helen S. | Spicer, John I.
Some planktonic groups suffer negative effects from ocean acidification (OA), although copepods might be less sensitive. We investigated the effect of predicted CO2 levels (range 480–750ppm), on egg production and hatching success of two copepod species, Centropages typicus and Temora longicornis. In these short-term incubations there was no significant effect of high CO2 on these parameters. Additionally a very high CO2 treatment, (CO2=9830ppm), representative of carbon capture and storage scenarios, resulted in a reduction of egg production rate and hatching success of C. typicus, but not T. longicornis. In conclusion, reproduction of C. typicus was more sensitive to acute elevated seawater CO2 than that of T. longicornis, but neither species was affected by exposure to CO2 levels predicted for the year 2100. The duration and seasonal timing of exposures to high pCO2, however, might have a significant effect on the reproduction success of calanoid copepods.
显示更多 [+] 显示较少 [-]Seawater carbonate chemistry and reproduction of the two calanoid copepods Centropages typicus and Temora longicornis in a laboratory experiment 全文
2013
McConville, Kristian | Halsband, Claudia | Fileman, Elaine S | Somerfield, Paul J | Findlay, Helen S | Spicer, John I
Some planktonic groups suffer negative effects from ocean acidification (OA), although copepods might be less sensitive. We investigated the effect of predicted CO2 levels (range 480-750 ppm), on egg production and hatching success of two copepod species, Centropages typicus and Temora longicornis. In these short-term incubations there was no significant effect of high CO2 on these parameters. Additionally a very high CO2 treatment, (CO2 = 9830 ppm), representative of carbon capture and storage scenarios, resulted in a reduction of egg production rate and hatching success of C. typicus, but not T. longicornis. In conclusion, reproduction of C. typicus was more sensitive to acute elevated seawater CO2 than that of T. longicornis, but neither species was affected by exposure to CO2 levels predicted for the year 2100. The duration and seasonal timing of exposures to high pCO2, however, might have a significant effect on the reproduction success of calanoid copepods.
显示更多 [+] 显示较少 [-]Distribution of the genus Alexandrium (Halim) and paralytic shellfish toxins along the coastline of New South Wales, Australia 全文
2013
Farrell, Hazel | Brett, Steve | Ajani, Penelope | Murray, Shauna
Blooms of Alexandrium species, in particular the species Alexandrium catenella, accounted for more than 50% of algal related, shellfish aquaculture harvest zone closures in New South Wales (NSW) Australia since 2005. While there are indications that species of Alexandrium are more abundant than they were formerly, there is little data available on the spatial and temporal distribution and abundance of the genus in NSW. A six and a half year dataset comprising a total of 8649 fortnightly samples from 31 estuaries spread over 2000km of NSW coastline was analysed. The greatest abundances of Alexandrium spp. were observed during the austral Spring and Summer, in estuaries in the mid and southern latitudes of the state. In identifying these high risk zones, we propose variables such as season, temperature, rainfall and estuarine flushing to be targeted in intensive site specific studies, to support the development of predictive tools for resource managers.
显示更多 [+] 显示较少 [-]Variations of 210Po and 210Pb concentration in mussels (Mytilus galloprovincialis) from Didim and Izmir Bay (Turkish coast of Aegean Sea) 全文
2013
Aközcan, S. | Uğur Görgün, A.
In this study, the activity concentrations of 210Po and 210Pb were determined in mussels (Mytilus galloprovincialis) collected from Didim and Izmir Bay (Turkish coast of Aegean Sea) during the period of April 2006–March 2007. The concentrations activity of 210Po were determined spectroscopically through its 5.30MeV alpha particle emission, using 209Po as an internal tracer. The 210Pb activity concentrations were determined from the ingrowth of 210Po, assuming zero initial 210Po activity. The results of 210Po and 210Pb activity concentrations were found to vary between 34±9 and 1855±98Bqkg−1 dry weight and ND (lower than limit of detection) – 64±6Bqkg−1 dry weight, respectively. 210Po/210Pb ratio ranged between 1.00 and 106.87. The highest 210Po activities were found in mussels collected from Didim.
显示更多 [+] 显示较少 [-]Is the distribution of the lancelet Branchiostoma caribaeum affected by sewage discharges? An analysis at multiple scales of variability 全文
2013
Barboza, Carlos Alberto de Moura | Hadlich, Heliatrice Louise | Sandrini-Neto, Leonardo | Martins, César de Castro | Lana, Paulo da Cunha
Spatial variation in the density and biomass of Branchiostoma caribaeum was analyzed along a sewage contamination gradient identified by fecal steroids in a subtropical estuary, southern Brazil. Sampling, repeated in the austral winter and summer, followed a hierarchical design nested at four spatial scales (sector>1km; area>100m; site>10m; replicate<1m). Density and biomass were significantly lower at sites characterized by high concentrations of fecal steroids. The best combinations of variables that explained the biological similarities among sites involved contamination indicators. Most of the variation of biological data was found at the smallest scales and could be related with the sediment texture. Our study highlighted the usefulness of a multi-scale perspective to evaluate distribution patterns of benthic invertebrates as a biological indication of environmental pollution. Gradient analyses at larger spatial scales may be invalidated by the patchy distribution of benthic fauna if they do not account for such small scale variability.
显示更多 [+] 显示较少 [-]Leisure boating noise as a trigger for the displacement of the bottlenose dolphins of the Cres–Lošinj archipelago (northern Adriatic Sea, Croatia) 全文
2013
Rako, Nikolina | Fortuna, Caterina Maria | Holcer, Draško | Mackelworth, Peter | Nimak-Wood, Maja | Pleslić, Grgur | Sebastianutto, Linda | Vilibić, Ivica | Wiemann, Annika | Picciulin, Marta
The waters of the Cres–Lošinj archipelago are subject to intense boat traffic related to the high number of leisure boats frequenting this area during the summer tourist season. Boat noise dominates the acoustic environment of the local bottlenose dolphin (Tursiops truncatus) population. This study investigates the spatial and temporal change in the underwater noise levels due to intense boating, and its effect on the distribution of the bottlenose dolphins. In the period 2007–2009 sea ambient noise (SAN) was sampled across ten acoustic stations. During data collection the presence of leisure boats was recorded if they were within 2km of the sampling station. Bottlenose dolphin spatial distribution was monitored in the same period. Results showed a strong positive correlation between high SAN levels and boat presence, particularly in the tourist season. Dolphin distribution indicated significant seasonal displacements from noisy areas characterized by the intense leisure boating.
显示更多 [+] 显示较少 [-]Advanced diagnostics applied to fish liver tumours: Relating pathology to underlying molecular aetiology 全文
2013
Lerebours, Adélaïde | Bignell, John P. | Stentiford, Grant D. | Feist, Stephen W. | Lyons, Brett P. | Rotchell, Jeanette M.
Liver tumours in flatfish have been diagnosed using histopathology for decades in order to monitor the impacts of marine pollution in coastal and estuarine environments. This traditional method has been coupled with molecular analyses of tumours in the liver of the dab, Limanda limanda, in order to elucidate underpinning molecular level aetiology of such disease. A laser capture microdissection technique for molecular investigation of cancer has been applied in fish. The present study provides optimized steps for environmental sample utilisation: a procedure for field sample collection and handling; a method allowing reliable identification of lesions on frozen tissue sections; and, downstream molecular analyses of tumourigenesis markers (retinoblastoma gene) in laser microdissected samples. This approach facilitates the use of wild flatfish as a model of environmentally-induced tumourigenesis, and has wide applicability to any disease pathology for which the underpinning molecular aetiology is required.
显示更多 [+] 显示较少 [-]The effects of storm-drains with periodic flows on intertidal algal assemblages in ‘Ewa Beach (O‘ahu), Hawai‘i 全文
2013
Cox, T.E. | Foster, M.S.
Storm-water drainage systems have potential to collect and focus nutrient enriched runoff into coastal systems. Storm-drain effluent could support macroalgal production and result in altered communities. To test this hypothesis, we assessed species composition and percent cover of native and non-native benthic macroalgae at eight intertidal sites along ‘Ewa Beach, Hawai‘i. Three sites contain storm-drainage outlets (drain 16–52acres) that deliver effluent into the intertidal zone whereas five sites were located⩾100m away and served as comparisons to determine differences related to the presence of storm-water. Results revealed lush and diverse macroalgal assemblages, similar at all sites. Furthermore, the abundance of non-native species (Acanthophora spicifera, Hypnea musciformis) was not related to presence of storm-drains. The finding that macroalgal assemblages are not related to storm-waters is contrary to an earlier investigation in the same location and underscores the importance of sampling design and habitat variation when assessing impacts.
显示更多 [+] 显示较少 [-]Organochlorine pesticides and chlorobiphenyls in the blubber of bycaught female common dolphins from England and Wales from 1992–2006 全文
2013
Law, Robin J. | Bersuder, Philippe | Barry, Jon | Barber, Jon | Deaville, Rob | Barnett, James | Jepson, Paul D.
We report concentrations of organochlorine pesticides (HCB, HCHs, DDTs, dieldrin) and PCBs in the blubber of 43 common dolphins bycaught in fisheries operating off the SW coast of the UK from 1992 to 2006. Concentrations of ΣDDT (summed p,p′-DDT and its metabolites, p,p′-DDE and p,p′-TDE) and of 25 summed CB congeners ranged from 0.2 to 16.1 and 2.1 to 62.4mgkg−1 lipid weight, respectively. Concentrations of sum HCH, HCB and dieldrin were lower, ranging from not detected to 0.14, 0.01 to 0.27 and 0.01 to 0.73mgkg−1 lipid weight, respectively. All contaminants studied showed a downward time trend but only that for HCHs was statistically significant. Overall, 72% of the dolphins analysed had blubber PCB concentrations above an established toxicity threshold value.
显示更多 [+] 显示较少 [-]Seemingly unrelated intervention time series models for effectiveness evaluation of large scale environmental remediation 全文
2013
Ip, Ryan H.L. | Li, W.K. | Leung, Kenneth M.Y.
Large scale environmental remediation projects applied to sea water always involve large amount of capital investments. Rigorous effectiveness evaluations of such projects are, therefore, necessary and essential for policy review and future planning. This study aims at investigating effectiveness of environmental remediation using three different Seemingly Unrelated Regression (SUR) time series models with intervention effects, including Model (1) assuming no correlation within and across variables, Model (2) assuming no correlation across variable but allowing correlations within variable across different sites, and Model (3) allowing all possible correlations among variables (i.e., an unrestricted model). The results suggested that the unrestricted SUR model is the most reliable one, consistently having smallest variations of the estimated model parameters. We discussed our results with reference to marine water quality management in Hong Kong while bringing managerial issues into consideration.
显示更多 [+] 显示较少 [-]Desorption kinetics of hydrophobic organic contaminants from marine plastic pellets 全文
2013
Endo, Satoshi | Yuyama, Masaki | Takada, Hideshige
This study investigated the desorption behavior of polychlorinated biphenyls (PCBs) from marine plastic pellets. Long-term desorption experiments were conducted using field-collected polyethylene (PE) pellets. The results indicate that the desorption kinetics highly depends on the PE-water partition coefficients of PCB congeners. After 128d of the experiment, the smallest congener considered (CB 8) had desorbed nearly completely (98%), whereas major fractions (90–99%) of highly chlorinated congeners remained in the pellets. An intraparticle diffusion model mostly failed to reproduce the desorption kinetics, whereas an aqueous boundary layer (ABL) diffusion model well approximated the data. The desorption half-lives are estimated to 14d to 210years for CB 8 to CB 209 in an actively stirred solution (ABL thickness: 30μm). Addition of methanol to water enhanced the desorption to a large extent. A need for further work to explore roles of organic matter in facilitating solute transfer is suggested.
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