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Impact of cigarette butt leachate on tidepool snails Texto completo
2015
Booth, David J. | Gribben, Paul | Parkinson, Kerryn
Impact of cigarette butt leachate on tidepool snails Texto completo
2015
Booth, David J. | Gribben, Paul | Parkinson, Kerryn
In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2h soak time) after 8days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species.While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently.
Mostrar más [+] Menos [-]Impact of cigarette butt leachate on tidepool snails Texto completo
2015
Booth, DJ | Gribben, P | Parkinson, K
© 2015 Elsevier Ltd. In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2. h soak time) after 8. days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species. While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently.
Mostrar más [+] Menos [-]Changes in bioaccumulation and translocation patterns between root and leafs of Avicennia schaueriana as adaptive response to different levels of metals in mangrove system Texto completo
2015
Souza, Iara da C. | Rocha, Lívia D. | Morozesk, Mariana | Bonomo, Marina M. | Arrivabene, Hiulana P. | Duarte, Ian D. | Furlan, Larissa M. | Monferrán, Magdalena V. | Mazik, K. (Krysia) | Elliott, Michael | Matsumoto, Silvia T. | Milanez, Camilla R.D. | Wunderlin, Daniel A. | Fernandes, Marisa N.
Changes in bioaccumulation and translocation patterns between root and leafs of Avicennia schaueriana as adaptive response to different levels of metals in mangrove system Texto completo
2015
Souza, Iara da C. | Rocha, Lívia D. | Morozesk, Mariana | Bonomo, Marina M. | Arrivabene, Hiulana P. | Duarte, Ian D. | Furlan, Larissa M. | Monferrán, Magdalena V. | Mazik, K. (Krysia) | Elliott, Michael | Matsumoto, Silvia T. | Milanez, Camilla R.D. | Wunderlin, Daniel A. | Fernandes, Marisa N.
Espírito Santo estuaries (Brazil) are impacted by industrial activities, resulting in contamination of water and sediments. This raise questions on biological uptake, storage and consequences of metal contamination to mangrove plants. The goal of this work was evaluating accumulation and translocation of metals from sediment to roots and leaves of Avicennia schaueriana, growing in areas with different degrees of contamination, correlating bioaccumulation with changes in its root anatomy. Highest bioconcentration factors (BCFs) were observed in plants growing in less polluted areas. Conversely, highest translocation factors were found in plants from highest polluted area, evidencing an adaptive response of A. schaueriana to less favourable conditions. Namely, the absorption of metals by roots is diminished when facing highest levels of metals in the environment; alternatively, plants seem to enhance the translocation to diminish the concentration of toxic metals in roots. Root also responded to highly polluted scenarios with modifications of its anatomy.
Mostrar más [+] Menos [-]Changes in bioaccumulation and translocation patterns between root and leafs of Avicennia schaueriana as adaptive response to different levels of metals in mangrove system Texto completo
2015
Souza, Iara da C. | Rocha, Lívia D. | Morozesk, Mariana | Bonomo, Marina M. | Arrivabene, Hiulana P. | Duarte, Ian D. | Furlan, Larissa M. | Monferran, Magdalena Victoria | Mazik, Krysia | Elliott, Michael | Matsumoto, Silvia T. | Milanez, Camilla R.D. | Wunderlin, Daniel Alberto | Fernandes, Marisa N.
Espírito Santo estuaries (Brazil) are impacted by industrial activities, resulting in contamination of water and sediments. This raise questions on biological uptake, storage and consequences of metal contamination to mangrove plants. The goal of this work was evaluating accumulation and translocation of metals from sediment to roots and leaves of Avicennia schaueriana, growing in areas with different degrees of contamination, correlating bioaccumulation with changes in its root anatomy. Highest bioconcentration factors (BCFs) were observed in plants growing in less polluted areas. Conversely, highest translocation factors were found in plants from highest polluted area, evidencing an adaptive response of A. schaueriana to less favourable conditions. Namely, the absorption of metals by roots is diminished when facing highest levels of metals in the environment; alternatively, plants seem to enhance the translocation to diminish the concentration of toxic metals in roots. Root also responded to highly polluted scenarios with modifications of its anatomy. | Fil: Souza, Iara da C.. Universidade Federal do São Carlos; Brasil | Fil: Rocha, Lívia D.. Universidade Federal do Espírito Santo; Brasil | Fil: Morozesk, Mariana. Universidade Federal do São Carlos; Brasil | Fil: Bonomo, Marina M.. Universidade Federal do São Carlos; Brasil | Fil: Arrivabene, Hiulana P.. Universidade Federal do Espírito Santo; Brasil | Fil: Duarte, Ian D.. Universidade Federal do Espírito Santo; Brasil | Fil: Furlan, Larissa M.. Universidade Federal do Espírito Santo; Brasil | Fil: Monferran, Magdalena Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina | Fil: Mazik, Krysia. University of Hull; Reino Unido | Fil: Elliott, Michael. University of Hull; Reino Unido | Fil: Matsumoto, Silvia T.. Universidade Federal do Espírito Santo; Brasil | Fil: Milanez, Camilla R.D.. Universidade Federal do Espírito Santo; Brasil | Fil: Wunderlin, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina | Fil: Fernandes, Marisa N.. Universidade Federal do São Carlos; Brasil
Mostrar más [+] Menos [-]Development of current and future pollutant emissions for Portugal Texto completo
2015
Sa, Elisa | Ferreira, Joana | Carvalho, Anabela | Borrego, C.
Development of current and future pollutant emissions for Portugal Texto completo
2015
Sa, Elisa | Ferreira, Joana | Carvalho, Anabela | Borrego, C.
Air pollutant emissions are a fundamental input for accurate air quality simulations. Therefore, a detailed estimation of current emissions should be performed, mainly for the activity sectors that have higher contributions to emission totals. In order to estimate air quality under climate change at regional scale, it is extremely important to provide the most accurate emission inventories based on the emission scenarios used as input for the global climate models. The Representative Concentration Pathways (RCPs) are the most recent developed emission scenarios. Emission inventories used in air quality simulations at regional scale for future periods should be based on these recent developments. In this sense, an Emission Projections under RCP scenarios (EmiPro–RCP) model was developed to assist the estimation of future emission inventories for GHG and common air pollutants. This paper describes the methodology developed under EmiPro–RCP model and presents the estimation of current and projected emissions for Portugal for CO, PM2.5, PM10, SOx, NOx, NMVOC and NH3, which will be used as input in air quality modeling systems. A comparison between the inventories was performed and the results indicated that all the RCPs scenarios predict a decrease in most of the air pollutant emissions until 2100, with the exception of NH3 that increases. The main decreases are found in the coastal zone of Portugal, mainly in Porto and Lisbon urban areas, while the NH3 increases are located not only in the coastal zone but also in the southern inland of Portugal.
Mostrar más [+] Menos [-]Development of current and future pollutant emissions for Portugal Texto completo
1000
Sa, Elisa | Ferreira, Joana | Carvalho, Anabela | Borrego, Carlos
Air pollutant emissions are a fundamental input for accurate air quality simulations. Therefore, a detailed estimation of current emissions should be performed, mainly for the activity sectors that have higher contributions to emission totals. In order to estimate air quality under climate change at regional scale, it is extremely important to provide the most accurate emission inventories based on the emission scenarios used as input for the global climate models. The Representative Concentration Pathways (RCPs) are the most recent developed emission scenarios. Emission inventories used in air quality simulations at regional scale for future periods should be based on these recent developments. In this sense, an Emission Projections under RCP scenarios (EmiPro–RCP) model was developed to assist the estimation of future emission inventories for GHG and common air pollutants. This paper describes the methodology developed under EmiPro–RCP model and presents the estimation of current and projected emissions for Portugal for CO, PM2.5, PM10, SOx, NOx, NMVOC and NH3, which will be used as input in air quality modeling systems. A comparison between the inventories was performed and the results indicated that all the RCPs scenarios predict a decrease in most of the air pollutant emissions until 2100, with the exception of NH3 that increases. The main decreases are found in the coastal zone of Portugal, mainly in Porto and Lisbon urban areas, while the NH3 increases are located not only in the coastal zone but also in the southern inland of Portugal.
Mostrar más [+] Menos [-]Study of chemical characteristics of particulate matter concentrations in Riyadh, Saudi Arabia Texto completo
2015
Alharbi, Badr | Shareef, Mohammed Mujtaba | Husain, Tahir
Particulate matter samples were collected from several locations during September 2011 and September 2012 in Riyadh, Saudi Arabia. In addition to determining particulate matter (as PM10) concentrations, the samples were analyzed for several metals and ions. PM concentration was approximately 3 times higher than the Country’s ambient air quality standards respectively. Metals and ions contributed to about 21.5% and 16.2% of the PM concentrations respectively. Summer vs. winter comparison showed that PM concentrations were approximately 84% higher in summer and the crustal matter species such as Fe, Mn, Ti, Ca+2, Mg+2 increased several folds in summer, primarily attributed to dust storms. The weekdays PM concentrations were 17% more than the weekend concentrations, indicating weekday activities contribute to the concentrations. The dust storms lead to over 200% increase in the PM and some elements primarily Al, Fe, Mg and Ca. Spatial comparison at industrial and residential locations revealed about 60% increase in PM concentrations and substantial increase in Zn, Mn, B, Mg, Fe, and Al and the ions K+, SO4--, and Cl- at industrial locations. Bivariate correlations among the metals and ions demonstrated that strong correlation existed between Al, Fe, Mg, K and Mn suggesting a common origin for these species i.e. the crustal mineral aerosols. The correlations among cations and anions implied the presence of compounds in the atmosphere such as CaSO4, (NH4)2SO4, KCl, KSO4, and also to some extent MgSO4. An investigation of ionic ratios revealed that ratios SO4-2/NO3-, Ca+2/K+, and Ca+2/Na+ could be possible indicators to identify scenarios industrial over residential locations, storm days over no storm days and summer over winter periods respectively.
Mostrar más [+] Menos [-]Micronucleus test in fishes as indicators of environmental quality in subestuaries of the Río de la Plata (Uruguay) Texto completo
2015
Gutiérrez, Juan Manuel | Villar, Silvia | Acuña Plavan, Alicia
Genotoxic agents may exert damage that may be active through following generations. Micronuclei are cytoplasmic chromatin masses outside the main cell nucleus, indicators of chromosomal damage. This study applied micronuclei test to evaluate genetic damage of fish in three breeding and nursery areas of commercially important fishes exposed to differing degrees of anthropogenic impact: Pando, Solís Chico and Solís Grande sub-estuaries. The micronuclei test revealed differences in the presence and concentrations of genotoxic components in these sub-estuaries. Fish in the urban and industrialized Pando sub-estuary presented the highest percentages of micronuclei. The absence of seasonal changes in micronuclei in Pando fish could be explained by physical characteristics of the sub-estuary and by regional weather conditions. Odontesthes argentinensis (Valenciennes, 1835) was the species most susceptible to genotoxic components. It is recommended the use of a battery of biomarkers to better explain the health of organisms in that important nursery area.
Mostrar más [+] Menos [-]Trophic structure in a pilot system for the integrated multi-trophic aquaculture off the east coast of Korean peninsula as determined by stable isotopes Texto completo
2015
Park, Hyun Je | Han, Eunah | Lee, Won-Chan | Kwak, Jung Hyun | Kim, Hyung-Chul | Park, Mi Seon | Kang, Chang-Keun
To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ13C and δ15N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment.
Mostrar más [+] Menos [-]Changes to the biomass and species composition of Ulva sp. on Porphyra aquaculture rafts, along the coastal radial sandbank of the Southern Yellow Sea Texto completo
2015
Huo, Yuanzi | Han, Hongbin | Shi, Honghua | Wu, Hailong | Zhang, Jianheng | Yu, Kefeng | Xu, Ren | Liu, Caicai | Zhang, Zhenglong | Liu, Kefu | He, Peimin | Ding, Dewen
Compositions, changes and biomass of attached Ulva species on Porphyra rafts along the radial sandbank in the Yellow Sea were investigated, and potential contributions to green tides was analyzed. Ulva prolifera, Ulva flexuosa and Ulva linza were all appeared throughout the investigated period. U. prolifera and U. flexuosa dominated attached Ulva population on Porphyra rafts. Attached Ulva species biomass showed obviously spatial and temporal variations. Temperature, Ulva microscopic propagules and human activities were main factors to influence attached Ulva species biomass. The total attached Ulva species biomass was more than 20,000 fresh weight tons in April, and the green tide causative species U. prolifera accounted 51.03% in April 2013 before green tides occurred. The high biomass of attached Ulva species would contribute most to green tides in the Yellow Sea. But how attached Ulva species on Porphyra rafts contributing to green tides in the Yellow Sea should be further studied.
Mostrar más [+] Menos [-]A review of the physical impacts of sediment dispersion from aggregate dredging Texto completo
2015
Spearman, Jeremy
The disturbance and subsequent dispersion of sediment arising from aggregate dredging results in increases in suspended sediment concentrations and, potentially, settlement of fine sediment or sand onto the bed, which may both cause adverse effects on local ecology. This subject is one area which has seen much research over many years and this paper sets out to synthesise some basic general conclusions for use when assessing the significance of planned operations. The literature detailing the dispersion of fine sediment plumes, and the longer term dispersion of sand released through the dredging process, is scrutinised, and in some cases re-evaluated, and used to identify an evidence-based footprint of potential impact.
Mostrar más [+] Menos [-]How Does Contamination of Rice Soils with Cd and Zn Cause High Incidence of Human Cd Disease in Subsistence Rice Farmers Texto completo
2015
Chaney, Rufus L.
Rice (Oryza sativa L.) grown on Zn mine waste contaminated soils has caused unequivocal Cd effects on kidney and occasional bone disease (itai-itai) in subsistence rice farmers, but high intake of Cd from other foods has not caused similar effects. Research has clarified two important topics about how Cd from mine waste contaminated rice soils has caused Cd disease: (1) bioaccumulation of soil Cd into rice grain without corresponding increase in Zn, and (2) subsistence rice diets potentiate Cd absorption/bioavailability and risk to farm families. Absorption of Cd by rice roots occurs on the NRAMP5 Mn²⁺ transporter. Although other transporters can influence Cd uptake-transport to shoots and grain, making NRAMP5 null greatly reduces grain Cd. Zn²⁺ has little ability to inhibit Cd²⁺ transfer in rice but clearly inhibits Cd uptake in other plant species. The bioavailability of dietary Cd is increased for subsistence rice diets. Research has identified that low levels and bioavailability of Zn and Fe in polished rice grain cause upregulation of Cd absorption on the Fe²⁺ transporter of duodenum cells (DMT1). Added dietary Zn can also inhibit intestinal Cd absorption somewhat. Nutritional stress (Fe, Zn deficiency) in humans consuming subsistence rice diets thus promotes Cd accumulation and adverse effects. No other dietary (crop) Cd exposure has caused unequivocal Cd-induced renal proximal tubular dysfunction (the first adverse Cd effect) in humans. Recognition of the very unusual nature of Cd risk from rice compared to other crops should be taken into account in setting international limits of Cd in rice and other foods.
Mostrar más [+] Menos [-]Occurence and antimicrobial resistance of Staphylococcus aureus and Salmonella spp. in retail fish samples in Turkey Texto completo
2015
Ertas Onmaz, Nurhan | Abay, Secil | Karadal, Fulden | Hizlisoy, Harun | Telli, Nihat | Al, Serhat
The aims of this study were to investigate the presence of Staphylococcus aureus and staphylococcal enterotoxins, as well as Salmonella spp. and to determine the antimicrobial susceptibilities of the isolates from fish samples. A total of 100 fish samples were analysed consisting of 30 anchovy, 35 trout and 35 sea bream. The presence of SEs was detected using ELISA and its genes confirmed by mPCR. Also, S. aureus and Salmonella spp. were detected in 9 (9%) and 5 (5%) samples, respectively. None of the S. aureus isolates had SEs and SEs genes. The resistance rates of the S. aureus isolates to erythromycin, tetracycline, and penicillin G were found to be 33% while Salmonella spp. isolates were resistant to trimethoprim-sulfamethoxazole, gentamicin and neomycine in 20%, 20% and 80%, respectively of the samples. It is of utmost important for public health that retail fish markets need to use hygienic practices in handling and processing operations.
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