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Exceptionally high Cd levels and other trace elements in eggshells of American oystercatcher (Haematopus palliatus) from the Bahía Blanca Estuary, Argentina Full text
2015
Simonetti, Pía | Botté, Sandra Elizabeth | Marcovecchio, Jorge Eduardo
Exceptionally high Cd levels and other trace elements in eggshells of American oystercatcher (Haematopus palliatus) from the Bahía Blanca Estuary, Argentina Full text
2015
Simonetti, Pía | Botté, Sandra Elizabeth | Marcovecchio, Jorge Eduardo
Concentrations of six trace metals were determined in the eggshells of American oystercatchers (Haematopus palliatus) from the Bahía Blanca estuary, Argentina. All metals measured in selected samples presented concentrations above the detection limit. Means found for Cu, Pb, Cr, Zn and Ni were as follow: 2.02±0.52, 7.23±2.33, 0.78±0.03, 2.22±1.13 and 6.05±0.89mg/kg dw. The mean concentrations of Cd found were surprisingly high: 13.28±3.38mg/kg dw. Previous studies made on prey items of the American oystercatchers showed low to medium concentrations of the six trace metals. This may indicate a possible transfer of the metals that are available in the environment through food chains. Our study indicates that American oystercatchers sequester heavy metals in their eggshells. Therefore the eggshells may be useful as biomonitors for trace metal contamination in the Bahía Blanca estuary.
Show more [+] Less [-]Exceptionally high Cd levels and other trace elements in eggshells of American oystercatcher (Haematopus palliatus) from the Bahía Blanca Estuary, Argentina Full text
2015
Simonetti, Pia | Botté, Sandra Elizabeth | Marcovecchio, Jorge Eduardo
Concentrations of six trace metals were determined in the eggshells of American oystercatchers (Haematopus palliatus) from the Bahía Blanca estuary, Argentina. All metals measured in selected samples presented concentrations above the detection limit. Means found for Cu, Pb, Cr, Zn and Ni were as follow: 2.02 ± 0.52, 7.23 ± 2.33, 0.78 ± 0.03, 2.22 ± 1.13 and 6.05 ± 0.89 mg/kg dw. The mean concentrations of Cd found were surprisingly high: 13.28 ± 3.38 mg/kg dw. Previous studies made on prey items of the American oystercatchers showed low to medium concentrations of the six trace metals. This may indicate a possible transfer of the metals that are available in the environment through food chains. Our study indicates that American oystercatchers sequester heavy metals in their eggshells. Therefore the eggshells may be useful as biomonitors for trace metal contamination in the Bahía Blanca estuary. | Fil: Simonetti, Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina | Fil: Botté, Sandra Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina | Fil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto Argentino de Oceanografía (i); Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Universidad FASTA "Santo Tomas de Aquino"; Argentina
Show more [+] Less [-]Meteorological driven changes on air quality over Portugal: a KZ filter application Full text
2015
Sá, Elisa | Tchepel, Oxana | Carvalho, Anabela | Borrego, C.
Meteorological driven changes on air quality over Portugal: a KZ filter application Full text
2015
Sá, Elisa | Tchepel, Oxana | Carvalho, Anabela | Borrego, C.
The Kolmogorov–Zurbenko (KZ) filter method is a tool to improve air quality management, since it determines meteorological effects on air quality concentrations and separates out those effects in order to examine underlying trends. Air quality in Portugal is exceeding the legislated particulate matter (PM10), nitrogen oxides (NO2) and ozone (O3) levels; accordingly, measures to reduce pollutant emissions have been designed. The primary objective of this work is to investigate the influence of meteorology on O3, NO2 and PM10 levels and the long-term air quality trends. Air quality and meteorological datasets were explored for the period 2002–2012 through the decomposition of time-series using the Kolmogorov–Zurbenko (KZ) filter. To determine the best meteorological predictors for the air quality data, a stepwise regression analysis of the filtered time-series was applied. The KZ filter application revealed that the short-term component has the highest contribution to the total variance of the original air quality data (≈64%–PM10; ≈52%–O3; ≈54%–NO2) followed by the seasonal component. The long-term component exhibits the influence of the emission control regulations implemented in each study region. The statistical analysis of the air quality and the meteorological data indicated that O3 has a statistically significant relationship with temperature in most of the components. The results also indicate that emission control strategies are primary regulators for NO2 and PM10 levels. Therefore, to establish an accurate strategy to improve air quality further, it will be essential to include meteorological effects. This study highlights that the KZ filter is a useful tool to support the design and implementation of adequate air quality strategies and for the investigation of the interactions between the emissions, the meteorological conditions and the air quality levels, to improve air quality management in these two urban areas.
Show more [+] Less [-]Meteorological driven changes on air quality over Portugal: a KZ filter application Full text
2015 | 1000
Sa, Elisa | Tchepel, Oxana | Carvalho, Anabela | Borrego, Carlos
The KolmogoroveZurbenko (KZ) filter method is a tool to improve air quality management, since it determines meteorological effects on air quality concentrations and separates out those effects in order to examine underlying trends. Air quality in Portugal is exceeding the legislated particulate matter (PM10), nitrogen oxides (NO2) and ozone (O3) levels; accordingly, measures to reduce pollutant emissions have been designed. The primary objective of this work is to investigate the influence of meteorology on O3, NO2 and PM10 levels and the long-term air quality trends. Air quality and meteorological datasets were explored for the period 2002e2012 through the decomposition of time-series using the KolmogoroveZurbenko (KZ) filter. To determine the best meteorological predictors for the air quality data, a stepwise regression analysis of the filtered time-series was applied. The KZ filter application revealed that the short-term component has the highest contribution to the total variance of the original air quality data (z64%ePM10; z52%eO3; z54%eNO2) followed by the seasonal component. The longterm component exhibits the influence of the emission control regulations implemented in each study region. The statistical analysis of the air quality and the meteorological data indicated that O3 has a statistically significant relationship with temperature in most of the components. The results also indicate that emission control strategies are primary regulators for NO2 and PM10 levels. Therefore, to establish an accurate strategy to improve air quality further, it will be essential to include meteorological effects. This study highlights that the KZ filter is a useful tool to support the design and implementation of adequate air quality strategies and for the investigation of the interactions between the emissions, the meteorological conditions and the air quality levels, to improve air quality management in these two urban areas.
Show more [+] Less [-]Sample port design for ballast water sampling: Refinement of guidance regarding the isokinetic diameter Full text
2015
Wier, Timothy P. | Moser, Cameron S. | Grant, Jonathan F. | First, Matthew R. | Riley, Scott C. | Robbins-Wamsley, Stephanie H. | Drake, Lisa A.
By using an appropriate in-line sampling system, it is possible to obtain representative samples of ballast water from the main ballast line. An important parameter of the sampling port is its “isokinetic diameter” (DISO), which is the diameter calculated to determine the velocity of water in the sample port relative to the velocity of the water in the main ballast line. The guidance in the U.S. Environmental Technology Verification (ETV) program protocol suggests increasing the diameter from 1.0× DISO (in which velocity in the sample port is equivalent to velocity in the main line) to 1.5–2.0× DISO. In this manner, flow velocity is slowed—and mortality of organisms is theoretically minimized—as water enters the sample port. This report describes field and laboratory trials, as well as computational fluid dynamics modeling, to refine this guidance. From this work, a DISO of 1.0–2.0× (smaller diameter sample ports) is recommended.
Show more [+] Less [-]Water protection in the Baltic Sea and the Chesapeake Bay: Institutions, policies and efficiency Full text
2015
Iho, Antti | Ribaudo, Marc | Hyytiäinen, Kari
Water protection in the Baltic Sea and the Chesapeake Bay: Institutions, policies and efficiency Full text
2015
Iho, Antti | Ribaudo, Marc | Hyytiäinen, Kari
The Baltic Sea and the Chesapeake Bay share many characteristics. Both are shallow, brackish marine areas that suffer from eutrophication. Successful policies targeting point source pollution have lowered nutrient loads in both areas, but achieving the desired marine quality will require further abatement: efforts may be extended to more complicated and expensive pollution sources, notably agricultural nonpoint loads. Despite their ecological similarities, the two watersheds have different histories and institutional settings and have thus adopted different policies. Comparing and contrasting the policies reveal ways to improve the efficiency of each and ways to avoid the path of trial and error. No comparison of the parallel protection efforts, which involve expenditures of hundreds of millions of dollars annually, has been carried out to date. The present paper analyzes the policies applied in the two regions, distilling the results into six recommendations for future steps in preserving what are valuable sea areas.
Show more [+] Less [-]Water protection in the Baltic Sea and the Chesapeake Bay : institutions, policies and efficiency Full text
2015
Iho, Antti | Ribaudo, Marc | Hyytiäinen, Kari | Luke / Talous ja yhteiskunta / Luonnonvarojen hyödyntäminen / Ympäristötalous (400403) | 400403
The Baltic Sea and the Chesapeake Bay share many characteristics. Both are shallow, brackish marine areas that suffer from eutrophication. Successful policies targeting point source pollution have lowered nutrient loads in both areas, but achieving the desired marine quality will require further abatement: efforts may be extended to more complicated and expensive pollution sources, notably agricultural nonpoint loads. Despite their ecological similarities, the two watersheds have different histories and institutional settings and have thus adopted different policies. Comparing and contrasting the policies reveal ways to improve the efficiency of each and ways to avoid the path of trial and error. No comparison of the parallel protection efforts, which involve expenditures of hundreds of millions of dol- lars annually, has been carried out to date. The present paper analyzes the policies applied in the two regions, distilling the results into six recommendations for future steps in preserving what are valuable sea areas | 2015
Show more [+] Less [-]What did we learn from PEGASEAS forum “Science and Governance of the Channel Marine Ecosystem”? Full text
2015
Evariste, Emmanuelle | Claquin, Pascal | Robin, Jean-Paul | Auber, Arnaud | McQuatters-Gollop, Abigail | Fletcher, Stephen | Glegg, Gillian | Dauvin, Jean-Claude
What did we learn from PEGASEAS forum “Science and Governance of the Channel Marine Ecosystem”? Full text
2015
Evariste, Emmanuelle | Claquin, Pascal | Robin, Jean-Paul | Auber, Arnaud | McQuatters-Gollop, Abigail | Fletcher, Stephen | Glegg, Gillian | Dauvin, Jean-Claude
As one of the busiest marine ecosystems in the world, the English Channel is subjected to strong pressures due to the human activities occurring within it. Effective governance is required to improve the combined management of different activities and so secure the benefits provided by the Channel ecosystem. In July 2014, a Cross-Channel Forum, entitled “Science and Governance of the Channel Marine Ecosystem”, was held in Caen (France) as part of the INTERREG project “Promoting Effective Governance of the Channel Ecosystem” (PEGASEAS). Here we use outputs from the Forum as a framework for providing Channel-specific advice and recommendations on marine governance themes, including the identification of knowledge gaps, which may form the foundation of future projects for the next INTERREG project call (2015–2020).
Show more [+] Less [-]What did we learn from PEGASEAS forum “Science and Governance of the Channel Marine Ecosystem”? Full text
2015
Evariste, Emmanuelle | Claquin, Pascal | Robin, Jean-pierre | Auber, Arnaud | Mcquatters-gollop, Abigail | Fletcher, Stephen | Glegg, Gillian | Dauvin, Jean-claude
As one of the busiest marine ecosystems in the world, the English Channel is subjected to strong pressures due to the human activities occurring within it. Effective governance is required to improve the combined management of different activities and so secure the benefits provided by the Channel ecosystem. In July 2014, a Cross-Channel Forum, entitled “Science and Governance of the Channel Marine Ecosystem”, was held in Caen (France) as part of the INTERREG project “Promoting Effective Governance of the Channel Ecosystem” (PEGASEAS). Here we use outputs from the Forum as a framework for providing Channel-specific advice and recommendations on marine governance themes, including the identification of knowledge gaps, which may form the foundation of future projects for the next INTERREG project call (2015–2020).
Show more [+] Less [-]Spatial variation, fractionation and sedimentary records of mercury in the East China Sea Full text
2015
Duan, Li-Qin | Song, Jin-Ming | Yu, Yu | Yuan, Hua-Mao | Li, Xue-Gang | Li, Ning
Surface and core sediments were collected to study distributions, phases and potential environmental risk of Hg and to reconstruct anthropogenic Hg change over the past one hundred years in the East China Sea (ECS). Hg contents in surface sediments displayed a decreasing gradient from the Changjiang Estuary to the outer sea. Sequential extraction analysis showed that Hg mainly existed as residual fraction (70.18% of total), and while organic matter fraction (22.96% of total) was the main component of labile fraction, indicating the strong adsorption of organic matters on Hg. Enrichment factor and sediment quality guidelines suggested that Hg in sediments of ECS were at minor enrichment and low adverse effect. Temporal distributions of total Hg content, labile fraction, burial flux and anthropogenic Hg flux showed that anthropogenic Hg input increased since the 1960s, which was related to riverine input and atmospheric transport.
Show more [+] Less [-]Assessing the viability of microorganisms in the ballast water of vessels transiting the North Atlantic Ocean Full text
2015
Steichen, Jamie L. | Quigg, Antonietta
Testing phytoplankton viability within ballast tanks and receiving waters of ballast water discharge remain understudied. Potentially harmful dinoflagellates and diatoms are transported via ballast water to Galveston Bay, Texas (USA), home to three major ports: Houston, Texas City and Galveston. Ballast water from vessels transiting the North Atlantic Ocean was inoculated into treatments representing low and high salinity conditions similar to the Ports of Houston and Galveston respectively. Phytoplankton in ballast water growout experiments were deemed viable and showed growth in low and mid salinities with nutrient enrichment. Molecular methods identified several genera: Dinophysis, Gymnodinium, Gyrodinium, Heterocapsa, Peridinium, Scrippsiella, Chaetoceros and Nitzschia. These phytoplankton genera were previously identified in Galveston Bay except Scrippsiella. Phytoplankton, including those capable of forming harmful algal blooms leading to fish and shellfish kills, are transported to Galveston Bay via ballast water, and are viable when introduced to similar salinity conditions found in Galveston Bay ports.
Show more [+] Less [-]Studies on polycyclic aromatic hydrocarbons in surface sediments of Mithi River near Mumbai, India: Assessment of sources, toxicity risk and biological impact Full text
2015
Singare, Pravin U.
This study investigated the levels, sources and potential risks of 17 polycyclic aromatic hydrocarbons in surface sediment samples collected along the Mithi River of Mumbai. The concentration level of ΣPAHs found in the present study was in the range of 1206–4735ng/gdw. The composition patterns of PAHs by ring size in sediment were surveyed which indicate the dominance of four rings followed by five and three ring PAHs. In the study it was observed that the high molecular weight PAHs (HMW PAHs) made greater contributions of 90.83% as compared to that of low molecular PAHs (LMW PAHs) contributing to 9.17% to the total PAH concentrations. Toxicity and biological risk were assessed using toxic equivalent quantity and sediment quality guideline quotient. It is feared that the pollution level of PAHs in the sediments might increase in coming times resulting in an unconspicuous risks for the environment and humans through food chains.
Show more [+] Less [-]Characterizing the parent and oxygenated polycyclic aromatic hydrocarbons in mangrove sediments of Hong Kong Full text
2015
Wang, Xiaowei | Yuan, Ke | Yang, Lihua | Lin, Li | Tam, Nora F.Y. | Chen, Baowei | Luan, Tiangang
Parent and oxygenated polycyclic aromatic hydrocarbons (PAHs) were investigated in mangrove sediments of Hong Kong. Most of the analytes were detected, and the dominant carbonylic and hydroxylated PAHs in mangrove sediments were 9-fluorenone and 2-hydroxy fluorene, respectively. The concentration of 9-fluorenone and 9,10-anthraquinone was higher than their parent PAHs. Moreover, the concentration of total organic matter (TOM) related with those of the parent PAHs and carbonylic PAHs, except for hydroxylated PAHs, which indicated that TOM was not the only factor regulating the distribution of oxygenated PAHs. Nevertheless, the parent PAHs in mangrove sediments was correlated positively with carbonylic PAHs which demostrated not only the similar source but also the fate of these two compound class. However, hydroxylated PAHs had different source by comparing with parent PAHs and carbonylic PAHs, they were probably originated from biodegradation and accumulated in mangrove sediments.
Show more [+] Less [-]First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea Full text
2015
Romeo, Teresa | Pietro, Battaglia | Pedà, Cristina | Consoli, Pierpaolo | Andaloro, Franco | Fossi, Maria Cristina
This study focuses, for the first time, on the presence of plastic debris in the stomach contents of large pelagic fish (Xiphias gladius, Thunnus thynnus and Thunnus alalunga) caught in the Mediterranean Sea between 2012 and 2013. Results highlighted the ingestion of plastics in the 18.2% of samples. The plastics ingested were microplastics (<5mm), mesoplastics (5–25mm) and macroplastics (>25mm).These preliminary results represent an important initial phase in exploring two main ecotoxicological aspects: (a) the assessment of the presence and impact of plastic debris on these large pelagic fish, and (b) the potential effects related to the transfer of contaminants on human health.
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