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The significance of cephalopod beaks in marine ecology studies: Can we use beaks for DNA analyses and mercury contamination assessment? Full text
2016
Xavier, José Carlos | Ferreira, Sônia | Tavares, Sílvia | Santos, Nuno | Mieiro, Cláudia Leopoldina | Trathan, Phil N. | Lourenço, Silvia | Martinho, Filipe | Steinke, Dirk | Seco, José | Pereira, Eduarda | Pardal, Miguel | Cherel, Yves
The significance of cephalopod beaks in marine ecology studies: Can we use beaks for DNA analyses and mercury contamination assessment? Full text
2016
Xavier, José Carlos | Ferreira, Sônia | Tavares, Sílvia | Santos, Nuno | Mieiro, Cláudia Leopoldina | Trathan, Phil N. | Lourenço, Silvia | Martinho, Filipe | Steinke, Dirk | Seco, José | Pereira, Eduarda | Pardal, Miguel | Cherel, Yves
Cephalopod beaks found in the diet of predators have been a major source of scientific information. In this study, we evaluated the usefulness of DNA and contaminants analysis (total mercury — T-Hg) in cephalopod beaks in order to assess their applicability as tools in marine ecology studies. We concluded that, when applying DNA techniques to cephalopod beaks from Antarctic squid species, when using flesh attached to those beaks, it was possible to obtain DNA and to successfully identify cephalopod species; DNA was not found on the beaks themselves. This study also showed that it is possible to obtain information on T-Hg concentrations in beaks: the T-Hg concentrations found in the beaks were 6 to 46 times lower than in the flesh of the same cephalopod species. More research on the relationships of mercury concentrations in cephalopod beaks (and other tissues), intra- and inter-specifically, are needed in the future.
Show more [+] Less [-]Can we use beaks for DNA analyses and mercury contamination assessment? Full text
2016
Xavier, José Carlos | Ferreira, Sónia | Tavares, Silvia | Santos, Nuno | Mieiro, Cláudia Leopoldina | Trathan, Philip N. | Lourenço, Sílvia | Martinho, Filipe | Steinke, Dirk | Seco, Jose | Pereira, Eduarda | Pardal, Miguel | Cherel, Yves | British Antarctic Survey (BAS) ; Natural Environment Research Council (NERC) | Biodiversity institute of Ontario ; University of Guelph [Guelf, Ontario, Canada] | Marine and environmental research centre - IMAR-CMA (Coimbra, Portugal) ; Universidade de Coimbra = University of Coimbra [Portugal] (UC) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)
International audience | Cephalopod beaks found in the diet of predators have been amajor source of scientific information. In this study,we evaluated the usefulness of DNA and contaminants analysis (total mercury — T-Hg) in cephalopod beaks inorder to assess their applicability as tools in marine ecology studies. We concluded that, when applying DNAtechniques to cephalopod beaks from Antarctic squid species, when using flesh attached to those beaks, it waspossible to obtain DNA and to successfully identify cephalopod species; DNA was not found on the beaks themselves.This study also showed that it is possible to obtain information on T-Hg concentrations in beaks: the T-Hgconcentrations found in the beaks were 6 to 46 times lower than in the flesh of the same cephalopod species.More research on the relationships of mercury concentrations in cephalopod beaks (and other tissues), intraandinter-specifically, are needed in the future.
Show more [+] Less [-]Behavior of suspended particles in the Changjiang Estuary: Size distribution and trace metal contamination Full text
2016
Yao, Qingzhen | Wang, Xiaojing | Jian, Huimin | Chen, Hongtao | Yu, Zhigang
Suspended particulate matter (SPM) samples were collected along a salinity gradient in the Changjiang Estuary in June 2011. A custom-built water elutriation apparatus was used to separate the suspended sediments into five size fractions. The results indicated that Cr and Pb originated from natural weathering processes, whereas Cu, Zn, and Cd originated from other sources. The distribution of most trace metals in different particle sizes increased with decreasing particle size. The contents of Fe/Mn and organic matter were confirmed to play an important role in increasing the level of heavy metal contents. The Cu, Pb, Zn, and Cd contents varied significantly with increasing salinity in the medium–low salinity region, thus indicating the release of Cu, Pb, Zn, and Cd particles. Thus, the transfer of polluted fine particles into the open sea is probably accompanied by release of pollutants into the dissolved compartment, thereby amplifying the potential harmful effects to marine organisms.
Show more [+] Less [-]Plastic ingestion by a generalist seabird on the coast of Uruguay Full text
2016
Lenzi, Javier | Burgues, María Fernanda | Carrizo, Daniel | Machín, Emanuel | Teixeira-de Mello, Franco
We analyzed plastic ingestion by Kelp Gull (Larus dominicanus) from 806 pellets collected between 2011 and 2013. Employing a Raman spectroscopy, we characterized those polymers used to produce the plastics ingested. Debris was recorded in 143 pellets (%FO=17.7%, n=202, 92.58g). Plastic was found in 119 pellets (%FO=83%) and non-plastic occurred in 56 pellets (%FO=39%). The most important debris category was plastic film with 55.3% (n=79). Plastic bags were observed in 19 pellets (%FO=2.4%, weight=25.02g). Glass was the second most important component (%FO=18.9%) followed by plastic fragments (%FO=17.8%). Plastic debris represented the 65.3% of the debris fragments (n=132, weight=58.84g), and was composed by polyethylene (52%), polypropylene (26%), polyamide (12%), polystyrene (6%), polyvinyl chloride (2%), and polyethylene terephthalate (2%). How plastics were obtained by gulls and the effects on individuals are discussed, as well as environmental considerations about plastic pollution on coastal environments.
Show more [+] Less [-]Barcodes of marine invertebrates from north Iberian ports: Native diversity and resistance to biological invasions Full text
2016
Miralles, L. | Ardura, A. | Arias, A. | Borrell, Y.J. | Clusa, L. | Dopico, E. | de Rojas, A Hernandez | López, B. | Muñoz-Colmenero, M. | Roca, A. | Valiente, A.G. | Zaiko, A. | Garcia-Vazquez, E.
Barcodes of marine invertebrates from north Iberian ports: Native diversity and resistance to biological invasions Full text
2016
Miralles, L. | Ardura, A. | Arias, A. | Borrell, Y.J. | Clusa, L. | Dopico, E. | de Rojas, A Hernandez | López, B. | Muñoz-Colmenero, M. | Roca, A. | Valiente, A.G. | Zaiko, A. | Garcia-Vazquez, E.
Ports are gateways for many marine organisms transported by ships worldwide, especially non-indigenous species (NIS). In this study carried out in North Iberian ports (Cantabrian Sea, Bay of Biscay) we have observed 38% of exotic macroinvertebrates. Four species, namely the barnacle Austrominius modestus, the tubeworm Ficopomatus enigmaticus, the Pacific oyster Crassostrea gigas and the pygmy mussel Xenostrobus securis, exhibited clear signs of invasiveness. A total of 671 barcode (cytochrome oxidase subunit I or 18S rRNA) genes were obtained and confirmed the species status of some cryptic NIS. Negative and significant correlation between diversity estimators of native biota and proportion of NIS suggests biotic resistance in ports. This could be applied to management of port biota for contributing to prevent the settlement of biopollutants in these areas which are very sensitive to biological invasions.
Show more [+] Less [-]Barcodes of marine invertebrates from north Iberian ports: Native diversity and resistance to biological invasions Full text
2016
Miralles, L. | Arias, A. | Borrell, Yaisel Juan | Clusa, L. | Hernández-de-Rojas, Alma | Muñoz-Colmenero, M. | Valiente, A.G. | Zaiko, A. | García-Vázquez, E.
Ports are gateways for many marine organisms transported by ships worldwide, especially non-indigenous species (NIS). In this study carried out in North Iberian ports (Cantabrian Sea, Bay of Biscay) we have observed 38% of exotic macroinvertebrates. Four species, namely the barnacle Austrominius modestus, the tubeworm Ficopomatus enigmaticus, the Pacific oyster Crassostrea gigas and the pygmy mussel Xenostrobus securis, exhibited clear signs of invasiveness. A total of 671 barcode (cytochrome oxidase subunit I or 18S rRNA) genes were obtained and confirmed the species status of some cryptic NIS. Negative and significant correlation between diversity estimators of native biota and proportion of NIS suggests biotic resistance in ports. This could be applied to management of port biota for contributing to prevent the settlement of biopollutants in these areas which are very sensitive to biological invasions. | SI
Show more [+] Less [-]Estimating the input of submarine groundwater discharge (SGD) and SGD-derived nutrients in Geoje Bay, Korea using 222Rn-Si mass balance model Full text
2016
Hwang, Dong-Woon | Lee, In-Seok | Choi, Minkyu | Kim, Tae-Hoon
In order to evaluate the main source of nutrients for maintaining the high production in shellfish farming bay, we have measured 222Rn activities and the concentrations of nutrients in stream water, seawater, and coastal groundwater around Geoje Bay, one of the largest cultivation areas of oyster in the southern sea of Korea in April 2013. Using the 222Rn and Si mass balance model, the residence time of bay seawater was about 5days and the submarine groundwater discharge (SGD) into the bay was estimated to be approximately 1.8×106m3 d−1. The SGD-derived nutrient fluxes contributed approximately 54% for DIN, 5% for DIP, and 50% for DSi of total nutrient input entering into the bay. Thus, our results suggest that SGD is the major source of nutrients in Geoje Bay, and SGD-derived nutrients are very important to support the biological production of this shellfish farming bay.
Show more [+] Less [-]Dynamic fugacity model for accidental oil release during Arctic shipping Full text
2016
Afenyo, Mawuli | K̲h̲ān, Faiṣal | Veitch, Brian | Yang, Ming
Improved understanding of ecological risk associated with Arctic shipping would help advance effective oil spill prevention, control, and mitigation strategies. Ecological risk assessment involves analysis of a release (oil), its fate, and dispersion, and the exposure and intake of the contaminant to different receptors. Exposure analysis is a key step of the detailed ecological risk assessment, which involves the evaluation of the concentration and persistence of released pollutants in the media of contact. In the present study, a multimedia fate and transport model is presented, which is developed using a fugacity-based approach. This model considers four media: air, water, sediment, and ice. The output of the model is the concentration of oil (surrogate hydrocarbons-naphthalene) in these four media, which constitutes the potential exposure to receptors. The concentration profiles can subsequently be used to estimate ecological risk thereby providing guidance to policies for Arctic shipping operations, ship design, and ecological response measures.
Show more [+] Less [-]Chemical composition of floating and sunken in-situ burn residues from the Deepwater Horizon oil spill Full text
2016
Stout, Scott A. | Payne, James R.
In-situ burning during the Deepwater Horizon oil spill generated tens of thousands of barrels of in-situ burn (ISB) residues in the northern Gulf of Mexico (GoM), most or all of which eventually sank to the seafloor. Chemical analyses showed that floating and sunken (~1400m deep) ISB residues (1) exhibited distinct n-alkanes and UCM profiles inconsistent with vapor-pressure driven evaporation, (2) were relatively enriched in pyrogenic PAHs, particularly less stable (mostly) linear PAH isomers formed during burning, and (3) had lost petroleum biomarkers, relative to their volatility. PAH concentrations in ISB residues indicate that between 26,800 and 37,800kg of total PAHs (TPAH51) and 2880 and 4060kg of 16 Priority Pollutant PAHs were potentially deposited on the seafloor in discrete ISB residue particles. Despite this additional benthic impact, ISB reduced the total mass loadings of PAH from the burned oil to the GoM by 89% (ignoring any re-deposition from atmospheric emissions).
Show more [+] Less [-]Analysis of the TSP, PM10 concentrations and water-soluble ionic species in airborne samples over Sistan, Iran during the summer dusty period Full text
2016
Dahmardeh Behrooz, Reza | Esmaili-Sari, Abbas | Bahramifar, Nader | Kaskaoutis, D.G.
The present study analyzes the total suspended particulates (TSP) and particulate matter less than 10 μm (PM10) concentrations along with the water-soluble ionic species (WSIS) in airborne dust samples collected in Zabol, located in the Sistan basin of southeast Iran. Rather extreme TSP and PM10 mean concentrations of 1867.0 μg m−3 and 433.4 μg m−3 are found, while the WSIS contribute only 8.9% and 19.3% to the TSP and PM10 mass, respectively indicating large fraction of water-insoluble crustal elements, carbonaceous aerosols and heavy metals that remained unexplored. Ca2+ is the most abundant ionic species contributing ∼25–26% to the total WSIS mass, followed by NH4+, K+, and SO42−. Important fractions of Cl− and Na+ (7–9% of the total WSIS mass) indicate the presence of saline dust storms over Sistan due to desiccation of the Hamoun lakes and uplift of evaporated minerals by the strong Levar (120-days) wind. High correlations between the WSIS suggest large possibility for formation of NaCl, (NH4)2SO4, MgSO4, K2SO4, CaSO4 and NH4NO3. The dusty days (visibility < 2 km) are associated with intense winds (11.7 ms−1 on average) and large increase (∼80–100%) in the concentrations of the crustal elements (e.g., Ca2+, Mg2+ and Cl−) compared to the normal days, while the TSP and PM10 concentrations reach to 4496 μgm−3 and 1010.6 μgm−3, respectively.
Show more [+] Less [-]Long-term weathering and continued oxidation of oil residues from the Deepwater Horizon spill Full text
2016
White, Helen K. | Wang, Chloe H. | Williams, Patrick L. | Findley, David M. | Thurston, Alana M. | Simister, Rachel L. | Aeppli, Christoph | Nelson, Robert K. | Reddy, Christopher M.
To investigate the long-term weathering of oil from the Deepwater Horizon (DWH) incident, oil-soaked sand patties were collected from Gulf of Mexico beaches from Florida to Alabama over a three-year period from 2012 to 2014. Analysis of oil residues by gas chromatography with flame ionization detection (GC-FID), thin-layer chromatography with flame ionization detection (TLC-FID), and Fourier transform infrared spectroscopy (FT-IR) indicated uniformity in their chemical composition. Some variability within and between samples was observed, arising from differences in exposure to light and water, which increase the amount of weathering. Oxygenated hydrocarbons (OxHC) produced by weathering processes dominate the majority of oil residues. These OxHC have continued recalcitrance in the environment, and increase in relative abundance over time. Analyses of the bulk characteristics of oil residues via TLC-FID and FT-IR should be continued as these techniques provide important insight into the weathering state of oil residues.
Show more [+] Less [-]Polycyclic aromatic hydrocarbons in surface sediments from the Coast of Weihai, China: Spatial distribution, sources and ecotoxicological risks Full text
2016
Zhang, Daolai | Liu, Jinqing | Yin, Ping | Lin, Xuehui | Liu, Na | Meng, Xianwei
This study was conducted to measure the polycyclic aromatic hydrocarbon (PAH) concentrations and evaluate the distribution, sources in surface sediments from various coastal sites in Weihai, which create good conditions for rapid development because of their excellent geographical location and abundant marine resources. The results indicated that the total PAHs contents in the sediments of Weihai ranged from 2.69 to 166.50ngg−1, with an average of 67.44ngg−1. Phenanthrene, Fluoranthene, Benzo(b)fluoranthene, Chrysene, and Pyrene were dominant in sediments, primarily as a result of high temperature combustion and biomass. Molecular ratios suggested that these PAHs in the sediments of Weihai were predominantly from pyrogenic sources such as grass, wood and charcoal combustion, as well as engine exhaust which is similar to the result of the study of the Yellow River Delta, China. The result of probability risk assessment additionally elucidated low PAH ecological risk in the surface sediments of Weihai, China.
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