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Optimizing oil spill cleanup efforts: A tactical approach and evaluation framework Texte intégral
2017
Grubesic, Tony H. | Wei, Ran | Nelson, Jake
Although anthropogenic oil spills vary in size, duration and severity, their broad impacts on complex social, economic and ecological systems can be significant. Questions pertaining to the operational challenges associated with the tactical allocation of human resources, cleanup equipment and supplies to areas impacted by a large spill are particularly salient when developing mitigation strategies for extreme oiling events. The purpose of this paper is to illustrate the application of advanced oil spill modeling techniques in combination with a developed mathematical model to spatially optimize the allocation of response crews and equipment for cleaning up an offshore oil spill. The results suggest that the detailed simulations and optimization model are a good first step in allowing both communities and emergency responders to proactively plan for extreme oiling events and develop response strategies that minimize the impacts of spills.
Afficher plus [+] Moins [-]Analysis and occurrence of some phenol endocrine disruptors in two marine sites of the northern coast of Sicily (Italy) Texte intégral
2017
Errico, Sonia | Nicolucci, Carla | Migliaccio, Marina | Micale, Valeria | Mita, Damiano G. | Diano, Nadia
This study reports the occurrence of some endocrine disrupting chemicals in red mullet samples and sediments collected in two representative sites of the northern Sicilian coast (Italy). For this purpose, an improved method, using solid extraction and high-performance liquid chromatography analyses for the simultaneous determination of bisphenol A (BPA), 4-nonylphenol (4-NP) and 4-t-octylphenol (4-t-OP) in fish tissues and sediments, has been developed and validated. Method performance was demonstrated over the concentration range 0.1–200ng/mL, with detection limits from 0.06 to 0.1ng/mL. Recoveries ranged from 83.4% to 102.6%, with relative standard deviations of 7.7–14.0% for the entire procedure.Results showed that BPA, 4-t-OP and 4-NP were detected in all fish samples and sediments from two sampling sites, indicating that these chemicals have contaminated Mediterranean aquatic ecosystem and have accumulated in fish. The study provided more comprehensive fundamental data for risk assessment and contamination control of phenolic EDCs in aquatic environment.
Afficher plus [+] Moins [-]Fusion of multi-source near-surface CO2 concentration data based on high accuracy surface modeling Texte intégral
2017
Mingwei, Zhao | Tianxiang, Yue | Xingying, Zhang | Jinglu, Sun | Ling, Jiang | Chun, Wang
Under the background of growing greenhouse gas emissions and the resulting global warming, researches about the spatial-temporal variation analysis of the concentration of carbon dioxide in the regional and global scale has become one of the most important topics in the scientific community. Simulating and analyzing the spatial-temporal variation of the carbon dioxide concentration on a global scale under limited observation data has become one of the key problems to be solved in the research field of spatial analysis technology. A new research approach based on high accuracy surface modeling data fusion (HASM-DF) method was proposed in this paper, in which the output of the CO2 concentration of the GEOS-Chem model were taken as driving field, and the observation values of CO2 concentration at ground observation station were taken as accuracy control conditions. The new approach's objective is to fulfill the fusion of the two kinds of CO2 data, and obtain the distribution of CO2 on a global scale with a higher accuracy than the results of GEOS-Chem. Root mean square error (RMSE) was chosen as the basic accuracy index, and the experimental analysis shows that the RMSE of the result of the proposed approach is 1.886 ppm, which is significantly lower than that of the GEOS-Chem's 2.239 ppm. Furthermore, compared with the results created by the interpolation methods used the observation values at stations; the fusion results keep a good spatial heterogeneity similar to the results of GEOS-Chem. This research analyzed the spatial distribution and time series variation of the near-surface CO2 based on the fusion result on a global scale. And it can found that areas such as East Asia, Western North American, Central South America and Central Africa and other region show a relatively high value of the near-surface CO2 concentration. And we also found that the near-surface CO2 concentration changes with season, especially in North America and Eurasia, the near-surface CO2 in summer was significantly lower than winter in these areas.
Afficher plus [+] Moins [-]Influence of environmental factors on the toxin production of Ostreopsis cf. ovata during bloom events Texte intégral
2017
Accoroni, Stefano | Tartaglione, Luciana | Dello Iacovo, Emma | Pichierri, Salvatore | Marini, Mauro | Campanelli, Alessandra | Dell'Aversano, Carmela | Totti, Cecilia
Intense blooms of the toxic dinoflagellate Ostreopsis have been a recurrent phenomenon along several Mediterranean coasts. Blooms have been associated with noxious effects on human health and mortality of marine organisms, due to the production of palytoxin-like compounds. We analyzed the toxin concentrations throughout an O. cf. ovata bloom to highlight their relationships with environmental parameters in the Conero Riviera, northern Adriatic Sea. High temperature and balanced nutrient conditions were the optimal environmental conditions to start and sustain blooms as well as to maximize toxin production. Ostreopsis showed a gradual decrease of toxin content throughout the bloom ascribed to the occurring of the same non-optimal conditions that led to the bloom decline. Moreover, our results suggest that toxin fraction released during bloom could be higher than that released in batch culture. Results from this study pointed out that the first bloom phase is potentially the most dangerous to human health.
Afficher plus [+] Moins [-]Distribution and source of organic matter in surface sediment from the muddy deposit along the Zhejiang coast, East China Sea Texte intégral
2017
Xu, Gang | Liu, Jian | Hu, Gang | Jonell, Tara N. | Chen, Lilei
To constrain organic matter compositions and origins, elemental (TOC, TN, C/N) and stable carbon (δ13C) and nitrogen isotope (δ15N) compositions are measured for surface sediments collected from muddy deposit along the Zhejiang coast, East China Sea. The results showed that the TOC, TN, C/N, δ13C, and δ15N were 0.19–0.67%, 0.03–0.09%, 6.76–9.22, −23.43 to −20.26‰, and 3.93–5.27‰, respectively. The δ13C values showed that the mixing inputs of terrigenous and marine organic matter generally dominated sedimentary organic matter in the west part, and the sedimentary organic matters were mainly influenced by the marine organic matter in the east part of the study area. A stable carbon isotope two end member mixing model estimates ~38% terrestrial -derived and ~62% marine-derived inputs to sedimentary organic matter. Microbial mineralization strongly controls δ15N values, and therefore cannot be used to identify the provenance of organic matter for the Zhenjiang coast.
Afficher plus [+] Moins [-]Aquaculture and urban marine structures facilitate native and non-indigenous species transfer through generation and accumulation of marine debris Texte intégral
2017
Campbell, Marnie L. | King, Staci | Heppenstall, Lara D. | van Gool, Ella | Martin, Ross | Hewitt, Chad L.
Both the invasion of non-indigenous marine species (NIMS) and the generation and accumulation of anthropogenic marine debris (AMD) are pervasive problems in coastal urban ecosystems. The biosecurity risks associated with AMD rafting NIMS have been described, but the role of aquaculture derived AMD has not yet been investigated as a biosecurity vector and pathway. This preliminary study targeted 27 beaches along the Coromandel Peninsula, New Zealand, collecting debris from belt transects. Plastic (specifically plastic rope) was the dominant AMD present on beaches. The most common biofouling taxa were hydroids, bryozoans, algae and polychaetes, with one NIMS pest species, Sabella spallanzanii, detected fouling plastic rope. Our findings demonstrate that aquaculture is an AMD (plastic rope) generating activity that creates biosecurity risk by enhancing the spread of NIMS. The rafting of S. spallanzanii on AMD generated at aquaculture facilities is currently an unmanaged pathway within New Zealand that needs attention.
Afficher plus [+] Moins [-]Geospatial risk assessment and trace element concentration in reef associated sediments, northern part of Gulf of Mannar biosphere reserve, Southeast Coast of India Texte intégral
2017
Krishnakumar, S. | Ramasamy, S. | Simon Peter, T. | Godson, Prince S. | Chandrasekar, N. | Magesh, N.S.
Fifty two surface sediments were collected from the northern part of the Gulf of Mannar biosphere reserve to assess the geospatial risk of sediments. We found that distribution of organic matter and CaCO3 distributions were locally controlled by the mangrove litters and fragmented coral debris. In addition, Fe and Mn concentrations in the marine sediments were probably supplied through the riverine input and natural processes. The Geo-accumulation of elements fall under the uncontaminated category except Pb. Lead show a wide range of contamination from uncontaminated-moderately contaminated to extremely contaminated category. The sediment toxicity level of the elements revealed that the majority of the sediments fall under moderately to highly polluted sediments (23.07–28.84%). The grades of potential ecological risk suggest that predominant sediments fall under low to moderate risk category (55.7–32.7%). The accumulation level of trace elements clearly suggests that the coral reef ecosystem is under low to moderate risk.
Afficher plus [+] Moins [-]Diversity of culturable yeasts associated with zoanthids from Brazilian reef and its relation with anthropogenic disturbance Texte intégral
2017
Paulino, Gustavo Vasconcelos Bastos | Félix, Ciro Ramon | Broetto, Leonardo | Landell, Melissa Fontes
Some of the main threats to coral reefs come from human actions on marine environment, such as tourism, overfishing and pollution from urban development. While several studies have demonstrated an association between bacteria and corals, demonstrating how these communities react to different anthropogenic stressors, yeast communities associated with corals have received far less attention from researchers. The aim of this work was therefore to describe cultivable yeasts associated with three coral species and to evaluate the influence of sewage discharge on yeasts community. We obtained 130 isolates, mostly belonging to phylum Ascomycota and many of them had previously been isolated from human samples or are considered pathogens. The mycobiota was more similar among corals collected from the same reef, indicating that the composition of reef yeast community is more influenced by environmental conditions than host species. We suggest further studies to elucidate which factors are most influential on the composition of the coral-associated yeast community.
Afficher plus [+] Moins [-]Composition, spatial distribution and sources of macro-marine litter on the Gulf of Alicante seafloor (Spanish Mediterranean) Texte intégral
2017
García-Rivera, Santiago | Sánchez Lizaso, José Luis | Millán, Jose María Bellido
Composition, spatial distribution and sources of macro-marine litter on the Gulf of Alicante seafloor (Spanish Mediterranean) Texte intégral
2017
García-Rivera, Santiago | Sánchez Lizaso, José Luis | Millán, Jose María Bellido
The composition, spatial distribution and source of marine litter in the Spanish Southeast Mediterranean were assessed. The data proceed from a marine litter retention programme implemented by commercial trawlers and were analysed by GIS. By weight, 75.9% was plastic, metal and glass. Glass and plastics were mainly found close to the coast. A high concentration of metal was observed in some isolated zones of both open and coastal waters. Fishing activity was the source of 29.16% of the macro-marine litter, almost 68.1% of the plastics, and 25.1% of the metal. The source of the other 60.84% could not be directly identified, revealing the high degree of uncertainty regarding its specific origin. Indirectly however, a qualitative analysis of marine traffic shows that the likely sources were merchant ships mainly in open waters and recreational and fishing vessels in coastal waters.
Afficher plus [+] Moins [-]Composition, spatial distribution and sources of macro-marine litter on the Gulf of Alicante seafloor (Spanish Mediterranean) Texte intégral
2017
García-Rivera, Santiago | Sánchez-Lizaso, José Luis | Bellido Millán, José María | Sánchez-Lizaso, José Luis | Universidad de Alicante. Departamento de Ciencias del Mar y Biología Aplicada | Biología Marina | Recursos Hídricos y Desarrollo Sostenible
The composition, spatial distribution and source of marine litter in the Spanish Southeast Mediterranean were assessed. The data proceed from a marine litter retention programme implemented by commercial trawlers and were analysed by GIS. By weight, 75.9% was plastic, metal and glass. Glass and plastics were mainly found close to the coast. A high concentration of metal was observed in some isolated zones of both open and coastal waters. Fishing activity was the source of 29.16% of the macro-marine litter, almost 68.1% of the plastics, and 25.1% of the metal. The source of the other 60.84% could not be directly identified, revealing the high degree of uncertainty regarding its specific origin. Indirectly however, a qualitative analysis of marine traffic shows that the likely sources were merchant ships mainly in open waters and recreational and fishing vessels in coastal waters. | We are grateful for the support of the PESCAL Project by European funds through General Secretary of Fisheries of Spain, led by CETMAR with the participation of the Joint Research Unit between the Spanish Oceanography Institute (IEO) and the University of Alicante (UA). Santiago García-Rivera was supported by PESCAL Project and a PhD grant from the University of Alicante.
Afficher plus [+] Moins [-]Trace element concentrations in the apex predator swordfish (Xiphias gladius) from a Mediterranean fishery and risk assessment for consumers Texte intégral
2017
Gobert, S. | Pasqualini, V. | Dijoux, J. | Lejeune, P. | Durieux, E.D.H. | Marengo, M.
Trace element concentrations in the apex predator swordfish (Xiphias gladius) from a Mediterranean fishery and risk assessment for consumers Texte intégral
2017
Gobert, S. | Pasqualini, V. | Dijoux, J. | Lejeune, P. | Durieux, E.D.H. | Marengo, M.
Swordfish (Xiphias gladius L., 1758) is an apex predator, highly migratory meso-pelagic fish widely distributed in the Atlantic Ocean and Mediterranean. As top predators, this fish may be the end reservoir of the bioaccumulation of trace elements in a food chain because they occupy higher trophic levels and are an important food source, causing them to be potentially hazardous to consume. This study aims to investigate the concentration of 18 trace elements of Swordfish, caught in the Mediterranean Sea and to discuss human exposure risks. The mean element levels in the fish muscles were clearly below the maximum allowable concentrations established by International food safety regulations. The data suggested that the risk is minor and acceptable for human health. The findings of this study amplify the scarce database on contaminants available, especially new data on “emerging elements”, for this species from the Mediterranean Sea.
Afficher plus [+] Moins [-]Trace element concentrations in the apex predator swordfish (Xiphias gladius) from a Mediterranean fishery and risk assessment for consumers Texte intégral
2017
Gobert, Sylvie | Pasqualini, Vanina | Dijoux, Jessica | Lejeune, Pierre | Durieux, Eric Dominique Henry | Marengo, Michel | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège | Stareso
peer reviewed | Swordfish (Xiphias gladius L., 1758) is an apex predator, highly migratory meso-pelagic fish widely distributed in the Atlantic Ocean and Mediterranean. As top predators, this fish may be the end reservoir of the bioaccumulation of trace elements in a food chain because they occupy higher trophic levels and are an important food source, causing them to be potentially hazardous to consume. This study aims to investigate the concentration of 18 trace elements of Swordfish, caught in the Mediterranean Sea and to discuss human exposure risks. The mean element levels in the fish muscles were clearly below the maximum allowable concentrations established by International food safety regulations. The data suggested that the risk is minor and acceptable for human health. The findings of this study amplify the scarce database on contaminants available, especially new data on “emerging elements”, for this species from the Mediterranean Sea. | Transpolmed Et Post Doc de Michel Marengo
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