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Ecological assessment of a heavily human-stressed area in the Gulf of Milazzo, Central Mediterranean Sea: an integrated study of biological, physical and chemical indicators Texte intégral
2016
D'Alessandro, Michela | Esposito, Valentina | Giacobbe, Salvatore | Renzi, Monia | Mangano, Maria Cristina | Vivona, Pietro | Consoli, Pierpaolo | Scotti, Gianfranco | Andaloro, Franco | Romeo, Teresa
Marine environmental disturbance can be assessed directly from physical and chemical parameters, or indirectly by the study of indicator species. In this study, an integrated approach to monitor the Gulf of Milazzo, labeled as a highly contaminated site, is presented. A total of 83 samples were collected from hard and soft bottoms in 2010. In sum, 2739 specimens belonging to 246 taxa, two first records for the Tyrrhenian Sea (Micronephthys stammeri and Nicomache lumbricalis) and three nonindigenous species (Brachidontes pharaonis, Crassostrea gigas and Notomastus aberans) were recorded. Biodiversity and biotic indices and their relationship with sediment parameters and the level of pollutants were assessed to describe faunal assemblage and evaluate environmental quality. Pearson tests evidenced significant negative correlation between polychlorinated biphenyls (PCBs) and specific richness (p<0.10). A comparison of the standard and recorded biotic values showed that M-AMBI seems to be the index more representative of ecological quality status (EcoQ) in the Gulf of Milazzo. No evident signs were highlighted on the complex.
Afficher plus [+] Moins [-]Ingestion of marine litter by loggerhead sea turtles, Caretta caretta, in Portuguese continental waters Texte intégral
2016
Nicolau, Lídia | Marçalo, Ana | Ferreira, Marisa | Sá, Sara | Vingada, José | Eira, Catarina
The accumulation of litter in marine and coastal environments is a major threat to marine life. Data on marine litter in the gastrointestinal tract of stranded loggerhead turtles, Caretta caretta, found along the Portuguese continental coast was presented. Out of the 95 analysed loggerheads, litter was present in 56 individuals (59.0%) and most had less than 10 litter items (76.8%) and less than 5g (dm) (96.8%). Plastic was the main litter category (frequency of occurrence=56.8%), while sheet (45.3%) was the most relevant plastic sub-category. There was no influence of loggerhead stranding season, cause of stranding or size on the amount of litter ingested (mean number and dry mass of litter items per turtle). The high ingested litter occurrence frequency in this study supports the use of the loggerhead turtle as a suitable tool to monitor marine litter trends, as required by the European Marine Strategy Framework Directive.
Afficher plus [+] Moins [-]Bioindicators as metrics for environmental monitoring of desalination plant discharges Texte intégral
2016
de-la-Ossa-Carretero, J.A. | Del-Pilar-Ruso, Y. | Loya-Fernández, A. | Ferrero-Vicente, L.M. | Marco-Méndez, C. | Martinez-Garcia, E. | Giménez-Casalduero, F. | Sánchez-Lizaso, J.L.
Bioindicators as metrics for environmental monitoring of desalination plant discharges Texte intégral
2016
de-la-Ossa-Carretero, J.A. | Del-Pilar-Ruso, Y. | Loya-Fernández, A. | Ferrero-Vicente, L.M. | Marco-Méndez, C. | Martinez-Garcia, E. | Giménez-Casalduero, F. | Sánchez-Lizaso, J.L.
Development of desalination projects requires simple methodologies and tools for cost-effective and environmentally-sensitive management. Sentinel taxa and biotic indices are easily interpreted in the perspective of environment management. Echinoderms are potential sentinel taxon to gauge the impact produced by brine discharge and the BOPA index is considered an effective tool for monitoring different types of impact. Salinity increase due to desalination brine discharge was evaluated in terms of these two indicators. They reflected the environmental impact and recovery after implementation of a mitigation measure. Echinoderms disappeared at the station closest to the discharge during the years with highest salinity and then recovered their abundance after installation of a diffuser reduced the salinity increase. In the same period, BOPA responded due to the decrease in sensitive amphipods and the increase in tolerant polychaete families when salinities rose. Although salinity changes explained most of the observed variability in both indicators, other abiotic parameters were also significant in explaining this variability.
Afficher plus [+] Moins [-]Bioindicators as metrics for environmental monitoring of desalination plant discharges Texte intégral
2016
de-la-Ossa-Carretero, Jose Antonio | Del-Pilar-Ruso, Yoana | Loya-Fernández, Angel | Ferrero-Vicente, Luis Miguel | Marco-Méndez, Candela | Martinez-Garcia, Elena | Gimenez-Casalduero, Francisca | Sánchez-Lizaso, José Luis | Universidad de Alicante. Departamento de Ciencias del Mar y Biología Aplicada | Biología Marina | Recursos Hídricos y Desarrollo Sostenible
Development of desalination projects requires simple methodologies and tools for cost-effective and environmentally-sensitive management. Sentinel taxa and biotic indices are easily interpreted in the perspective of environment management. Echinoderms are potential sentinel taxon to gauge the impact produced by brine discharge and the BOPA index is considered an effective tool for monitoring different types of impact. Salinity increase due to desalination brine discharge was evaluated in terms of these two indicators. They reflected the environmental impact and recovery after implementation of a mitigation measure. Echinoderms disappeared at the station closest to the discharge during the years with highest salinity and then recovered their abundance after installation of a diffuser reduced the salinity increase. In the same period, BOPA responded due to the decrease in sensitive amphipods and the increase in tolerant polychaete families when salinities rose. Although salinity changes explained most of the observed variability in both indicators, other abiotic parameters were also significant in explaining this variability. | These surveys were funded by the Mancomunidad de Canales del Taibilla.
Afficher plus [+] Moins [-]Enrichment and identification of naphthalene-degrading bacteria from the Persian Gulf Texte intégral
2016
Hassanshahian, Mehdi | Boroujeni, Negar Amini
Naphthalene is a ubiquitous pollutant of the marine environment, and naphthalene biodegradation has been receiving constant scientific consideration. For cleanup of aromatic contaminated sites, bioremediation methods are considered as economical and safe approaches for the marine environment. The aims of this research are isolation and characterization of naphthalene-degrading bacteria from some marine samples of the Persian Gulf. Fifty four naphthalene-degrading bacteria were isolated from marine samples (sediment and seawater) that are enriched in ONR7a medium with naphthalene as the only carbon source. Some screening tests such as growth at high concentration of naphthalene, bioemulsifier production and surface hydrophobicity were done to select the best and prevalent strains for naphthalene degradation. Determination of the nucleotide sequence of the gene encoding for 16S rRNA shows that these isolated strains belong to these genera: Shewanella, Salegentibacter, Halomonas, Marinobacter, Oceanicola, Idiomarina and Thalassospira. These strains can degrade half of the percentage of naphthalene in 10days of incubation. This research is the first report on isolation of these genera from the Persian Gulf as naphthalene-degrader.
Afficher plus [+] Moins [-]Characteristics of individual particles in a severe short-period haze episode induced by biomass burning in Beijing Texte intégral
2016
Niu, Hongya | Cheng, Wenjing | Hu, Wei | Pian, Wei
Atmospheric particles were investigated from a haze episode in autumn 2012 in Beijing that was caused by transported pollutants emitted from biomass burning during the crop harvest season in the North China Plain. Four samples from haze and one sample from clean atmosphere were collected in sequence by a multiple-stage cascade impactor. Based on morphology and elemental compositions, the particles were classified into five types: accumulation-mode secondary particles with and without coating, naked and core–shell soot, and other particles. The ratios of accumulation-mode secondary particles to soot containing particles were 4.0, 2.3, 1.7, 1.8, and 5.5, i.e., secondary particles in haze were proportionally less abundant than those in clean air, which was caused by the different dominant secondary formation mechanisms during hazy and clean periods. Meanwhile, the ratios of particles with coating to those without coating were 0.5, 1.0, 0.7, 0.6, and 0.2, implying that the particles in haze were likely more hygroscopic than those in clean air. In haze, the size distributions of particles were multi-modal, with main modes of approximately 0.55–0.85 μm, suggesting that the particles were from multiple sources due to the transported biomass burning plumes mixed with urban air. The size distribution was unimodal in clean air, and the mode was approximately 0.35 μm, with a mean equivalent diameter of 0.45 μm. The core–shell ratio distribution for soot particles collected in haze induced by biomass-burning aerosols was quite different from those in clean air, and soot particles were more aged in haze samples.
Afficher plus [+] Moins [-]Long-term aging and degradation of microplastic particles: Comparing in situ oceanic and experimental weathering patterns Texte intégral
2016
Brandon, Jennifer | Goldstein, Miriam | Ohman, Mark D.
Polypropylene, low-density polyethylene, and high-density polyethylene pre-production plastic pellets were weathered for three years in three experimental treatments: dry/sunlight, seawater/sunlight, and seawater/darkness. Changes in chemical bond structures (hydroxyl, carbonyl groups and carbon-oxygen) with weathering were measured via Fourier Transform Infrared (FTIR) spectroscopy. These indices from experimentally weathered particles were compared to microplastic particles collected from oceanic surface waters in the California Current, the North Pacific Subtropical Gyre, and the transition region between the two, in order to estimate the exposure time of the oceanic plastics. Although chemical bonds exhibited some nonlinear changes with environmental exposure, they can potentially approximate the weathering time of some plastics, especially high-density polyethylene. The majority of the North Pacific Subtropical Gyre polyethylene particles we measured have inferred exposure times>18months, with some >30months. Inferred particle weathering times are consistent with ocean circulation models suggesting a long residence time in the open ocean.
Afficher plus [+] Moins [-]Occurrence, spatial deposition and footprint of polybrominated diphenyl ethers in surficial sediments of Bushehr peninsula, the Persian Gulf Texte intégral
2016
Aghadadashi, Vahid | Mehdinia, Ali
The concentrations of polybrominated diphenyl ethers (PBDEs) were determined in the surficial sediments of Bushehr coasts, the Persian Gulf. Eighteen samples were collected from 6 sites at distances of 500, 1000 and 1500m from the coast. PBDEs were detected in all the samples, indicating their widespread occurrence in marine sediments of the studied area. BDE-209 and ∑7PBDEs were in the range of n.d. (not detected) to 6.29ngg−1 and n.d. to 0.62ngg−1 dw, respectively. The studied area can be classified as the region with the minimal contamination values reported globally as yet. The concentrations of PBDEs were lower than the Canadian benchmarks, and risk quotient assessments demonstrated low ecological risk. BDE-183 and then BDE-153 were the congeners with the highest detection frequencies in the stations, confirming extensive occurrence of Octa-mix in the studied area.
Afficher plus [+] Moins [-]Distribution and contamination of heavy metals in surface sediments of the Daya Bay and adjacent shelf, China Texte intégral
2016
Zhao, Guangming | Ye, Siyuan | Yuan, Hongming | Ding, Xigui | Wang, Jin
Heavy metal (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn)) concentrations from the Daya Bay and adjacent shelf were determined to evaluate their levels and spatial distributions. The measured concentrations ranged from 1.94–13.67mg/kg for As, 0.03–0.13mg/kg for Cd, 10–85mg/kg for Cr, 1–39.5mg/kg for Cu, 0.01–0.09mg/kg for Hg, 11–56mg/kg for Pb, and 13–125mg/kg for Zn. The spatial distributions exhibited a gradual decrease from west to east, and the concentrations of the seven heavy metals met the China Marine Sediment Quality criteria. Both metal enrichment factor (EF) and geo-accumulation index (Igeo) values showed that Cd, Cr, Cu, Hg, and Zn were not at pollution levels in the region. Multivariate analysis (PCA) revealed that lithogenic factors dominated the distribution of most of the metals, whereas As and Hg were clearly influenced by anthropogenic input.
Afficher plus [+] Moins [-]Spatial and temporal analysis of the risks posed by polychlorinated biphenyl and metal contaminants in dab (Limanda limanda) collected from waters around England and Wales Texte intégral
2016
Nicolaus, E.E Manuel | Wright, Serena R. | Bolam, Thi P.C. | Barber, Jonathan L. | Bignell, John P. | Lyons, Brett P.
The metals cadmium, mercury and lead, and the ICES7 CB levels were analysed in the common dab Limanda limanda to investigate whether concentrations of these determinants are at levels above established OSPAR assessment criteria around England and Wales. The results indicate that CB118 is above the OSPAR derived EAC at 22 out of 29 sampled stations, with 15 showing significant reductions. Cadmium is increasing significantly at six stations with two sites in the North Sea breaching corresponding OSPAR EAC. Mean results for all other PCBs and metals stayed below the EAC thresholds, with Hg concentrations even falling below BAC levels at South Eddystone located in the western English Channel. This study shows that PCBs banned over 20years ago are still found at concentrations in fish liver tissues which may pose a health risk to both the individual fish and their predators.
Afficher plus [+] Moins [-]Determination of PM2.5 and polycyclic aromatic hydrocarbons from incense burning emission at shrine for health risk assessment Texte intégral
2016
Bootdee, Susira | Chantara, Somporn | Prapamontol, Tippawan
This study aims to determine fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) bounded with PM2.5 emitted from incense burning at shrine to assess human health risk. The PM2.5 samples were collected by a mini volume air sampler during special occasions and normal period at a shrine located in the city center of Chiang Mai, Thailand. The samples were analyzed for 16-PAHs by GC–MS. The descending order of 8- and 24-hrs PM2.5 concentrations (μg/m3) were 625 ± 147 and 406 ± 159 (Chinese New Year) > 184 ± 85 and 133 ± 71 (other special occasions) > 100 ± 35 and 50 ± 20 (normal period). Their concentrations in each occasion were significantly different due to number of visitors and amount of incense being burned. Total PAHs concentrations (ng/m3) for 8- and 24-hrs in descending order were 90 ± 41 and 45 ± 29 (Chinese New Year), 71 ± 30 and 30 ± 12 (other special occasions) and 25 ± 15 and 14 ± 9 (normal periods). Correlation between PM2.5 and total PAHs concentrations was relatively strong. In addition, PM2.5 concentrations were highly correlated (r = 0.618) with carcinogenic PAHs (c-PAHs) indicated that carcinogenic compounds were dominant in particulate PAHs and generated from incense burning. The values of toxicity equivalent concentration (TEQ) indicate human health risk from PAHs inhalation. According to European guideline, it should be less than1 ng/m3 in ambient air. During Chinese New Year, they were relatively high (32 ± 27 ng/m3 (8 h) and 10 ± 4 ng/m3 (24 h)). Moreover, the isometric ratio analysis revealed that emission from incense burning was the main source of PM2.5 and PM2.5-bound PAHs.
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