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Baseline of polycyclic aromatic hydrocarbons in the surface sediment and sea cucumbers (Holothuria leucospilota and Stichopus hermanni) in the northern parts of Persian Gulf Texte intégral
2016
Polycyclic aromatic hydrocarbons (PAHs) were determined in the surface sediments and in the sea cucumbers (Holothuria leucospilota and Stichopus hermanni) from around six Islands in the northern parts of Persian Gulf. The ranges of the average concentrations of PAHs in surface sediments, H. leucospilota and S. hermanni were 10.33–186.16ngg−1 dw, 12.49–505.44ngg−1 dw and 8.08–389.39ngg−1 dw, respectively. The spatial distribution of PAHs reveals that pollutant concentration is relatively higher at the western parts of Persian Gulf. International sedimentary quality guidelines (TEL-PEL) indicated a low probability of harmful effects to benthic organisms. PAH source identification showed that the PAHs in the sediments come from pyrogenic and mixed origin.
Afficher plus [+] Moins [-]Geochemical partitioning and pollution assessment of Ni and V as indicator of oil pollution in surface sediments from Shadegan wildlife refuge, Iran Texte intégral
2016
Chaharlang, Behnam Heidari | Bakhtiari, Alireza Riyahi | Mohammadi, Jahangard | Farshchi, Parvin
The total concentrations and chemical partitioning of Ni, V and Fe have been assessed in surface sediments from 160 sites along the Shadegan wildlife refuge. The results showed that the average total level of Ni, V and Fe in surface sediments were 45.08±12.09, 25.25±20.8 and 25,979.01±6917.91μg/g dw, respectively. On the average, the chemical speciation of Ni, V and Fe in most stations were in the order of residual>oxidisable-organic>acid-reducible>exchangeable. In all fractions, the residual was accounted the highest proportion for the metals analyzed. Among the non-residual phases, the proportion of heavy metals in organic matter fraction was higher than other phases collected from all locations. The comparison between measured values in this study and some fresh water sediment quality guidelines indicated that the levels of nickel would be expected to sporadically cause harmful biological impacts on biota in the Shadegan wildlife refuge.
Afficher plus [+] Moins [-]Polychlorinated biphenyls and organochlorine pesticides in surface sediments from Shantou Bay, China: Sources, seasonal variations and inventories Texte intégral
2016
Shi, Jingchun | Li, Ping | Li, Yuelin | Liu, Wenhua | Zheng, Gene Jin-Shu | Xiang, Li | Huang, Zhongwen
Sediments from Shantou Bay, China, were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) for the first time. The concentrations of PCBs and OCPs were 0.54–55.5ngg−1 and 2.19–16.9ngg−1 (dry weight), respectively. Source identification showed that tri-CBs and penta-CBs were manufactured and used in the last century, while usage of antifouling paint might still serve as a significant source of sediment DDT. Concentrations of PCBs and HCHs significantly (p<0.05) increased after wet season, suggesting that atmospheric deposition and surface runoff played an important role in distribution of historical pollutants. Additionally, the adverse biological effects could occasionally occur for DDT in sediments. The mass inventories were preliminarily calculated for PCBs (90.1ngcm−2 and 0.09tons) and OCPs (61.8ngcm−2 and 0.062tons) in Shantou Bay, while as part of the “reservoir” of organochlorine compounds to the global ocean, its role cannot be neglected.
Afficher plus [+] Moins [-]Coral reef fish assemblages along a disturbance gradient in the northern Persian Gulf: A seasonal perspective Texte intégral
2016
Ghazilou, Amir | Shokri, Mohammad Reza | Gladstone, William
Seasonal dynamics of coral reef fish assemblages were assessed along a gradient of potential anthropogenic disturbance in the Northern Persian Gulf. Overall, the attributes of coral reef fish assemblages showed seasonality at two different levels: seasonal changes irrespective of the magnitude of disturbance level (e.g. species richness), and seasonal changes in response to disturbance level (e.g. total abundance and assemblage composition). The examined parameters mostly belonged to the second group, but the interpretation of the relationship between patterns of seasonal changes and the disturbance level was not straightforward. The abundance of carnivorous fishes did not vary among seasons. SIMPER identified the family Nemipteridae as the major contributor to the observed spatiotemporal variations in the composition of coral reef fish assemblages in the study area.
Afficher plus [+] Moins [-]Purification and characterization of biosurfactant produced by Bacillus licheniformis Y-1 and its application in remediation of petroleum contaminated soil Texte intégral
2016
Liu, Boqun | Liu, Jinpeng | Ju, Meiting | Li, Xiaojing | Yu, Qilin
In our previous research, a petroleum degrading bacteria strain Bacillus licheniformis Y-1 was obtained in Dagang Oilfield which had the capability of producing biosurfactant. This biosurfactant was isolated and purified in this work. The biosurfactant produced by strain Y-1 had the capability to decrease the surface tension of water from 74.66 to 27.26mN/m, with the critical micelle concentration (CMC) of 40mg/L. The biosurfactant performed not only excellent stabilities against pH, temperature and salinity, but also great emulsifying activities to different kinds of oil, especially the crude oil. According to the results of FT-IR spectrum and 1H NMR spectrum detection, the surfactant was determined to be a cyclic lipopeptide. Furthermore, through the addition of surfactant, the effect of petroleum contaminated soil remediation by fungi got a significant improvement.
Afficher plus [+] Moins [-]White-faced storm-petrels Pelagodroma marina predated by gulls as biological monitors of plastic pollution in the pelagic subtropical Northeast Atlantic Texte intégral
2016
Furtado, Ricardo | Menezes, Dilia | Santos, Carolina Jardim | Catry, Paulo
Marine plastic pollution is rapidly growing and is a source of major concern. Seabirds often ingest plastic debris and are increasingly used as biological monitors of plastic pollution. However, virtually no studies have assessed plastics in seabirds in the deep subtropical North Atlantic. We investigated whether remains of white-faced storm-petrels (WFSP) present in gull pellets could be used for biomonitoring. We analysed 263 pellets and 79.0% of these contained plastic debris originating in the digestive tract of WFSP. Pellets with no bird prey did not contain plastics. Most debris were fragments (83.6%) with fewer plastic pellets (8.2%). Light-coloured plastics predominated (71.0%) and the most frequent polymer was HDPE (73.0%). Stable isotopes in toe-nails of WFSP containing many versus no plastics did not differ, indicating no individual specialisation leading to differential plastic ingestion. We suggest WFSP in pellets are highly suitable to monitor the little known pelagic subtropical Northeast Atlantic.
Afficher plus [+] Moins [-]Direct evidences on bacterial growth pattern regulating pyrene degradation pathway and genotypic dioxygenase expression Texte intégral
2016
Chen, Baowei | Huang, Jinyin | Yuan, Ke | Lin, Li | Wang, Xiaowei | Yang, Lihua | Luan, Tiangang
Pyrene degradation by Mycobacterium sp. strain A1-PYR was investigated in the presence of nutrient broth, phenanthrene and fluoranthene, respectively. Fast bacterial growth in the nutrient broth considerably enhanced pyrene degradation rate, whereas degradation efficiency per cell was substantially decreased. The addition of nutrient broth could not alter the transcription levels of all dioxygenase genotypes. In the PAH-only substrates, bacterial growth completely relied on biological conversion of PAHs into the effective carbon sources, which led to a higher degradation efficiency of pyrene per cell than the case of nutrient broth. Significant correlations were only observed between nidA-related dioxygenase expression and pyrene degradation or bacterial growth. The highest pyrene degradation rate in the presence of phenanthrene was consistent with the highest transcription level of nidA and 4,5-pyrenediol as the sole initial metabolite. This study reveals that bacterial growth requirement can invigorate degradation of PAHs by regulating metabolic pathway and genotypic enzyme expression.
Afficher plus [+] Moins [-]Dynamic fugacity model for accidental oil release during Arctic shipping Texte intégral
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.
Afficher plus [+] Moins [-]Levels of chemicals in two fish species from four Italian fishing areas Texte intégral
2016
Guerranti, Cristiana | Grazioli, Eleonora | Focardi, S. (Silvano) | Renzi, Monia | Perra, Guido
This paper reports the results of an assessment of contamination by polychlorinated biphenyls and polycyclic aromatic hydrocarbons in two demersal species of commercial importance. The organisms considered were Mullus barbatus and Engraulis encrasicolus from three marine areas off the Italian coasts: North and South Adriatic Sea and North Tyrrhenian Sea. The instrumental analyzes have revealed, in many samples examined, the presence of most of PCB congeners and 5 of the 16 PAHs considered. Organisms caught in the waters of Apulia have greater contamination values, while the samples from Tuscany showed the lowest ones, results probably referable to the environmental quality differences between the areas of origin, at least for PAHs, since the sampling areas are represented respectively by areas with presence of oil extraction plant (Adriatic), and by an area subject to environmental protection.
Afficher plus [+] Moins [-]Is existing legislation fit-for-purpose to achieve Good Environmental Status in European seas? Texte intégral
2016
Boyes, Suzanne J. | Elliott, Michael | Murillas-Maza, Arantza | Papadopoulou, Nadia | Uyarra, Maria C.
Recent additions to marine environmental legislation are usually designed to fill gaps in protection and management, build on existing practices or correct deficiencies in previous instruments. Article 13 of the European Marine Strategy Framework Directive (MSFD) requires Member States to develop a Programme of Measures (PoM) by 2015, to meet the objective of Good Environmental Status (GES) for their waters by 2020. This review explores key maritime-related policies with the aim to identify the opportunities and threats that they pose for the achievement of GES. It specifically examines how Member States have relied on and will integrate existing legislation and policies to implement their PoM and the potential opportunities and difficulties associated with this. Using case studies of three Member States, other external impediments to achieving GES are discussed including uses and users of the marine environment who are not governed by the MSFD, and gives recommendations for overcoming barriers.
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