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Ingestion of marine litter by loggerhead sea turtles, Caretta caretta, in Portuguese continental waters Full text
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.
Show more [+] Less [-]Enrichment and identification of naphthalene-degrading bacteria from the Persian Gulf Full text
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.
Show more [+] Less [-]Characteristics of individual particles in a severe short-period haze episode induced by biomass burning in Beijing Full text
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.
Show more [+] Less [-]Long-term aging and degradation of microplastic particles: Comparing in situ oceanic and experimental weathering patterns Full text
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.
Show more [+] Less [-]Occurrence, spatial deposition and footprint of polybrominated diphenyl ethers in surficial sediments of Bushehr peninsula, the Persian Gulf Full text
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.
Show more [+] Less [-]Distribution and contamination of heavy metals in surface sediments of the Daya Bay and adjacent shelf, China Full text
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.
Show more [+] Less [-]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 Full text
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.
Show more [+] Less [-]Public awareness and attitudes towards marine protection in the United Kingdom Full text
2016
Hawkins, Julie P. | O'Leary, Bethan C. | Bassett, Nicola | Peters, Howard | Rakowski, Sarah | Reeve, Georgina | Roberts, Callum M.
Public perception research evaluating awareness and attitudes towards marine protection is limited in the United Kingdom (UK) and worldwide. Given public opinion can help drive policy and affect its successful delivery we conducted nationwide surveys in 2005, 2010 and 2015 to assess public knowledge of UK (England, Scotland and Wales) sea ‘health’ and management. Respondents from all three surveys were relatively pessimistic about sea ‘health’, perceiving this as poor-fair and largely in decline. Enthusiasm for marine conservation was high with almost two-thirds of respondents in each survey wanting >40% of UK seas highly protected from fishing and damaging activities. In 2015 there was considerable dissatisfaction with the rate of progress in Marine Conservation Zone designation and over three-quarters of respondents considered dredging and trawling to be inappropriate in protected areas, contrary to management. The UK government and devolved administrations need to better align future conservation and management with public expectations.
Show more [+] Less [-]Microbiome analysis and detection of pathogenic bacteria of Penaeus monodon from Jakarta Bay and Bali Full text
2016
Oetama, Vincensius S.P. | Hennersdorf, Philipp | Abdul-Aziz, Muslihudeen A. | Mrotzek, Grit | Haryanti, Haryanti | Saluz, Hans Peter
Penaeus monodon, the Asian black tiger shrimp is one of the most widely consumed marine crustaceans worldwide. In this study, we examine and compare the fecal microbiota of P. monodon from highly polluted waters around Jakarta Bay, with those of less polluted waters of Bali. Using next generation sequencing techniques, we identified potential bacterial pathogens and common viral diseases of shrimp. Proteobacteria (96.08%) was found to be the most predominant phylum, followed by Bacteriodetes (2.32%), Fusobacteria (0.96%), and Firmicutes (0.53%). On the order level, Vibrionales (66.20%) and Pseudoaltermonadales (24.81%) were detected as predominant taxa. qPCR profiling was used as a confirmatory step and further revealed Vibrio alginolyticus and Photobacterium damselae as two potential pathogenic species present in most of the samples. In addition, viral diseases for shrimp were discovered among the samples, WSSV in Jakarta free-living samples, YHV in Bali free-living samples and IHHNV in both.
Show more [+] Less [-]Prickly business: abundance of sea urchins on breakwaters and coral reefs in Dubai Full text
2016
Bauman, Andrew G. | Dunshea, Glenn | Feary, David A. | Hoey, Andrew S.
Echinometra mathaei is a common echinoid on tropical reefs and where abundant plays an important role in the control of algal communities. Despite high prevalence of E. mathaei on southern Persian/Arabian Gulf reefs, their abundance and distribution is poorly known. Spatial and temporal patterns in population abundance were examined at 12 sites between breakwater and natural reef habitats in Dubai (UAE) every 3months from 2008 to 2010. Within the breakwater habitat, densities were greatest at shallow wave-exposed sites, and reduced with both decreasing wave-exposure and increasing depth. Interestingly, E. mathaei were significantly more abundant on exposed breakwaters than natural reef sites, presumably due to differences in habitat structure and benthic cover. Population abundances differed seasonally, with peak abundances during summer (July–September) and lower abundances in winter (December–February). Seasonal fluctuations are likely the result of peak annual recruitment pulses coupled with increased fish predation from summer to winter.
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