In this study, basic sediment properties, nutrient flux, and nitrogen cycle (including denitrification, anaerobic ammonium oxidation [anammox], nitrification, and dissimilatory nitrate reduction to ammonium [DNRA]) were investigated at two sampling sites with different tree ages in the mangrove region of the Jiulong River Estuary, China. The results show that sediments at mangrove flat area have relatively strong capability to reduce NO3−, in which the DNRA rate is relatively high (204.53±48.32μmolNm−2h−1), which is approximately 75.7–85.9% of the total NO3− reduction, while the denitrification and anammox rates are relatively low – only approximately 5.6–9.5% and 8.5–14.8% of the total NO3− reduction, respectively. Thus, in the nitrogen-enriched subtropical mangrove system, DNRA is the main pathway to reduce NO3−, and most of the input nitrogen is conserved as NH4+ in the system, which assures high productivity of the mangrove system.

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.

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.

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.

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.

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.

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.

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.

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.

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.