The potential impacts of underwater noise on marine mammals are widely recognised, but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. This paper characterises natural and anthropogenic contributors to underwater noise at two sites in the Moray Firth Special Area of Conservation, an important marine mammal habitat that may be exposed to increased shipping activity from proposed offshore energy developments. We aimed to establish a pre-development baseline, and to develop ship noise monitoring methods using Automatic Identification System (AIS) and time-lapse video to record trends in noise levels and shipping activity. Our results detail the noise levels currently experienced by a locally protected bottlenose dolphin population, explore the relationship between broadband sound exposure levels and the indicators proposed in response to the EU Marine Strategy Framework Directive, and provide a ship noise assessment toolkit which can be applied in other coastal marine environments.

The distributions of 41 polychlorinated biphenyls (PCBs) were determined in the aqueous phase, suspended particulate matter (SPM), and sediment of the Daliao River estuary in Liaodong Bay, Bohai Sea (China). The total PCB concentrations ranged from 5.51 to 40.28ngL−1 in the surface water, from 6.78 to 66.55ngL−1 dry weight in the SPM, and from 0.83 to 7.29ngg−1 dry weight in the sediment. The PCB concentrations in water, SPM, and sediment were moderate relative to those reported for other estuary and marine systems around the world. Sedimentary PCB concentrations decreased offshore due to the active deposition of laterally transported river-borne particles. The predominance of the highly chlorinated congeners for the water, SPM, and sediment samples are an indication of either a lack of degradation or the presence of nearby or recent releases into the environment.

A distance-based technique was used to assess the distribution and abundance of floating marine debris (>1cm) in the southeast Atlantic Ocean between Cape Town and Tristan da Cunha, crossing the southern edge of the South Atlantic ‘garbage patch’ predicted by surface drift models. Most litter was made of plastic (97%). Detection distances were influenced by the size and buoyancy of litter items. Litter density decreased from coastal waters off Cape Town (>100 itemskm−2) to oceanic waters (<10 itemskm−2), and was consistently higher (6.2±1.3 itemskm−2) from 3 to 8°E than in adjacent oceanic waters (2.7±0.3 itemskm−2) or in the central South Atlantic around Tristan (1.0±0.4 itemskm−2). The area with high litter density had few seaweeds, suggesting that most litter had been drifting for a long time. The results indicate that floating debris is accumulating in the South Atlantic gyre as far south as 34–35°S.

Due to their close proximity to the point sources of pollution, estuaries and harbours are exposed to metals. Mussels are used worldwide to monitor marine pollution due to their ability to take up contaminants and the ease of transplantation. Mussels were collected from two reference sites and transplanted in Richards Bay Harbour (2006 and 2010) and in three harbours. Transplanted and resident mussels were removed after 6weeks exposure and metal concentrations were analysed using ICP-MS techniques. Transplanted mussels had higher metal concentrations than the resident mussels. This was attributed to regulation of metals by the resident mussels. Metal regulation was greater in mussels that are continuously submerged as opposed to those that undergo tidal influences. For monitoring it is essential that the reference population for transplantation is considered carefully as upwelling events in the pristine reference location results in significant increases in metal bioaccumulation.

Volatile organic compound (VOC), nitrogen dioxide (NO2) and ozone (O3) concentrations were measured at one site in Rome urban air during 2011. The seasonal mean concentrations of VOCs varied from 78μg m−3 in winter to 37μg m−3 in summer. Total aromatic concentration was reduced by 59% during summertime, alkanes of 39% and alkenes of 71%. VOC diurnal pattern exhibited a primary peak during the morning and a secondary peak in the evening hours coinciding with rush–hour traffic. The high correlation between benzene and toluene evidenced their common origin probably due to vehicular traffic. In summer isoprene diurnal profile showed both biogenic and anthropogenic origin. NO2 and O3 daily trends during summertime evidenced both photostationary state typical conditions and photochemical smog episodes. VOC and O3 trends also evidenced a reduction in VOC levels during O3 formation. Based on the Maximum Incremental Reactivity scale, the highest contributors to ozone production in Rome were propene, ethene and toluene. Comparing data found in Rome at the same site in 1992, 2007 and 2011, a decreasing trend in VOC levels was observed, suggesting the effectiveness of European Directives on air quality. In addition, our results were confirmed by similar data found in other urban areas around the world.

Seasonal variation in trace metal contamination in surface sediments was studied through high resolution profiles assessed monthly by DGT probes in muddy sediments of the North Sea. General parameters such as pH, temperature, dissolved oxygen and sulfides were also recorded to estimate their role in the speciation of trace metals. Experimental data were included in a thermodynamic equilibrium model to calculate major (geo)chemical processes at the water–sediment interface and to predict the fate of the trace metals in case of (physico-)chemical changes. Results showed lowest Fe, Co, Ni and Cd concentrations in summer, which are most probably due to the very high sulfide concentrations according to our theoretical calculations. Cu and Pb behavior were found to be less influenced by sulfides, since they are also strongly associated to organic matter. The whole set of results clearly indicated that metal speciation in these sediments is controlled by sulfides and OM contents.

In this study, 75 samples of two 210Pb-dated cores from the southwest of the Caspian Sea were analysed for 30 compounds of polycyclic aromatic hydrocarbons (PAHs). The TPAH29 flux of the last six centuries ranged from 16.3 to 177.3 and 22.3 to 426.2ngcm−2y−1 in the Rezvanshahr and Anzali core sediments, respectively. Prior to 1840, four distinct maxima in PAH fluxes (61–426.2ngcm−2y−1) with a low weathered petrogenic pattern were found in each of the core sediments. Simultaneity of distinct peaks of PAH fluxes before 1840 and Caspian Sea level high-stands during the Little Ice Age (LIA), revealed the high importance of this phenomenon in washing and transport of land-based oil pollution into the Caspian Sea. An overall increase in some diagnostic ratios (Flu/202, IP/276 and BaA/228), especially after 1940, indicated increase of pyrogenic PAHs as a result of industrial development in the catchment area.

This paper tests the adequacy of using the lattice Boltzmann method in large-scale oil spill modelling, such as the Lebanon oil spill. Several numerical experiments were performed in order to select the most appropriate lattice and to decide between the single- and two-relaxation time models. Large-scale oil spills require simulations with short computational times. In order to speed up the computation and preserve adequate accuracy of the model, five different flux limiting interpolation techniques were compared and evaluated. The model was validated on the Lebanon oil spill with regard to the oil-slick position and concentrations in the sea, and the beaching area on the coast. Good agreement with satellite images of the slick and field data on beaching was achieved. The main advantages of the applied method are the capability of simulating very low oil concentrations and computational times that are by an order of magnitude shorter compared to similar models.

Drinking water shortage has become worse in recent decades. A new capacitive deionization (CDI) method for increasing water supplies through the effective desalination of seawater has been developed. Silver as nano Ag and Ag@C which was prepared by carbonization of the Ag+-β-cyclodextrin complex at 573K for 30min can add the antimicrobial function into the CDI process. The Ag@C and Ag nanoparticles dispersed on reduced graphene oxide (Ag@C/rGO and nano Ag/rGO) were used as the CDI electrodes. The nano Ag/rGO and Ag@C/rGO electrodes can reduce the charging resistant, and enhance the electrosorption capability. Better CDI efficiencies with the nano Ag/rGO and Ag@C/rGO electrodes can therefore be obtained. When reversed the voltage, the electrodes can be recovered up to 90% within 5min. This work presents the feasibility for the nano Ag and Ag@C on rGO electrodes applied in CDI process to produce drinking water from seawater or saline water.

This study compared species identity, microplastics, chemical and microbial contamination between consumption mussels and wild type mussels, collected at Belgian department stores and Belgian groynes and quaysides, respectively. Species identification based on genetic analysis showed a high number of Mytilus (M.) edulis compared to M. galloprovincialis and M. edulis/galloprovincialis hybrid mussels. The number of total microplastics varied from 2.6 to 5.1fibres/10g of mussel. A higher prevalence of orange fibres at quaysides is related to fisheries activities. Chemical contamination of polycyclic aromatic hydrocarbons and polychlorobiphenyls could be related to industrial activities and water turbidity, with maximum concentrations at the quayside of port Zeebrugge. The inverse was noted for Escherichia coli contamination, which was relatively low at Zeebrugge quayside with a total count of 3.9×102CFU/100g tissue, due to limited agricultural effluents. Results of this complementary analysis stress the importance of integrated monitoring and quality assessment.