P (phosphorus) and Fe (iron) are limiting elements and S (sulfur) is an important element of the biogeochemical cycle in the mangrove environment. To assess the effects of sulfur on the geochemical cycling of Fe and P at the sediment-plant interface, the speciation distributions of Fe, P and S in sediments were examined. The data showed that higher proportions of amorphous Fe, Fe-bound phosphate, chromium reducible sulfur and elemental sulfur were found in the rhizosphere, while more crystalline Fe, exchangeable phosphate and acid-volatile sulfide were determined in the non-rhizosphere. Sulfate application induced an increase in the Ex-P concentration, high P accumulation and high iron plaque deposition in the roots. In conclusion, sulfate applications had a significant influence on the geochemical cycling of Fe and P in the sediments. It significantly curtailed the Fe and P limit to plant growth and enhanced plant resistance to the rugged surroundings in mangrove.

Trace metal concentrations in muscle and liver tissues from two offshore species of skate were examined. Concentrations of mercury in muscle of Leucoraja circularis (n=20; 23–110.5cm total length, 157–490m water depth) and L. fullonica (n=24; 28.5–100cm total length, 130–426m water depth) were 0.02–1.8 and 0.04–0.61mgkg−1, respectively. Concentrations of both As and Hg increased with total length. Only the largest specimen had a concentration of Hg in muscle >1.0mgkg−1. Data were limited for specimens>90cm long, and further studies on contaminants in larger-bodied skates could usefully be undertaken.

Freshwater lenses associated to shell ridges and sand sheets exist on the coastal wetland of Samborombón Bay. As they constitute one of the most vulnerable aquifer systems, it is the aim of this study to determine the hydrogeochemical processes that condition the chemical quality of its groundwater and to assess their present and future capability as sustenance of native woods and local villagers. To achieve this, hydrogeomorphological field surveys were made and groundwater samples were taken. Results show that lenses have a mean thickness of 12m and its chemical quality depends on the dissolution of CO2(g) and carbonates, weathering of silicates and ion exchange. Lenses can be affected by long-term climatic variability and mining. The study of morphology and geochemistry of the freshwater lenses bring lights into important information about the management of water resources and conservation of the environment.

Major and trace metal concentrations were determined in western Adriatic sediment cores. Based on sediment chronology, the earliest anthropogenic influence appeared as a Zn and Pb increase in the Po River prodelta starting from ~1914. The increasing contamination signal of these trace metals propagated southward as far as 450km with a growing delay, taking ~10years to reach the south Adriatic Sea. Although greater inventories of excess trace metals in the northern sector pointed to the influence of the intense human activities in the Po River drainage basin and Venice lagoon system, we observed a reduction of excess trace metals from mid-1980s, related to the implementation of stricter environmental regulations on chemical wastewaters. In contrast, an increase in trace metal accumulation in surficial sediment from the 2000s in front of the cities of Ancona and Bari suggested a recent local input of trace metals, probably due to harbor activities.

The environmental quality differences between two groups of reefs in the Veracruz Reef System were evaluated. The North group of reefs is very close to Veracruz, an urban and port zone, whereas the South group is more isolated, with minor anthropogenic disturbances. To prove the hypothesis that the North group is more affected by anthropogenic activities, the concentrations of hydrocarbons in liver, metals and metalloids such as Se, As, Ba, Cd, Hg and V in muscle, and PAH metabolites in bile were evaluated, and related to biomarkers (transcript abundance of cytochrome P4501A, Vitellogenin, and Glutathione-S-transferase) in two species of fish: Haemulon aurolineatum and Ocyurus chysurus. H. aurolineatum presents the highest concentrations for many pollutants, but O. chysurus shows the most significant differences in pollutant concentrations and biomarkers between the two reef groups, suggesting that this species could be used as a sentinel in future studies in the Gulf of Mexico.

Nanoparticle emission from gasoline driven vehicles is reported to be significantly lower compared to diesel vehicles. Accordingly, there is no threshold limit implemented by the regulatory authorities in India for gasoline driven vehicles. Recent studies however indicate that this is true as far as the mass concentration of the nanoparticles is concerned. The number concentration of nanoparticles particularly of smaller dimensions is reported to be significantly higher for gasoline driven vehicles under certain operating range of speed and load. Smaller the dimension of the particles more are their residence time in environment and more susceptible are these particles to be inhaled by human respiratory and cardiovascular system. Thus an estimate of the size distribution of nano-sized particulate matter emission from gasoline driven vehicle is of immense importance in context to Indian urban population. In this direction, laboratory measurements are reported for the nanoparticle size distribution emitted from a gasoline engine under different loading conditions. On-field measurements are carried out in the wake of a stationary vehicle under idling and throttling condition. Simultaneous measurement of vehicular acceleration and deceleration is also reported along with nanoparticle distribution in the wake of a moving vehicle. The measurements reported in this paper reveal the need for deciding threshold value of number concentration to be implemented for gasoline vehicles by the Indian regulatory authorities.

Black bream (Acanthopagrus butcheri) were collected from an artificial inlet, Claisebrook Cove, Western Australia. Claisebrook Cove is adjacent to an historic contaminated site that was remediated during the 1990s. It was later identified as a priority area due to elevated levels of sediment contaminants including Zn, Cu, and Pb. Black bream were collected from this cove in 2005 and 2012 and their otoliths were analysed by laser ablation inductively coupled plasma mass spectrometry of the most recent growth zone. Levels of Zn and Mn, which are metabolically regulated, did not correlate with sediment contamination. However, reduction in sediment Cu levels over time coincided with reduced Cu otolith levels from 2005 to 2012. Results indicate that the elemental composition of the marginal edge of Black bream otoliths can identify bioavailable contaminants in an urban estuary and, with monitoring, can be utilized to establish long-term trends.

Stormwater runoff is the largest source of pollution in the Southern California Bight (SCB), resulting from untreated runoff and pollutants from urban watersheds entering the coastal waters after rainstorms. We make use of both satellite SAR and MODIS-Aqua ocean color imagery to examine two different components of runoff plumes, the surface slick and the sediment discharge. We expand on earlier satellite SAR studies by examining an extensive collection of multi-platform SAR imagery, spanning from 1992 to 2014, that provides a more comprehensive view of the plume surface slick characteristics, illustrated with distribution maps of the extent and flow direction of the plumes. The SAR-detected surface plumes are compared with coincident rain and runoff measurements, and with available measured shoreline fecal bacteria loads. We illustrate differences in the detection of SAR surface plumes with the sediment-related discharge plumes derived from MODIS imagery. A conceptual satellite stormwater runoff monitoring approach is presented.

Measurements of microplastics in biota and abiotic matrices are key elements of exposure and risk assessments for this emerging environmental pollutant. We investigated the abundance of microplastics in field-collected biota, sediment and water. An improved sediment extraction method, based on density separation was developed. For analysis of microplastics in biota we found that an adapted enzymatic digestion protocol using proteinase K performed best, with a 97% recovery of spiked plastic particles and no observed degradation effects on the plastics in subsequent Raman analysis. Field analysis revealed that 8 of 9 tested invertebrate species from the North Sea and 68% of analyzed individuals of brown trout (Salmo trutta) from the Swedish West Coast had microplastics in them. Based on the number of plastic particles per kg d.w. the microplastic concentrations found in mussels were approximately a thousand-fold higher compared to those in sediment and surface water samples from the same location.

China has been suffering serious particulate matter (PM) pollution in recent decades. Local emission and regional transport both contribute to PM pollution. Determining the contributions of local emissions vs. regional transport to PM concentrations is crucial in making effective PM control policies. This paper reviews the recent research on the contributions of regional transport to PM pollution in four regions in China, i.e., the northern China, eastern China, southern China, and the western China, respectively. The major findings include (1) HYSPLIT is the most popular methods in studies in all regions and often is used in combination with the CA, PSCF, and CWT techniques to investigate the transport pathways and source origins; (2) during the relatively polluted period, transport contributes over 50% of the PM concentrations in Beijing, Shanghai, Hangzhou, Guangzhou, Hong Kong, and Chengdu. Regional transport is important for PM pollution in major cities of China; and (3) regional transport exhibits clear seasonal variations and long term trends. The findings have important implication for emission control programs in these regions.