Sediment cores and overlying water samples were collected at four sites in Tianjin Coastal Zone, Bohai Bay, to investigate nutrient (N, P and Si) exchanges across the sediment-water interface. The exchange fluxes of each nutrient species were estimated based on the porewater profiles and laboratory incubation experiments. The results showed significant differences between the two methods, which implied that molecular diffusion alone was not the dominant process controlling nutrient exchanges at these sites. The impacts of redox conditions and bioturbation on the nutrient fluxes were confirmed by the laboratory incubation experiments. The results from this study showed that the nutrient fluxes measured directly from the incubation experiment were more reliable than that predicted from the porewater profiles. The possible impacts causing variations in the nutrient fluxes include sewage discharge and land reclamation.

The occurrence of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyl (PCBs) in urban atmosphere in Guangzhou, China were assessed using homing pigeons as a biomonitor. Contaminant concentrations in lung were significantly higher than those in liver and fat, indicating chemical uptake was mainly through respiratory route. Tricyclic PAHs and low chlorinated PCBs dominated composition of PAHs and PCBs in homing pigeons, similar as their composition in local atmosphere. Different age-dependent bioaccumulation patterns were noted for PAHs and PCBs. For 1-year old homing pigeons, higher levels of PAHs and PCBs in lung and liver tissues were probably ascribed to more intense flying than 5- and 10-year groups. Fat concentrations of PCBs were greater in aged pigeons than 1-year old pigeons, but PAH concentrations in fat slightly decreased in aged pigeons because of relatively fast biotransformation. Overall, homing pigeons could serve as a suitable biomonitor for urban atmospheric contaminants in coastal cities.Homing pigeons could serve as a good biomonitor for PAHs and PCBs in urban atmosphere, yet different biotransformation potential of the chemicals caused different bioaccumulation patterns in pigeon fat.

Coastal ecosystems are receiving elevated loads of nitrogen (N) from anthropogenic sources. Understanding how excessive N loading affects bacterioplankton communities is critical to predict the biodiversity of marine ecosystems under conditions of eutrophic disturbance. In this study, oligotrophic coastal water microcosms were perturbed with nitrate in two loading modes: 1) one-off loading at the beginning of the incubation period; and 2) periodic loading every two days for 16days. Turnover in the bacterioplankton community was investigated by 16S rDNA gene amplicon sequencing. The alpha diversity of the bacterioplankton community showed great temporal variability and similar responses to the different treatments. Bacterioplankton community composition was influenced remarkably by time and N loading mode. The effects of N loading on bacterioplankton community structure showed obvious temporal variation, probably because of the great temporal variation in environmental parameters. This study provides insights into the effects of N pollution in anthropogenically perturbed marine environments.

This study assessed the concentration and composition of Polycyclic Aromatic Hydrocarbons (PAHs) in plastic pellets, collected from sandy beaches and considered different resin and colour tones. Results showed that polyethylene pellets, while displaying a greater range of total PAH concentrations did not differ significantly from polypropylene pellets. More importantly, both resin types demonstrated predictable increases in total PAH across a spectrum of darkening colour tones. Multivariate comparisons of 36 PAH groups, further showed considerable variability across resin type and colour, with lighter coloured pellets comprising lower molecular weight, while darker pellets contained higher weight PAHs. Overall, we show predictable variation in PAH concentrations and compositions of plastic pellets of different ages and resin types that will directly influence the potential for toxicological effects. Our findings suggest that monitoring programs should take these attributes into account when assessing the environmental risks of microplastic contamination of marine and coastal habitats.

Corexit, an EPA-approved chemical dispersant, was intensively used during the 2010 Deepwater Horizon Oil Spill in the Gulf of Mexico. Current studies surrounding Corexit have mainly focused on its toxicity and oil removal capacity. The potential impact of Corexit on the surface ocean carbon dynamics has remained largely unknown. The spontaneous assembly of DOM (dissolved organic matter) polymers into microgels (POM, particulate organic matter) was demonstrated previously that it can influence various critical processes, such as colloidal pump, microbial loops, and nutrition availability in the surface ocean. Here, we report that Corexit alone can significantly inhibit DOM microgel formation and reduce the stability of pre-existing microgels. However, Corexit and oil, Chemically Enhanced Water Accommodated Fraction (CEWAF), could effectively facilitate DOM microgel formation. The unanticipated disturbance of Corexit and oil spills on the critical DOM-POM continuum warrant particular caution and thus should be considered for future application of Corexit during oil spills.

Scarce studies have been published reporting field measurements of nitrous oxide (N2O) emissions from vineyards, particularly for European conditions. The aim this study was to assess the effect of conventional tillage and no-tillage cover crops on direct N2O emission factor from vineyards (Vitis vinifera L.) in Portugal. A two-year field study was carried out in central Portugal (Nelas, Portugal). The experiment was established in a mature non-irrigated vineyard. The following four treatments with three replications were considered: soil tillage of the inter-row (Till), treatment Till followed by application of mineral fertiliser (50 kg N ha−1) (Till + N), permanent resident vegetation in the inter-row (NoTill), and treatment No-Till followed by application of mineral fertiliser (50 kg N ha−1) (NoTill + N). The carbon dioxide (CO2) and N2O fluxes were measured by the closed chamber technique and analysed by gas chromatography during two consecutive growing seasons (Mars-September of 2015 and 2016) of the grapevine crop. The results showed that the average direct N2O EF for vineyards managed with conventional soil tillage in the inter-row was 0.57 ± 0.12% of N input and cover cropping by permanent resident vegetation in the inter-row reduces N2O emission in 60% (0.23 ± 0.29% of N input). Thus, the vineyard cover cropping was recommended as mitigation measure in order to reduce N2O emissions. The defaults direct N2O EF currently recommended by IPCC was not appropriated for vineyards and N2O emissions are currently potentially overestimated in the Portuguese inventory.

Trace element poisoning remains a great threat to various waterfowl and waterbirds throughout the world. In this study, we determined the trace element exposure of herbivorous whooper swans (Cygnus cygnus) wintering in Swan Lake (Rongcheng), an important swan protection area in northern China. A total of 70 samples including abiotic factors (seawater, sediments), food sources (seagrass, macroalgae), feathers and feces of whooper swans were collected from the marine lagoon during the winters of 2014/2015 and 2015/2016. Concentrations of Cu, Zn, Pb, Cr, Cd, Hg and As were determined to investigate the trace element exposure of whooper swans wintering in the area. Results showed that there was an increasing trend in sediment trace element concentrations, compared with historical data. The trace element concentrations in swan feces most closely resembled those of Zostera marina leaves, especially for Cd and Cr. The Zn and Hg concentrations in the swan feces (49.57 and 0.01mg/kg, respectively) were lower than the minimum values reported in the literature for other waterfowls, waterbirds and terrestrial birds. However, the concentrations of the other five trace elements fell within the lower and mediate range of values reported for birds across the world. These results suggest that the whooper swans wintering in Swan Lake, Rongcheng are not suffering severe trace element exposure; however, with the increasing input of trace elements to the lagoon, severe adverse impacts may occur in the future, and we therefore suggest that the input of trace elements to this area should be curbed.

Based on the remote sensing retrieval of PM2.5 concentration data in the long-time series, both the linear regression and grey system correlation analysis methods were employed to analyze the spatial and temporal pattern, variation trend and the main influencing factors of PM2.5 concentration in China from 1998 to 2014. The results showed that only 16.21%–24.67% of the land area in China PM2.5 concentrations reached the annual average criterion value of 10 μg/m3 set by the World Health Organization (WHO) in 1998–2014; the PM2.5 concentrations were greater than 95 μg/m3 mainly in Xinjiang Taklimakan Desert, west of Tianjin and the central region of Hebei. PM2.5 concentration was less than 10 μg/m3 mainly in Tibet, western Sichuan, northeastern Yunnan, Taiwan, northern Xinjiang, northern Inner Mongolia and northwest of Heilongjiang. High PM2.5 concentration in the northwest of China was mainly affected by sand and dust, while it was mainly caused by human activities in the eastern region. Except for Taiwan, low PM2.5 concentration areas were mainly located in the economically backward regions. The positive indicators in highly correlation with PM2.5 concentration include the average temperature, the proportion of primary and secondary industry to GDP, industrial consumption, the proportion of fulfilled amount of investment in real estate development to GDP, SO2 emissions and population density. The negative indicators in highly correlation with PM2.5 concentration include the average precipitation, the average wind velocity, the proportion of the tertiary industry to GDP, and the greening coverage rate of the built-up areas.

Aquatic invasive species (AIS) are biological pollutants that cause detrimental ecological, economic, and human-health effects in their introduced communities. With increasing globalization through maritime trade, ports are vulnerable to AIS exposure via commercial vessels. The Cuban Port of Mariel is poised to become a competitive transshipment hub in the Caribbean and the intent of this study was to evaluate present and potential impacts AIS pose with the likely future increase in shipping activity. We utilized previous assessment frameworks and publicly accessible information to rank AIS by level of threat. Fifteen AIS were identified in Cuba and one, the Asian green mussel Perna viridis (Linnaeus, 1758), had repeated harmful economic impacts. Five species associated with trade partners of Port Mariel were considered potentially detrimental to Cuba if introduced through shipping routes. The results presented herein identify species of concern and emphasize the importance of prioritizing AIS prevention and management within Cuba.

Sources of heavy metals pollution in the Burullus Lagoon include phosphate fertilizers, sewage and oil spills from fishing boats.The benthic species identified in this lagoon are Adelosina carinata striata (Wiesner), Quinqueloculina bosciana (d'Orbigny), Quinqueloculina seminulum (Linnaeus), Ammonia tepida (Cushman), Elphidium excavatum (Terquem). A. tepida is the most dominant species in the lagoon. It constitutes more than 97% of the total benthic foraminiferal assemblages reflecting tolerance to the very low salinity in the Burullus Lagoon.The intensity of deformation was severe exhibiting a peculiar change in the coiling direction in A. tepida with increase in cadmium concentration. A. tepida exhibited a great morphological variability and the recorded morphological abnormalities show high spire giving the spiroconvex test, additional chamber, aberrant chamber shape and size, twisted tests with elongated axes of rotation and complex deformities, whereas E. excavatum showed additional calcite secretion (tumors).