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.

Levels of polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NFRs) were measured in ambient outdoor air, indoor air and indoor dust collected in homes and offices at urban, semi-urban and rural locations in Istanbul, Turkey. Indoor air levels of Σ12PBDEs in homes and offices ranged from 36 to 730 pg/m3 and 160 to 10 100 pg/m3, respectively, while levels of Σ12NFRs ranged from 180 to 7600 pg/m3 and 180 to 42 400 pg/m3, respectively. Outdoor air levels ranged from 110 to 620 pg/m3 for Σ12PBDEs and 750 to 2800 pg/m3 for Σ12NFRs. I/O ratios that are greater than 1 suggest that air concentrations detected in indoor environments are mainly from indoor sources. Indoor dust levels in homes and offices of Σ12PBDEs ranged from 400 to 12 500 ng/g and 330 to 32 200 ng/g respectively and levels of Σ12NFRs ranged from 320 to 31 400 ng/g and 910 to 97 900 ng/g, respectively. The I/O ratios >1 for PBDEs and NFRs may indicate that emissions of these chemicals detected in homes and offices are mainly from indoor sources. Due to childrens' frequent hand-to-mouth behaviour, lower body weight and increased dust ingestion rate compared to adults, exposure rates to target chemicals for children were greater than those of adults. Based on median concentrations of chemicals of interest in dust and air samples from Istanbul, we estimate that exposure rates of children to PBDEs and NFRs are up to 160 times higher compared to adults but none of the estimated exposure rates results for children or adults were than the recommended daily oral reference dose values of certain analytes.

In this paper, we examined the ingestion of marine debris (MD) in South American fur seals (SAFS), Arctocephalus australis, found dead in coastal beaches of northern Argentina and southern Brazil. Seven percent of 133 SAFS analyzed presented marine debris in their stomach (n=10), with no differences between sampling countries (Brazil n=7, Argentina n=3) and sexes (female=3; male=6). However, significant differences were observed between ages classes, with MD exclusively present in stomach contents of young specimens. Plastics represents 90% of MD ingested by the SAFS, whereas regarding the source, fishery-related items (e.g. monofilament lines) were the main MD (70%), with a lesser proportion of packaging (e.g. pieces of bags). Low numbers but large size pieces of MD were found in each stomach affected. Negative effects on the individuals could not be fully evaluated. Therefore, the potential impacts of the marine debris to the SAFS deserve further elucidation.

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.

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.

Road traffic emission factors (EFs) are important parameters in managing air quality. Estimation typically requires data from advanced (and expensive) monitoring systems which remain unavailable in some regions (e.g. in developing countries). In this context, the use of simpler (lower-cost) systems may be more appropriate, but it is essential to guarantee the robustness of EF estimations. This article describes a methodology designed to estimate vehicle EFs from street canyon measurements of traffic fluxes, wind speed and direction, and pollutant concentration levels by using low-cost devices, all samples at a one-minute interval. We use different moving window filters (time periods) to average the raw measurements. Applying standard multiple linear regressions (MRL) and principal component regressions (PCR), we show that there is an optimal smoothing level that best relates traffic episodes and pollutant concentration measurements. An application for PM10's EFs on four vehicle categories of Havana's fleet shows a preference for PCR over MLR techniques since it reduced the collinearity effects that appear when traffic fluxes are naturally correlated between vehicle categories. The best regression fits (R > 0.5 and standard deviation of estimates < 15%) were obtained by averaging data between 40′ and 60’; within the boundaries of 95% confidence interval motorcycles have an EF = 111.1 ± 2.7 mg km−1 veh−1; modern, light vehicles have an EF = 90.6 ± 11.2 mg km−1 veh−1; old, light vehicles have an EF = 125.4 ± 18.5 mg km−1 veh−1 and heavy vehicles have an EF = 415.1 ± 31.2 mg km−1 veh−1. We showed that upgrading old light vehicles is a promising scenario for reducing PM10 air pollution in Havana by between 10 and 17%.

Eutrophication is a complex process and often associated with not only a change in overall algal biomass but also with a change in biodiversity. Common metrics of eutrophication (e.g., chlorophyll a), total nitrogen (TN) and phosphorus (TP) are not adequate for understanding biodiversity changes, especially those associated with harmful algal bloom (HAB) proliferations. Harmful algae can increase disproportionately with eutrophication, depending on which nutrients change and in what proportion. This paper challenges several classic paradigms in our understanding of eutrophication and associated biodiversity changes. The underlying message is that nutrient proportions and forms can alter biodiversity, even when nutrients are at concentrations in excess of those considered limiting. The global HAB problem is on a trajectory for more blooms, more toxins, more often, in more places. Our approach to management of HABs and eutrophication must consider the broader complexity of nutrient effects at scales ranging from physiological to ecological.

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This paper presents a novel operational oil spill modelling system based on HF radar currents, implemented in a northwest European shelf sea. The system integrates Open Modal Analysis (OMA), Short Term Prediction algorithms (STPS) and an oil spill model to simulate oil spill trajectories. A set of 18 buoys was used to assess the accuracy of the system for trajectory forecast and to evaluate the benefits of HF radar data compared to the use of currents from a hydrodynamic model (HDM). The results showed that simulated trajectories using OMA currents were more accurate than those obtained using a HDM. After 48h the mean error was reduced by 40%. The forecast skill of the STPS method was valid up to 6h ahead. The analysis performed shows the benefits of HF radar data for operational oil spill modelling, which could be easily implemented in other regions with HF radar coverage.

Microplastics in the world's oceans are a global concern due to the potential threat they pose to marine organisms. This study investigated microplastic abundance, distribution and composition in the Atlantic Ocean on a transect from the Bay of Biscay to Cape Town, South Africa. Microplastics were sampled from sub-surface waters using the underway system of the RV Polarstern. Potential microplastics were isolated from samples and FT-IR spectroscopy was used to identify polymer types. Of the particles analysed, 63% were rayon and 37% were synthetic polymers. The majority of microplastics were identified as polyesters (49%) and blends of polyamide or acrylic/polyester (43%). Overall, fibres (94%) were predominant. Average microplastic abundance in the Atlantic Ocean was 1.15±1.45particlesm−3. Of the 76 samples, 14 were from the Benguela upwelling and there was no statistically significant difference in microplastic abundance between upwelled and non-upwelled sites.