Nickel and chromium accumulation from the air in Italian ryegrass (Lolium multiflorum L.) is presented in this paper. Plants were exposed at five sites varying in environmental characteristics. Four one-month series were performed during the 2011 and 2012 growing seasons. Chromium and nickel concentrations in leaves were analysed after every series and compared to control plants. The lowest levels of both trace elements were found in samples collected from control sites. Canonical variate analysis revealed differences among sites and the control, and on this basis we found the lowest values in the suburban area. The lowest trace element concentrations of Cr in leaves were observed at the beginning of the growing season and the highest from mid-June to mid-August, while Ni concentrations varied among series and years. Accumulation of both trace elements in Italian ryegrass was at a comparable level or lower than results obtained in similar investigations in other countries. Moreover, the higher concentrations of both elements were probably connected with increased traffic and elevated small industry activities in urban and rural areas.

In this study, the suspended particulate matter (SPM) of the Yellow River (Huanghe) was collected biweekly at the outlet and analyzed for particulate trace element contents. The seasonal variations of the trace elements were primarily controlled by hydrological processes, which determined different sources of the SPM. Moreover, As, Co, Cr, and Ni primarily originated from lithogenic sources, whereas Cd, Cu, Pb and Zn were influenced by anthropogenic activities. The Yellow River has suffered moderate to considerable ecological risk during the late stage of Water and Sediment Regulation (WSR). Using the discharge-weighted contents method, the annual trace element fluxes were estimated, with ca. 30% of the annual fluxes occurring within the short WSR period (6% of one year). More specifically, 75% of the Cd flux was from an anthropogenic source, which likely posed a significant threat to the estuary and the adjacent coastal ecosystems.

The risks of heavy metal in Futian mangrove forest sediment were assessed using the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) methods. The results indicated that AVS distributions were more variable than the SEM distributions at all 16 sampling sites. The positive correlation between AVS and SEM indicated that their similar formative and existing conditions and that AVS acted as an important carrier for SEM. The major SEM component was Zn (69.7.3–94.2%), whereas the Cd contribution (the most toxic metal present) to SEM was no more than 1%. The possible adverse effects caused by heavy metals at ten sampling sites may be due to higher levels of SEMs, rather than AVSs. The total organic carbon (TOC) was an important metal-binding phase in the sediments. Taking into account the TOC concentration, there were no adverse effects due to heavy metals in any of the Futian mangrove forest sediments.

Sequential extraction study was performed to determine the concentrations of non-residual metal-complexes in the mangrove sediments from the Divar Island, (west coast of India). Accumulation of metal in the mangrove roots (from the same location) was determined and used as an indicator of bioavailability of metal. An attempt was made to establish a mechanistic linkage between the non-residual metal complexes and their bioavailability in the mangrove system. The non-residual fractions of Cu and Ni were mainly associated with Fe/Mn oxyhydroxide and organic phases in the sediments. A part of these metal fractions were bioavailable in the system. These two phases were the major controlling factors for Ni speciation and their bioavailability in the studied sediments. However, Cu was found to interact more strongly with the organic phases than Ni in the mangrove sediments. Organic phases in the mangrove sediments acted as buffer to control the speciation and bioavailability of Cu in the system.

Organochlorine pesticides (OCPs) residues were determined in fillets of Lutjanus colorado, L. argentiventris, and L. novemfasciatus. Fillet samples were collected bimonthly from February 2012 to February 2013. OCPs average concentrations do not differ significantly according to size, weight, or season, nor do they relate with the physico-chemical parameters of the sea water. The highest concentration and most frequently encountered OCPs were endosulfan sulfate, δ-HCH, and heptachlor epoxide, which indicates their use in the recent past and confirms their persistence. Average concentrations of ∑HCHs, ∑chlordane, and ∑heptachlor in samples were above cancer MRLs according to data from monthly consumed portions. HCHs and heptachlor are listed in Appendix III of the Rotterdam Convention of chemicals placed on a prior informed consent procedure for import and export purposes; they are considered illegal in Mexico. The OCPs concentrations above cancer MRLs in Lutjanus spp. turn its frequent consumption into a human health risk.

Fiddler crabs Uca rapax were analyzed in three mangrove areas located in both a lagoon and estuarine system in order to study the influence of eutrophication on their population dynamics and production. Populations at the three sites showed a biased sex ratio. Densities were similar at the three sites, but biomass was higher at the lagoon system. Despite biomass being higher at the most eutrophic site, this site exhibited the lowest production. Regarding age structure, the population inhabiting the less eutrophic site mainly comprised younger crabs. The lower production and smaller P/B ratio found in the more eutrophic site were most likely consequences of a high mortality rate and an aged population. Our study evidences the high plasticity of the fiddler crab U. rapax, and confirms secondary production and P/B ratio estimates as useful tools to assess the effects of environmental change.

This study investigates the economic consequences of the nutrient load reductions agreed in the 2013 revision of the Baltic Sea Action Plan. The cost of meeting the targets set for waterborne sources was estimated to be 1980 MEUR annually. The 2013 revision is a step towards cost-efficient water protection: the cost of meeting the earlier targets would have been 328 MEUR (14%) higher, although the revised targets are now more ambitious with respect to phosphorus. We demonstrate that there is potential for efficiency gains by introducing flexibility mechanisms, such as ‘joint implementation’ to trans-boundary water protection. The potential gains can be as high as 280 MEUR (14%). The most flexible interpretation of the basin targets, one allowing Contracting Parties to account for reductions in other sea basins in proportion to their effect in the focal basin, could further reduce the total cost by 200 MEUR (12%).

Glyphosate-based herbicides are extensively used and can be measured in aquatic ecosystems, including coastal waters. The effect of glyphosate on non-target organisms is an issue of worldwide concern. The aim of this study was to investigate the effects of subchronic exposure to glyphosate in juvenile oysters, Crassostrea gigas. Yearling oysters were exposed to three concentrations of glyphosate (0.1, 1 and 100μgL−1) for 56days. Various endpoints were studied, from the individual level (e.g., gametogenesis and tissue alterations) to the molecular level (mRNA quantification), including biochemical endpoints such as glutathione-S-transferase (GST) and catalase activities and malondialdehyde content. No mortality and growth occurred during the experiment, and individual biomarkers revealed only slight effects. The levels of gene expression significantly increased in oysters exposed to the highest glyphosate concentration (GST and metallothioneins) or to all concentrations (multi-xenobiotic resistance). These results suggested an activation of defence mechanisms at the molecular level.

This works intends to evaluate the impacts of the national emission ceilings (NEC) reduction scenarios on the air quality in Portugal, verifying the fulfillment of the air quality thresholds for 2020. The air quality numerical modeling system WRF–EURAD was applied to this 2020 future scenario and results were compared to the present situation -year 2012. This modeling system was already evaluated for Portugal domain in previous studies, by comparison with measured air quality data, and showed reasonable skills for all the pollutants. This system was applied over the Continental domain of Portugal, using nesting approach, with a horizontal resolution of 5x5km2, for both scenarios conditions (2012 and 2020) considering the respective emissions data and assuming the 2012 meteorological conditions. The results point towards an improvement of the air quality over Continental Portugal, in particular for particulate matter (in the urban areas of Lisbon and Porto) and SO2 (near specific industrial sources) but do not solve the non–compliance status regarding the O3 threshold value for protection of human health. These results strengthen the importance of including the NEC emission scenarios in the air quality national strategy, but additional mitigation actions need to be designed, with focus on ozone and its precursors, at local and regional scale.

Remediation of soil and groundwater contaminated with toxic metals has been a major environmental challenge for decades. Yet, cost-effective and sustainable in situ remediation technologies remain lacking. Over the last 15 years or so, an innovative in situ remediation strategy has shown promising by means of stabilized nanoparticles. Stabilized nanoparticles are prepared using novel stabilizers that facilitate the deliverability and transport of nanoparticles in the subsurface. This study reviews synthesis and characterization of some model stabilized nanoparticles and their application for remediation of metal-contaminated soil and water. Fate and transport of these stabilized nanoparticles in groundwater and soil are also examined. Lastly, this review identifies the key knowledge gaps such as lack of field data pertaining to the long-term effectiveness of the immobilized metals and impacts of the delivered nanoparticles on the biogeochemical conditions in the subsurface. The information may facilitate further development of this promising remediation technology.