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The revealed preferences of Baltic Sea governments: Goals, policy instruments, and implementation of nutrient abatement measures
2017
Elofsson, Katarina | von Brömssen, Claudia
Nitrogen and phosphorus loads are considered a major reason for the eutrophication of the Baltic Sea. Until now, most of the abatement has been made at point sources while the implementation of policies for nonpoint sources has not led to equally large reductions in emissions. The purpose of this study is to investigate the determinants of how nutrient abatement measures are implemented by countries in the agricultural sector of the Baltic Sea region. We investigate how goal setting, policy instrument choice, and the level of implementation is determined by characteristics of the abatement measure as well as socio-economic characteristics of the country where it is implemented. Econometric analysis of a cross-sectional data set suggests that income, institutional capacity, and economies of scope in abatement and enforcement are important determinants of policies developed and their implementation.
Afficher plus [+] Moins [-]In situ elemental characterisation of marine microplastics by portable XRF
2017
Turner, Andrew
The performance of a portable x-ray fluorescence spectrometer configured in a test stand and coupled to a laptop has been evaluated for the determination of various elements (including Br, Cd, Cl, Cr, Cu, Fe, Pb and Zn) in beached microplastics. Under laboratory conditions, analysis of samples that covered the 3-mm x-ray beam returned concentrations that, on average, were within 20% of concentrations determined by ICP following acid digestion. Analysis of progressively smaller offcuts (to <1mm) resulted in corresponding concentrations that were comparable to those determined in original samples but errors and detection limits that progressively increased. When the configuration was deployed in situ with two operators, up to 35 microplastics counted for 60s each could be processed per hour. Advantages of immediate measurements include the development of an iterative study strategy, rapid compliance-evaluation, and identification of specific materials for further characterisation or study in the laboratory.
Afficher plus [+] Moins [-]Evaluation of indoor/outdoor urban air pollution by magnetic, chemical and microscopic studies
2017
Jeleńska, M. | Górka-Kostrubiec, B. | Werner, T. | Kądziałko-Hofmokl, M. | Szczepaniak-Wnuk, I. | Gonet, T. | Szwarczewski, P.
The paper presents comparison of outdoor and indoor air pollution by means of magnetic characteristics of dust settled on the floor indoors (ID) and particulate matter (PM) gathered outdoor on air filters. Samples were collected for one year period in three different locations in Warsaw, Poland. PM was collected in samplers placed at the yard of buildings and ID was collected inside these buildings using a vacuum cleaner. The magnetic methods supplemented by chemical elements analysis and microscope observations were applied to identification of magnetic mineralogy, concentration and grain-size of magnetic fraction and morphology and shape of particles.The results demonstrated differences in magnetic mineralogy and in grain-size distribution between PM and ID. The magnetite was the main magnetic phase in PM and magnetite with metallic iron in ID. The ratios of hysteresis parameters for PM and ID were located in different areas on Day-Dunlop diagram; PM data in the area for PSD magnetite and fine SP grains and ID data around SD + MD mixing curves for magnetite.The difference in magnetic mineralogy, especially the lack of metallic iron in PM, can be explained by the limitation of dust samplers that cannot collect grains larger than roughly 50 μm due to our microscopic observations. PM samplers collect population of dust with smaller grain size than vacuum cleaner or simple sweeping of a floor. The difference in granulometry and outdoor/indoor sources could be one of the reasons for which we did not observed the simple relation between magnetic susceptibility of ID and PM.
Afficher plus [+] Moins [-]Nowhere safe? Exploring the influence of urbanization across mainland and insular seashores in continental Portugal and the Azorean Archipelago
2017
Bertocci, Iacopo | Arenas, Francisco | Cacabelos, Eva | Martins, Gustavo M. | Seabra, Maria I. | Álvaro, Nuno V. | Fernandes, Joana N. | Gaião, Raquel | Mamede, Nuno | Mulas, Martina | Neto, Ana I.
Differences in the structure and functioning of intensively urbanized vs. less human-affected systems are reported, but such evidence is available for a much larger extent in terrestrial than in marine systems. We examined the hypotheses that (i) urbanization was associated to different patterns of variation of intertidal assemblages between urban and extra-urban environments; (ii) such patterns were consistent across mainland and insular systems, spatial scales from 10scm to 100skm, and a three months period. Several trends emerged: (i) a more homogeneous distribution of most algal groups in the urban compared to the extra-urban condition and the opposite pattern of most invertebrates; (ii) smaller/larger variances of most organisms where these were, respectively, less/more abundant; (iii) largest variability of most response variables at small scale; (iv) no facilitation of invasive species by urbanization and larger cover of canopy-forming algae in the insular extra-urban condition. Present findings confirm the acknowledged notion that future management strategies will require to include representative assemblages and their relevant scales of variation associated to urbanization gradients on both the mainland and the islands.
Afficher plus [+] Moins [-]Coral benchmarks in the center of biodiversity
2017
Licuanan, W.Y. | Robles, R. | Dygico, M. | Songco, A. | van Woesik, R.
There is an urgent need to quantify coral reef benchmarks that assess changes and recovery rates through time and serve as goals for management. Yet, few studies have identified benchmarks for hard coral cover and diversity in the center of marine diversity. In this study, we estimated coral cover and generic diversity benchmarks on the Tubbataha reefs, the largest and best-enforced no-take marine protected area in the Philippines. The shallow (2–6m) reef slopes of Tubbataha were monitored annually, from 2012 to 2015, using hierarchical sampling. Mean coral cover was 34% (σ±1.7) and generic diversity was 18 (σ±0.9) per 75m by 25m station. The southeastern leeward slopes supported on average 56% coral cover, whereas the northeastern windward slopes supported 30%, and the western slopes supported 18% coral cover. Generic diversity was more spatially homogeneous than coral cover.
Afficher plus [+] Moins [-]Spatial and temporal distribution of mercury and methylmercury in bivalves from the French coastline
2017
Briant, N | Chouvelon, T | Martinez, L | Brach-Papa, C | Chiffoleau, JF | Savoye, N | Sonke, J | Knoery, J
Marine mercury (Hg) concentrations have been monitored in the French coastline for the last half a century using bivalves. The analyses presented in this study concerned 192 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from 77 sampling stations along the French coast and in the French Antilles sea. The goals of this study were to assess MeHg levels in various common bivalves from French coastline, and to identify possible geographic, taxonomic or temporal variations of concentrations. We show that the evolution of methylmercury (MeHg) concentrations covary with total mercury (HgT) concentrations. Moreover, in most of the study sites, HgT concentrations have not decreased since 1987, despite regulations to decrease or ban mercury used for anthropic activities.
Afficher plus [+] Moins [-]Relative sensitivity of Arctic species to physically and chemically dispersed oil determined from three hydrocarbon measures of aquatic toxicity
2017
Bejarano, Adriana C. | Gardiner, William W. | Barron, Mace G. | Word, Jack Q.
The risks to Arctic species from oil releases is a global concern, but their sensitivity to chemically dispersed oil has not been assessed using a curated and standardized dataset from spiked declining tests. Species sensitivity to dispersed oil was determined by their position within species sensitivity distributions (SSDs) using three measures of hydrocarbon toxicity: total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbon (PAHs), and naphthalenes. Comparisons of SSDs with Arctic/sub-Arctic versus non-Arctic species, and across SSDs of compositionally similar oils, showed that Arctic and non-Arctic species have comparable sensitivities even with the variability introduced by combining data across studies and oils. Regardless of hydrocarbon measure, hazard concentrations across SSDs were protective of sensitive Arctic species. While the sensitivities of Arctic species to oil exposures resemble those of commonly tested species, PAH-based toxicity data are needed for a greater species diversity including sensitive Arctic species.
Afficher plus [+] Moins [-]Adsorption of 17 α-ethyl estradiol with the competition of bisphenol A on the marine sediment of Hong Kong
2017
Fei, Ying-heng | Leung, Kenneth M.Y. | Li, Xiao-yan
The present experimental study was to characterize the adsorption behavior of 17 α-ethyl estradiol (EE2) onto marine sediment in both the single and binary solute systems. Stepwise spiking was innovatively performed to better understand the competition effects. Adsorption of EE2 on the marine sediment can be well fitted by the Freundlich model with an affinity coefficient (KF) varying from 15.8 to 39.8L/kg. It was significantly influenced by SOM and the particle properties. Co-presence of BPA brought about a significant competition effect on the adsorption of EE2, leading to a reduced EE2 adsorption. The competitive effect imposed by EE2 to BPA, however, was even more serious owing probably to the large molecular structure and high hydrophobicity of EE2. The sediment sample with the highest SOM and SSA presented a mild competition effect, while the sediment with the lowest SOM and largest particle size exhibited the most serious competition effect.
Afficher plus [+] Moins [-]Are shipwrecks a real hazard for the ecosystem in the Mediterranean Sea?
2017
Renzi, Monia | Romeo, Teresa | Guerranti, Cristiana | Perra, Guido | Canese, Simonepietro | Consoli, Pierpaolo | Focardi, Silvano E. | Berti, Claudio | Sprovieri, Mario | Gherardi, Serena | Salvagio, Daniela | Giaramita, Luigi | Esposito, Valentina | Battaglia, Pietro | Giacobbe, Salvatore | Andaloro, Franco
The aim of the present study was to evaluate the hazard from shipwrecks on communities by a holistic approach taking into account different effects on biological communities. Multibeam and Remotely Operated Vehicles surveys recorded ecological assessment of fish and benthic species on three shipwrecks flooded during the Second World War on Maërl beds habitats in the strait of Sicily. Pollution levels of a wide range of chemicals of ecotoxicological concern were also measured in sediments and in fish species from different trophic levels. Statistical analysis evidenced significant differences among pollutant levels between both sediments and fish collected in shipwreck sites and controls. Concerning fish, significant effects due to the vessel's cargo type and flooding position are recorded. In spite of that, our results underline that shipwrecks are also a hotspots of biodiversity and a habitat for preservation strategies in marine ecosystems that need to be monitored.
Afficher plus [+] Moins [-]Observations of aerosol color ratio and depolarization ratio over Wuhan
2017
Liu, Boming | Ma, Yingying | Gong, Wei | Zhang, Ming
The aerosol color ratio, depolarization ratio and aerosol optical depth (AOD) were measured by a two-wavelength-depolarization lidar at Wuhan, China during the period from May 2015–July 2016. The annual average AOD at Wuhan was about 0.33 during the period 2015–2016. The seasonal average AOD is small (0.26 ± 0.25) during the winter (December–February) season and large (0.4 ± 0.1) during the summer (June–August) season. The monthly average color ratio is small (0.23 ± 0.09) in January and large (0.76 ± 0.21) in August with an annual average value 0.54. The maximum monthly mean depolarization ratio (0.2 ± 0.07) occurred in the month of October, while the minimum (0.06 ± 0.02) occurred in the month of September, and the annual mean depolarization ratio was about 0.17. An analysis of temporal variations of color ratio and depolarization ratio suggests the presence of coarse and non-spherical particles during the autumn. The aerosol color ratio between 0.3 and 2.0 km was large (0.65), suggesting a large number of coarse particles in this range. The vertical distribution of the depolarization ratio is uniform. Finally, the spatial aerosol distribution under different weather conditions and its relationship with the color ratio is investigated in detail. The color ratio value of 0.74 could be used as a threshold for distinguishing polluted weather from clean weather. The aerosol optical and physical properties are investigated to provide a comprehensive understanding of aerosol radiative forcing and environmental problems in this region.
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