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Levels of chemicals in two fish species from four Italian fishing areas Texto completo
2016
Guerranti, Cristiana | Grazioli, Eleonora | Focardi, S. (Silvano) | Renzi, Monia | Perra, Guido
This paper reports the results of an assessment of contamination by polychlorinated biphenyls and polycyclic aromatic hydrocarbons in two demersal species of commercial importance. The organisms considered were Mullus barbatus and Engraulis encrasicolus from three marine areas off the Italian coasts: North and South Adriatic Sea and North Tyrrhenian Sea. The instrumental analyzes have revealed, in many samples examined, the presence of most of PCB congeners and 5 of the 16 PAHs considered. Organisms caught in the waters of Apulia have greater contamination values, while the samples from Tuscany showed the lowest ones, results probably referable to the environmental quality differences between the areas of origin, at least for PAHs, since the sampling areas are represented respectively by areas with presence of oil extraction plant (Adriatic), and by an area subject to environmental protection.
Mostrar más [+] Menos [-]Is existing legislation fit-for-purpose to achieve Good Environmental Status in European seas? Texto completo
2016
Boyes, Suzanne J. | Elliott, Michael | Murillas-Maza, Arantza | Papadopoulou, Nadia | Uyarra, Maria C.
Recent additions to marine environmental legislation are usually designed to fill gaps in protection and management, build on existing practices or correct deficiencies in previous instruments. Article 13 of the European Marine Strategy Framework Directive (MSFD) requires Member States to develop a Programme of Measures (PoM) by 2015, to meet the objective of Good Environmental Status (GES) for their waters by 2020. This review explores key maritime-related policies with the aim to identify the opportunities and threats that they pose for the achievement of GES. It specifically examines how Member States have relied on and will integrate existing legislation and policies to implement their PoM and the potential opportunities and difficulties associated with this. Using case studies of three Member States, other external impediments to achieving GES are discussed including uses and users of the marine environment who are not governed by the MSFD, and gives recommendations for overcoming barriers.
Mostrar más [+] Menos [-]Fate, behaviour and weathering of priority HNS in the marine environment: An online tool Texto completo
2016
Cunha, Isabel | Silva, Helena Oliveira da | Neuparth, Teresa | Torres, Tiago | Santos, Miguel Machado
Literature data and data obtained with modelling tools were compiled to derive the physicochemical behaviour of 24 priority Hazardous and Noxious Substances (HNS), as a proxy to improve environmental, public health and political issues in relation to HNS spills. Parameters that rule the HNS behaviour in water and those that determine their distribution and persistence in the environment, such as fugacity, physicochemical degradation, biodegradation, bioaccumulation/biotransformation and aquatic toxicity, were selected. Data systematized and produced in the frame of the Arcopol Platform project was made available through a public database (http://www.ciimar.up.pt/hns/substances.php). This tool is expected to assist stakeholders involved in HNS spills preparedness and response, policy makers and legislators, as well as to contribute to a current picture of the scientific knowledge on the fate, behaviour, weathering and toxicity of priority HNS, being essential to support future improvements in maritime safety and coastal pollution response before, during and after spill incidents.
Mostrar más [+] Menos [-]Analysis of the TSP, PM10 concentrations and water-soluble ionic species in airborne samples over Sistan, Iran during the summer dusty period Texto completo
2016
Dahmardeh Behrooz, Reza | Esmaili-Sari, Abbas | Bahramifar, Nader | Kaskaoutis, D.G.
The present study analyzes the total suspended particulates (TSP) and particulate matter less than 10 μm (PM10) concentrations along with the water-soluble ionic species (WSIS) in airborne dust samples collected in Zabol, located in the Sistan basin of southeast Iran. Rather extreme TSP and PM10 mean concentrations of 1867.0 μg m−3 and 433.4 μg m−3 are found, while the WSIS contribute only 8.9% and 19.3% to the TSP and PM10 mass, respectively indicating large fraction of water-insoluble crustal elements, carbonaceous aerosols and heavy metals that remained unexplored. Ca2+ is the most abundant ionic species contributing ∼25–26% to the total WSIS mass, followed by NH4+, K+, and SO42−. Important fractions of Cl− and Na+ (7–9% of the total WSIS mass) indicate the presence of saline dust storms over Sistan due to desiccation of the Hamoun lakes and uplift of evaporated minerals by the strong Levar (120-days) wind. High correlations between the WSIS suggest large possibility for formation of NaCl, (NH4)2SO4, MgSO4, K2SO4, CaSO4 and NH4NO3. The dusty days (visibility < 2 km) are associated with intense winds (11.7 ms−1 on average) and large increase (∼80–100%) in the concentrations of the crustal elements (e.g., Ca2+, Mg2+ and Cl−) compared to the normal days, while the TSP and PM10 concentrations reach to 4496 μgm−3 and 1010.6 μgm−3, respectively.
Mostrar más [+] Menos [-]Trilateral association between SO2/NO2 emission, inequality in energy intensity, and economic growth: A case of Indian cities Texto completo
2016
Sinha, Avik
Interaction between environmental degradation and economic growth is a growing matter of interest among policymakers. This paper examines the trilateral association between SO2 and NO2 emission, inequality in energy intensity, and economic growth by using simultaneous-equation panel data models for a panel of 139 Indian cities over the period 2001–2013. Our results indicate that there is evidence of feedback hypothesis between NO2 and SO2 emissions and economic growth, economic growth and inequality in energy intensity, and NO2 and SO2 emissions and inequality in energy intensity. The results also verified the existence of Environmental Kuznets curve for both of the pollutants. These results are of interest to environmental and economic policymakers as these can help in coming up with economic policies to ensure environmental sustainability and an inclusive economic growth.
Mostrar más [+] Menos [-]Effect of temporal and spatial variability on the classification of the Ecological Quality Status using the CARLIT Index Texto completo
2016
Cavallo, Marianna | Torras, Xavier | Mascaró, Oriol | Ballesteros, Enric
Methodologies developed by European Member States to assess the environmental quality of their coastal waters under the EU Water Framework Directive (WFD, 2000/60/EC) may have an associated source of uncertainty. Here we identify and quantify the level of uncertainty in the CARLIT (Cartography of littoral and upper-sublittoral communities) methodology to test its effectiveness and reliability. The outcomes show that the effect of temporal variability (among years) within each water body is low when CARLIT is performed every year along the entire rocky coast. The spatial variability within a water body is also low. According to these results, CARLIT could be performed every 3years across all the water body or, alternatively, every year considering at least 60% of each water body, without a significant reduction of the confidence in the classification of the Ecological Quality Status (EQS).
Mostrar más [+] Menos [-]Uncertainties in Atmospheric Mercury Modeling for Policy Evaluation Texto completo
2016
Kwon, Sae Yun | Selin, Noelle E.
Mercury (Hg) contamination is an issue of a growing environmental and public health concern. Atmospheric chemistry transport models for Hg are a critical tool for understanding the sources, processes, and fate of Hg. Uncertainties in multiple aspects of atmospheric Hg models, however, limit their application for policy evaluation and for monitoring global trends in atmospheric Hg concentrations. This review aims to identify uncertainties in atmospheric Hg modeling that are relevant in the context of policy and for informing decision-making. We focus on specific requirements of the Minamata Convention on Mercury, a global treaty signed in 2013 to protect human health and the environment from Hg, to demonstrate how existing uncertainties in atmospheric Hg modeling can influence our ability to evaluate source-receptor relationships. Modeling studies of source attribution suggest that major uncertainties in atmospheric Hg modeling arise from anthropogenic emissions, biogeochemical cycling, and atmospheric chemistry. Uncertainties in these aspects of modeling are expected to increase under the Convention, with regulation of anthropogenic emissions, changes in atmospheric conditions, and legacy and natural Hg source contribution to the global biogeochemical cycle. These uncertainties can interact with one another and with the current Hg species measurement capability and pose challenges to effectively monitoring trends in atmospheric Hg. Developing additional means to attribute simulated atmospheric Hg trends and improve source-receptor relationships in atmospheric Hg models would improve our ability to evaluate the Convention’s effectiveness.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the intertidal zone of Bohai Bay, Northeast China: Spatial distribution, composition, sources and ecological risk assessment Texto completo
2016
Qian, Xiao | Liang, Baocui | Fu, Wenjun | Liu, Xinhui | Cui, Baoshan
Polycyclic aromatic hydrocarbons (PAHs) can enter intertidal zones by various pathways and pose potential threats to intertidal ecosystem. We investigated distribution, composition, sources and risk assessment of PAHs in intertidal surface sediments of Bohai Bay. Total PAH concentrations ranged from 37.2ng·g−1 to 206.6ng·g−1, among which high values occurred near Nanpaishuihe River Estuary and Haihe River Estuary. The composition patterns of PAHs were characterized by the predominance of 3-ring and 4-ring PAHs, and acenaphthylene was the most dominant component. Diagnostic ratios and principal component analysis have confirmed that PAH contaminants originated from mixed sources, and the major was local combustion. The mean benzo(a)pyrene equivalent concentration of total PAHs in intertidal sediments was 15.67ng·g−1, which was mostly contributed by seven carcinogenic PAHs. According to ecological risk assessment, negative effects related to acenaphthylene would occur occasionally in partial survey regions of the study.
Mostrar más [+] Menos [-]Macondo oil in deep-sea sediments: Part 2 — Distribution and distinction from background and natural oil seeps Texto completo
2016
Stout, Scott A. | Payne, James R. | Ricker, Robert W. | Baker, Gregory | Lewis, Christopher
Following the Deepwater Horizon oil spill, the spilled Macondo oil was severely weathered during its transport within the deep-sea plume as discrete particles, which were subsequently deposited on the seafloor. The Macondo oil deposited in deep-sea sediments was distinguished from ambient (background) hydrocarbons and naturally-seeped and genetically-similar oils in the Mississippi Canyon region using a forensic method based upon a systematic, multi-year study of 724 deep-sea sediment cores collected in late 2010 and 2011. The method relied upon: (1) chemical fingerprinting of the distinct features of the wax-rich, severely-weathered Macondo oil; (2) hydrocarbon concentrations, considering a core's proximity to the Macondo well or to known or apparent natural oil seeps, and also vertically within a core; and (3) results from proximal cores and flocculent material from core supernatants and slurp gun filters. The results presented herein establish the geographic extent of “fingerprintable” Macondo oil recognized on the seafloor in 2010/2011.
Mostrar más [+] Menos [-]Comparison of partial extraction reagents for assessing potential bioavailability of heavy metals in sediments Texto completo
2016
Brady, James P. | Kinaev, Irina | Goonetilleke, Ashantha | Ayoko, G. A. (Godwin A.)
Assessment of heavy metal bioavailability in sediments is complex because of the number of partial extraction methods available for the assessment and the general lack of certified reference materials. This study evaluates five different extraction methodologies to ascertain the relative strengths and weaknesses of each method. The results are then compared to previously published work to ascertain the most effective partial extraction technique, which was established to dilute (0.75–1M) nitric acid solutions. These results imply that single reagent; weak acid extractions provide a better assessment of potentially bioavailable metals than the chelating agents used in sequential extraction methods.
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