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Sources of bathing water pollution in northern Tuscany (Italy): Effects of meteorological variables Texto completo
2017
Federigi, Ileana | Verani, Marco | Carducci, Annalaura
This study was carried out in a popular tourist destination located in Italy, where short-term pollution posed the problem of low quality status of bathing waters (according to European Directive) owing to the fecal contamination caused by drainage ditches. Our goal was to understand the role of meteorological conditions on freshwater and seawater bacterial indicator levels, and the impact of polluted streams on seawater contamination. To this aim, results from surface waters were analyzed during five bathing seasons, from 2011 to 2015. Our results demonstrated a relationship between bacterial densities and rainfall amount and a time-dependent dilution effect of the sea between the two halves of each bathing season. This analytical survey confirmed the strategic role of meteorological variables in bathing waters quality, and it could be a support for generation and development of predicting models of indicator levels for bathing area.
Mostrar más [+] Menos [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Texto completo
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Texto completo
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
To manage trace metal pollution it is critical to determine how much temporal trends can be attributed to local or large-scale sources. We tracked changes in metal content in the seagrass Posidonia oceanica, along the NW Mediterranean from 2003 to 2010. While Cu, Cd and Ni showed a large inter-site variation, likely due to local factors, Fe, Mn and Pb showed little local variation and synchronous interannual variability across sites, most likely due to large-scale sources. Zn showed equal importance of local and large-scale sources of variation. Temporal trends of Ni, Zn, Cd, Cu remained almost stable. In contrast, Fe, Mn and Pb slightly increased in the last decade. These trends suggest that metals like Cu, Cd, Ni can be effectively managed at local scale. Whereas, elements like Fe, Mn and Pb have an important large-scale component that needs to be managed across the frontiers of national jurisdictions.
Mostrar más [+] Menos [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea Texto completo
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
To manage trace metal pollution it is critical to determine how much temporal trends can be attributed to local or large-scale sources. We tracked changes in metal content in the seagrass Posidonia oceanica, along the NW Mediterranean from 2003 to 2010. While Cu, Cd and Ni showed a large inter-site variation, likely due to local factors, Fe, Mn and Pb showed little local variation and synchronous interannual variability across sites, most likely due to large-scale sources. Zn showed equal importance of local and large-scale sources of variation. Temporal trends of Ni, Zn, Cd, Cu remained almost stable. In contrast, Fe, Mn and Pb slightly increased in the last decade. These trends suggest that metals like Cu, Cd, Ni can be effectively managed at local scale. Whereas, elements like Fe, Mn and Pb have an important large-scale component that needs to be managed across the frontiers of national jurisdictions. | Agenda Catalana de l'Aigua [CV04000002] | Spanish Ministry of Science and Innovation [CTM2013-48027-C3.3-R, CTM2013-48027-C3-1-R] | Agenda de Gestic d'Ajuts Universitaris i de Recerca of Generalitat de Catalunya
Mostrar más [+] Menos [-]Characteristics of meso-sized plastic marine debris on 20 beaches in Korea Texto completo
2017
Lee, Jongsu | Lee, Jongmyoung | Hong, Sunwook | Hong, Sang Hee | Shim, Won Joon | Eo, Soeun
We surveyed the abundance and accumulation patterns of mesoplastic marine debris (5–25mm) on 20 beaches in Korea. The mean abundance of it was 13.2items/m2, and the mean weight was 1.5g/m2. Hard plastic and Styrofoam were the dominant types. The proportions of hard plastic and Styrofoam were highly variable among the beaches, each accounting for 0–100% of the total debris on a given beach with 32% and 48.5% (by number) on average, respectively. Relatively lower abundances of mesoplastic marine debris compared with our previous studies were likely due by differences of the sampling areas within the beach. The samples of this research were selected from backshore, middle line, and water edge whereas they were selected from high strandline and backshore in our previous studies. It should be considered when discussing the level of mesoplastic marine debris.
Mostrar más [+] Menos [-]Characterization of organic compounds in winter PM1 aerosols in a small industrial town Texto completo
2017
Křůmal, K. | Mikuška, P. | Večeřa, Z.
PM1 aerosol, collected during winter campaign in urban area situated close to a large automobile factory, was analysed on content of selected organic compounds, namely monosaccharide anhydrides, diterpenoids (including retene and resin acids), n-alkanes (including pristane and phytane), polycyclic aromatic hydrocarbons (including picene), monosaccharides, disaccharides, polyols, hopanes and steranes.Monosaccharide anhydrides (MAs, markers for biomass burning) were the most abundant organic compounds (the mean sum of concentration of 513 ng m−3). The sum of MAs constituted in average 70.0% of the mass of all analysed organic compounds and 1.91% of the PM1 mass. Diterpenoids, markers for softwood combustion, were the second most abundant analysed organic compounds (the mean concentration of 119 ng m−3). The mean concentrations of other studied organic compounds were smaller, namely saccharides 31.6 ng m−3, n-alkanes, including isoprenoids 35.3 ng m−3, PAHs 15.6 ng m−3 and hopanes, including one sterane 1.54 ng m−3.Combustion of solid fuels (coal and wood) for household heating was the dominant emission source of carbonaceous aerosols sampled during the campaign. The composition of aerosols collected in the studied locality was affected by local emissions and also by regional transport of polluted air from small villages nearby Mladá Boleslav.Two unit risks (WHO and CalEPA) were applied for the estimation of carcinogenic risk of PAHs exposure. The computed lifetime cancer risk at the studied locality during the campaign period was 1.93 × 10−4 (WHO unit risk) and 2.43 × 10−6 (CalEPA unit risk) on average. However, the real cancer risk for the lifetime exposure (70 years) is lower at the studied locality because our measurement lasted only 2 weeks in winter when the concentrations of PAHs were higher than in other seasons of the year.
Mostrar más [+] Menos [-]Blood and feather concentrations of toxic elements in a Baltic and an Arctic seabird population Texto completo
2017
Fenstad, Anette A. | Bustnes, Jan O. | Lierhagen, Syverin | Gabrielsen, Kristin M. | Öst, Markus | Jaatinen, Kim | Hanssen, Sveinn A. | Moe, Børge | Jenssen, Bjørn M. | Krøkje, Åse
We report blood and feather concentrations of elements in the Baltic Sea and Arctic population of common eiders (Somateria mollissima). The endangered Baltic Sea population of eiders was demonstrably affected by element pollution in the 1990s. While blood concentrations of Hg were higher in Baltic breeding eiders, blood Se, As and Cd concentrations were higher in Arctic eiders. Blood concentrations of Pb, Cr, Zn and Cu did not differ between the two populations. While blood Pb concentrations had declined in Baltic eiders since the 1990s, Hg concentrations had not declined, and were above concentrations associated with adverse oxidative effects in other bird species. Inconsistent with blood concentrations, feather concentrations suggested that Pb, Zn, and Cd exposure was higher in Baltic eiders, and that Hg exposure was higher in Arctic eiders. Our study thus emphasizes the need for comprehensive evaluation of toxic element status, covering the annual cycle of a species.
Mostrar más [+] Menos [-]Assessment of heavy metal and petroleum hydrocarbon contamination in the Sultanate of Oman with emphasis on harbours, marinas, terminals and ports Texto completo
2017
Jupp, Barry P. | Fowler, Scott W. | Dobretsov, Sergey | van der Wiele, Henk | Al-Ghafri, Ahmed
The assessment here includes data on levels of contaminants (petroleum hydrocarbons and heavy metals) in sediments and biomonitor organisms, including the eulittoral rock oyster Saccostrea cucullata and subtidal biomonitors, the barnacle Balanus trigonus and the antipatharian coral Antipathes sp., at harbours, marinas, terminals and large ports along the coastline of Oman. TBT levels in harbour and port sediments up to a maximum of 100ppb TBT dry weight are highlighted. Oysters contained concentrations up to 367ppm mg TPH/kg dry weight. The maximum levels of Cd, Cu, Pb and Zn were found in the subtidal sediments and barnacles at the oil tanker loading Single Buoy Mooring stations in Mina Al Fahal. In general, the levels of most of the contaminants analysed are at low to moderate concentrations compared to those in highly contaminated sites such as shipyards and dry docks, but continued monitoring is recommended especially during any dredging campaigns.
Mostrar más [+] Menos [-]Ecological Considerations of Per- and Polyfluoroalkyl Substances (PFAS) Texto completo
2017
McCarthy, Chris | Kappleman, William | DiGuiseppi, William
Per- and polyfluoroalkyl substances (PFASs) have been detected around the globe in drinking water, in various media at release sites, in human blood serum, and in non-human biota tissue. These compounds are emerging contaminants due to the rapidly evolving regulatory landscape, which is driven by advances in toxicological and risk assessment knowledge emanating from academia and government research organizations. A robust understanding of these developments is required to appreciate the basis, present state, and future direction of regulation and management of PFASs. This paper summarizes recent toxicological and ecological risk assessment information, ongoing research, and current guidelines governing PFASs for the protection of non-human biota.
Mostrar más [+] Menos [-]Prioritizing Process in Action Plans: a Review of Approaches Texto completo
2017
Licitra, Gaetano | Ascari, Elena | Fredianelli, Luca
PURPOSE OF THE REVIEW: The paper is focused on the prioritization process in noise action plans. The available indicators (noise scores) and methodologies for defining hotspots are analysed and discussed. Indicators and methodologies are classified in order to highlight their suitability for different specific aims. RECENT FINDINGS: The revised annex II of the European Directive 2002/49/EC fixed population exposure and modelling issues leading to different approaches in the prioritization process. Unfortunately, the indicators for rating areas are not commonly defined and a validated procedure is still not recognized at EU level. Furthermore, the importance of considering annoyance in the mitigation process arose, and this paper summarizes the pros and cons of their use for the purpose of prioritization process. A recent attempt to combine annoyance evaluations with limits compliance in noise score for the priority definition is presented. The paper classifies various priority indicators basing on their inclusion of compliance limits compliance, annoyance or both. Then, the methods for merging index values at dwelling for hotspot identification are classified according to their approaches, particularly between those using geometrical approaches, or needing reference administrative areas. The paper highlights the suitability of each method to specific sources, contexts and aims of the prioritization process. Merging methods resulted necessary whenever the epidemiological study is not the aim of the calculation; indeed, the mitigation measures could be planned for delimited and prioritized areas and not directly derived from building noise scores.
Mostrar más [+] Menos [-]Nitrogen Cycle in Engineered and Natural Ecosystems—Past and Current Texto completo
2017
Pappu, Aiswarya Rani | Bhattacharjee, Ananda Shankar | Dasgupta, Sunayna | Goel, Ramesh
Due to modern urbanization and rapid population growth, the nitrogen cycle has been significantly disturbed within differing ecosystems. Focusing specifically on imbalances present in an aquatic ecosystem, it is imperative that the wastewater engineering community addresses the need to conserve energy and resources better by developing more effective tools for application in wastewater treatment plants. The Academy of Engineers recently identified nitrogen cycle management as one of the 14 predominant challenges that engineers need to be addressing in the immediate future. This validates a definite sense of urgency to find practical solutions for implementation in wastewater treatment plants. In order to determine the best means for effective nitrogen cycle management, an in-depth examination of disturbances in the cycle provide an understanding of what is needed to resolve these issues. This article provides an in-depth discussion of past research, developments found in present studies, as well as providing potential strategies for improving the future of nitrogen cycle management.
Mostrar más [+] Menos [-]Duration rather than frequency of hypoxia causes mass mortality in ark shells (Anadara kagoshimensis) Texto completo
2017
Nakano, Tadashi | Yamada, Katsumasa | Okamura, Kazumaro
Hypoxia is associated with mass mortality in estuaries, but a direct causal relationship has not been proven to date. This study aimed to demonstrate this relationship and to evaluate how the duration of hypoxia affects the survival of ark shells (Anadara kagoshimensis) using mathematical modeling. The dissolved oxygen concentration was monitored at two stations in the innermost area of Ariake Bay, Japan, to calculate the duration of hypoxia. This was then included in a mathematical model to simulate the population density with sequential computation. The population density decreased with prolonged hypoxia, reaching a value close to the observed population density, indicating that hypoxia is the main cause of mass mortality in ark shells. Furthermore, the ark shell population disappeared in 8days with constant hypoxia but persisted when hypoxia was alternated with normoxia every 6 h. Therefore, mass mortality is caused by the duration rather than the frequency of hypoxia.
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