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Sources of bathing water pollution in northern Tuscany (Italy): Effects of meteorological variables 全文
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.
显示更多 [+] 显示较少 [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea 全文
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 全文
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.
显示更多 [+] 显示较少 [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea 全文
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
显示更多 [+] 显示较少 [-]Characteristics of meso-sized plastic marine debris on 20 beaches in Korea 全文
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.
显示更多 [+] 显示较少 [-]Isolation and characterization of PAH-degrading bacteria from the Eastern Province, Saudi Arabia 全文
2017
Oyehan, Tajudeen A. | Al-Thukair, Assad A.
Contaminated sediment samples were collected from the Eastern Province, Saudi Arabia for isolation of pyrene- and phenanthrene-degrading bacteria by enrichment method. Four isolates were morphologically characterized as Gram-negative rod strains and 16S rRNA sequence analysis revealed the isolates as closely related to Pseudomonas aeruginosa, P. citronellolis, Ochrobactrum intermedium and Cupriavidus taiwanensis. Degradation of the polycyclic aromatic hydrocarbons (PAHs) by the latter three strains was investigated in liquid cultures. Results of concentration reduction analyzed with gas chromatography show that P. citronellolis_LB was efficient in removing phenanthrene, degrading 94% of 100ppm in 15days while O. intermedium_BC1 was more efficient in pyrene-removal, degrading 62% in 2weeks. Furthermore, bacterial growth assessment using optical density and population counts revealed the latter as more suitable for microbial growth analysis in PAH-containing cultures. In conclusion, the isolated bacterial strains could be further developed for efficient use in biodegradation of PAH.
显示更多 [+] 显示较少 [-]Long-term changes in nutrients, chlorophyll a and their relationships in a semi-enclosed eutrophic ecosystem, Bohai Bay, China 全文
2017
Qiao, Yinhuan | Feng, Jianfeng | Cui, Shangfa | Zhu, Lin
As the representative semi-enclosed bay of China, Bohai Bay has experienced severe eutrophication in recent decades. Monitoring data from 1995 to 2013 were analysed by generalized additive models (GAMs) to explore the temporal variations in nutrients concentrations, nutrient ratios, chlorophyll a (Chl a) concentrations and the responses of Chl a to the changes in nutrients in the spring and summer. The results showed that dissolved inorganic nitrogen (DIN) decreased from 1995 to 2000 but increased after 2000 in both the spring and summer, and soluble reactive phosphorus (SRP) decreased while the molar nitrogen/phosphorus (N/P) ratios (DIN to SRP) increased over the last two decades. Generally, P-limited phytoplankton growth was observed in the spring and summer and DIN was identified as the main pollutant constituent in Bohai Bay. Furthermore, negative correlations were found between DIN and Chl a in summer in Bohai Bay.
显示更多 [+] 显示较少 [-]Are shipwrecks a real hazard for the ecosystem in the Mediterranean Sea? 全文
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.
显示更多 [+] 显示较少 [-]Trends of BTEX in the central urban area of Iran: A preliminary study of photochemical ozone pollution and health risk assessment 全文
2017
Hajizadeh, Yaghoub | Mokhtari, Mehdi | Faraji, Maryam | Mohammadi, Amir | Nemati, Sepideh | Ghanbari, Reza | Abdolahnejad, Ali | Fard, Reza Fouladi | Nikoonahad, Ali | Jafari, Negar | Miri, Mohammad
The Environmental Protection Agency (USEPA) has identified Benzene, Toluene, Ethylbenzene, and Xylene (BTEX) as hazardous air pollutants. In this study, BTEX sampling was conducted at 20 sites during summer 2015 and winter 2016 in Yazd. Concentrations of BTEX were analyzed using a gas chromatograph with a flame ionization detector (GC-FID). In addition, ozone formation potential (OFP) and the health risks of BTEX were calculated. Spatial mapping was accomplished using the Kriging method. The obtained concentrations of total BTEX ranged from 8 to 560 μg/m3. The highest average individual values belonged to toluene and xylene (38 ± 42 and 41 ± 45 μg/m3, respectively). Seasonal variation showed a downward trend from summer to winter. The peak BTEX emissions occurred in the evenings, due to rush hour traffic and meteorological factors. Spatial analysis showed that the maximum levels of BTEX occurred on high traffic roads or near fuel stations. Significant correlation coefficients between benzene and other BTEX compounds revealed that BTEX were emitted from main sources including gasoline vehicles and stations. The mean ratio of toluene/benzene (T/B) in summer (1.8) was more than winter (1.4). The seasonal changes in T/B ratio possibly were attributed to photochemistry, meteorology, and emission aspects. The OFP values were 720 ± 729 and 375 ± 319 μg/m3 in summer and winter, respectively. OFPs, ranked maximum to minimum, were as follows: xylene > toluene > ethylbenzene > benzene. Although the values of the non-cancer risk of BTEX were under permissible recommended level, a cancer risk still exists because of high values of airborne benzene.
显示更多 [+] 显示较少 [-]Lost in the North: The first record of Diretmichthys parini (Post and Quéro, 1981) in the northern North Sea 全文
2017
Cresson, Pierre | Rouquette, Manuel | Marco-miralles, Francoise | Dufour, Jean-louis | Causse, Romain | Bouchoucha, Marc | Mahe, Kelig
In June 2015, an individual of Diretmichthys parini (Post and Quero, 1981) was trawled at 530 m depth, in the North Sea off Norway and donated to research. This capture, the first for this species in the North Sea was the northernmost recorded so far, and provided an opportunity to document some aspects of the biology and ecology of this data-poor species. This individual was a female, 331 mm total length of 33 years old, with low mercury content in muscle and liver (~ 0.2 μg g− 1 wet mass). Stable isotope ratios (C and N) in muscle and liver were consistent with the planktonic diet expected for this species. The capture of this fish at the northern latitude known so far would be consistent with the extension of the home range and the latitudinal shift hypothesized for this species in the 1990′s.
显示更多 [+] 显示较少 [-]Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios 全文
2017
Cresson, Pierre | Travers-trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-andre | Giraldo, Carolina | Lefebvre, Sebastien | Ernande, Bruno
Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios 全文
2017
Cresson, Pierre | Travers-trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-andre | Giraldo, Carolina | Lefebvre, Sebastien | Ernande, Bruno
Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed variability demonstrated that using the theoretical CF may be inaccurate, when actual CF largely differs from the theoretical value. Dedicated measurement is the better approach when accuracy is required.
显示更多 [+] 显示较少 [-]Underestimation of chemical contamination in marine fish muscle tissue can be reduced by considering variable wet:dry weight ratios 全文
2017
Cresson, Pierre | Travers-Trolet, Morgane | Rouquette, Manuel | Timmerman, Charles-André | Giraldo, Carolina | Lefebvre, Sébastien | Ernande, Bruno
Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed variability demonstrated that using the theoretical CF may be inaccurate, when actual CF largely differs from the theoretical value. Dedicated measurement is the better approach when accuracy is required.
显示更多 [+] 显示较少 [-]Molecular phylogeny and toxicity of harmful benthic dinoflagellates Coolia (Ostreopsidaceae, Dinophyceae) in a sub-tropical marine ecosystem: The first record from Hong Kong 全文
2017
Leung, Priscilla T.Y. | Yan, Meng | Yiu, Sam K.F. | Lam, Veronica T.T. | Ip, Jack C.H. | Au, Maggie W.Y. | Chen, Chia-Yun | Wai, Tak-Cheung | Lam, Paul K.S.
Coolia are marine benthic dinoflagellates which are globally distributed and potentially toxic. This study provides the first investigation of species diversity and toxicity assessment of Coolia in Hong Kong waters. Fifty-one strains of four Coolia species, including C. malayensis, C. canariensis, C. tropicalis, and C. palmyrensis, were isolated from twelve sub-tidal habitats, and identified phylogenetically using 28S rDNA sequences. Exposure experiments (48-hour) demonstrated that the algal lysates extracted from the four Coolia species exhibited different toxic effects on the lethality and abnormality of two invertebrate larvae, i.e., brine shrimp Artemia franciscana and sea urchin Heliocidaris crassispina. Heliocidaris crassispina was more sensitive to the toxic effects of Coolia species than A. franciscana. Toxicity tests from both larvae revealed that C. malayensis was generally more toxic, and caused higher mortality rates when compared with the other three species. The emerging threat of harmful benthic dinoflagellates to marine environments and sensitive biota is discussed.
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