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Marine litter and public involvement in beach cleaning: Disentangling perception and awareness among adults and children, Bay of Biscay, Spain 全文
2019
Rayon-Viña, Fernando | Miralles, Laura | Fernandez-Rodríguez, Sara | Dopico, Eduardo | García Vázquez, Eva
Coastal litter abundance and its effects have increased for years. Waste reduction is the most effective countermeasure to fight against this problem. Littering attitudes may have an effect on people's involvement in coastal cleanups. In this study, coastal litter perception, awareness about its impact and likely sources were investigated in local population from south Bay of Biscay, Spain. People of different age groups and commitment levels regarding litter were interviewed and their answers compared with data from the area. Results showed differences in perception between volunteers and non-volunteers, but not between children and adults. Interaction effect of age was found for awareness. Volunteers and children tended to erroneously attribute the main litter origin to beachgoers, more than non-volunteers or adults. Our results suggest that encouraging local population to clean beaches would contribute to improve their perception of the problem and their attitudes toward taking action.
显示更多 [+] 显示较少 [-]Molecular methods for cost-efficient monitoring of HAB (harmful algal bloom) dinoflagellate resting cysts 全文
2019
Perini, F. | Bastianini, M. | Capellacci, S. | Pugliese, L. | DiPoi, E. | Cabrini, M. | Buratti, S. | Marini, M. | Penna, A.
Cyst abundance and identity are essential for understanding and predicting blooms, and for assessing the dispersal of toxic target dinoflagellate species by natural or human mediated ways, as with ballast waters. The aim of this study was to apply rapid, specific and sensitive qPCR assays to enumerate toxic dinoflagellate cysts in sediment samples collected from Adriatic harbours. The molecular standard curves of various target species allowed obtaining the rDNA copy number per cyst. The analytical sensitivity for specific standard curves was determined to be 2 or 10 rDNA copies per reaction. The abundance varied in the range of 1–747 dinoflagellate cysts g⁻¹ dry weight. The assays showed greater sensitivity as compared to counts by light microscopy. This qPCR method revealed a powerful tool for the quantification of cysts from toxic dinoflagellate resting stages in sediment samples from Adriatic ports.
显示更多 [+] 显示较少 [-]Zooplankton in Adriatic port environments: Indigenous communities and non-indigenous species 全文
2019
Vidjak, Olja | Bojanić, Natalia | de Olazabal, Alessandra | Benzi, Margherita | Brautović, Igor | Camatti, Elisa | Hure, Marijana | Lipej, Lovrenc | Lučić, Davor | Pansera, Marco | Pećarević, Marijana | Pestorić, Branka | Pigozzi, Silvia | Tirelli, Valentina
The zooplankton community was analyzed in ten Adriatic ports as part of the port biological baseline surveys carried out within the framework of the BALMAS project. We provide the first inventory of resident zooplankton taxa and five detected non-indigenous zooplankton species (NIS), and their spatial and seasonal distribution patterns. Copepoda and meroplankton larvae, particularly of Mollusca, dominated the zooplankton in all sampled ports. We recorded a total of 76 indigenous copepod species and five NIS, among which Parvocalanus crassirostris detected in Šibenik and Rijeka ports and Oithona davisae in Venice port, are new for the Adriatic. All detected NIS were widely distributed within the recipient ports. Co-occurrences of NIS were observed in the ports of Venice, Bari, Ancona and Trieste. The results are expected to contribute to the quality of practical monitoring of zooplankton NIS and facilitate the synchronization of efforts in creating NIS-related policies for the Adriatic sub-region.
显示更多 [+] 显示较少 [-]Holocene background concentrations and actual enrichment factors of metals in sediments from Ria Formosa, Portugal 全文
2019
Mendes Sousa, Carlos A. | Sousa, Carlos A.M. | Delgado, J. (Joaquín) | Szalaj, Dorota | Boski, Tomasz
Metal history in a natural system was described since the early Holocene by analysing the preserved subsurface sediment record and present-day surface sediments. Normalized geochemical data from six sediment cores (129 samples) was compared with 28 surface samples. Pre-anthropic sedimentary environments allowed the definition of local natural Background Values. Enrichment Factors were then used for elements discrimination in terms of natural and anthropogenic inputs to the system. While subsurface results displayed a similar behaviour in all cores, pointing to largely undisturbed system, surface sediments show significant contamination, with high enrichment factors for As, Cu, Pb, and Zn. Other metal pollutants have generally low enrichment values, suggesting natural conditions. Surface results were reproduced as metal enrichment maps which evidenced anthropogenic sources in specific locations. This work reveals the importance of combining subsurface and surface geochemical data with mapping techniques in order to better evaluate the environmental quality of a natural system.
显示更多 [+] 显示较少 [-]Assessing the source of oil deposited in the surface sediment of Mormugao Port, Goa - A case study of MV Qing incident 全文
2019
Suneel, V. | Saha, Mahua | Rathore, Chayanika | Sequeira, Jenica | Mohan, P.M Nikhil | Ray, Durbar | Veerasingam, S. | Rao, V Trinadha | Vethamony, P.
In June 2016, a cruise vessel was grounded in the Mormugao Port, resulting in unnoticed oil spill. The surface water and sediment samples were collected from the vicinity of the ship, and also an oil sample from the ship (OIL). These samples were subject to petroleum biomarker such as pentacyclic triterpenes (hopanes) and compound specific carbon isotopic (δ¹³C) analyses to assess the source of hydrocarbon pollution in the Mormugao Port. While no clear trend was observed in water samples, the bottom surface sediments did show an identical pattern of hopanes with the oil. The chemometric analyses of hopane Diagnostic Ratios (DRs) and δ¹³C ratios confirmed the ship oil as the source of oil pollution in sediments. Whereas the water is comparatively more dynamic than the sediment, the physical processes arising out of winds, waves, tides and currents might have dispersed the oil away from the grounded ship.
显示更多 [+] 显示较少 [-]Metal pollution affects both native and non-indigenous biofouling recruitment in a subtropical island system 全文
2019
Ramalhosa, Patrício | Gestoso, Ignacio | Duarte, Bernardo | Caçador, Isabel | Canning-Clode, João
Hull fouling has been a driving force behind the development of most modern marine antifouling coatings that mainly contain copper based biocides to inhibit growth of fouling organisms. Despite these efforts, several non-indigenous species continue to be transferred via hull-fouling worldwide. In this study we designed a disturbance gradient with three commercial antifouling paints applied to PVC settling plates with different concentrations of copper oxide and allowed colonization of fouling communities in four marinas located at the Madeira Archipelago (NE Atlantic). Overall, the antifouling treatments were effective in decreasing the diversity of fouling communities and spatial variability across marinas was observed. Increasing exposure to metal pollutants decreases both species cover and total diversity, independently of their native or NIS condition. However, evidences found suggest that long-term effects of copper based antifouling coatings can be modulated by metal-resistant species allowing a secondary substrate for the epibiosis of other species to establish.
显示更多 [+] 显示较少 [-]Differential impact of anthropogenic pressures on Caspian Sea ecoregions 全文
2019
Lattuada, Matteo | Albrecht, Christian | Wilke, Thomas
Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.
显示更多 [+] 显示较少 [-]Determinants of airborne benzene evaporating from fresh crude oils released into seawater 全文
2019
Gjesteland, Ingrid | Hollund, Bjørg Eli | Kirkeleit, Jorunn | Daling, Per S. | Sørheim, Kristin Rist | Bråtveit, Magne
Benzene, toluene, ethylbenzene, xylenes, naphthalene and n-hexane evaporating from a thin oil film was measured for 30 min in a small-scale test system at 2 and 13 °C and the impact of physicochemical properties on airborne benzene with time after bulk oil release was studied. Linear mixed-effects models for airborne benzene in three time periods; first 5, first 15 and last 15 min of sampling, indicated that benzene content in fresh oil, oil group (condensate/light crude oil) and pour point were significant determinants explaining 63–73% of the total variance in the outcome variables. Oils with a high pour point evaporated considerably slower than oils with a low pour point. The mean air concentration of total volatile organic compounds was significatly higher at 13 °C (735 ppm) compared to 2 °C (386 ppm) immediately after release of oil, but at both temperatures the concentration rapidly declined.
显示更多 [+] 显示较少 [-]An interlaboratory comparison exercise for the determination of microplastics in standard sample bottles 全文
2019
Isobe, Atsuhiko | Buenaventura, Nina T. | Chastain, Stephen | Chavanich, Suchana | Cózar, Andrés | DeLorenzo, Marie | Hagmann, Pascal | Hinata, Hirofumi | Kozlovskii, Nikolai | Lusher, Amy L. | Martí, Elisa | Michida, Yutaka | Mu, Jingli | Ohno, Motomichi | Potter, Gael | Ross, Peter S. | Sagawa, Nao | Shim, Won Joon | Song, Young Kyoung | Takada, Hideshige | Tokai, Tadashi | Torii, Takaaki | Uchida, Keiichi | Vassillenko, Katerina | Viyakarn, Voranop | Zhang, Weiwei
An interlaboratory comparison exercise was conducted to assess the consistency of microplastic quantification across several laboratories. The test samples were prepared by mixing one liter seawater free of plastics, microplastics made from polypropylene, high- and low-density polyethylene, and artificial particles in two plastic bottles, and analyzed concurrently in 12 experienced laboratories around the world. The minimum requirements to quantify microplastics were examined by comparing actual numbers of microplastics in these sample bottles with numbers measured in each laboratory. The uncertainty was due to pervasive errors derived from inaccuracies in measuring sizes and/or misidentification of microplastics, including both false recognition and overlooking. The size distribution of microplastics should be smoothed using a running mean with a length of >0.5 mm to reduce uncertainty to less than ±20%. The number of microplastics <1 mm was underestimated by 20% even when using the best practice for measuring microplastics in laboratories.
显示更多 [+] 显示较少 [-]Endocrine and reproductive endpoints of Notothenia rossii and N. coriiceps: A baseline study for ecotoxicological monitoring in Antarctic waters 全文
2019
Ferreira, María Florencia | Lo Nostro, Fabiana | Honji, Renato | Ansaldo, Martin | Genovese, Griselda
Pollution threats Antarctica and scientists blame xenobiotics and anthropic activities. Yet little is known about their effect on Antarctic ichthyofauna. Accordingly, we investigated the endocrine system of male fish Notothenia rossii and N. coriiceps (Perciformes, Nototheniidae) collected during Austral summer. For N. rossii, hormone levels of estradiol, testosterone, and 11-ketotestosterone were higher in fish collected during March than those of January; whereas for N. coriiceps estradiol and androgens levels were higher and lower in March, respectively. Histological analysis of the testes showed an unrestricted lobular type with no pathological alterations. However, detection of vitellogenin-like in plasma and skin mucus were seen in 75% of N. coriiceps males and 7% of N. rossii males. This is the first report of mucus vitellogenin-like detection as a non-invasive biomarker of endocrine disruption in notothenioid males and settles a baseline for future studies of reproductive biology and endocrine disruption in Antarctic fishes.
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