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Effects of oil and oil burn residues on seabird feathers Texto completo
2016
Fritt-Rasmussen, Janne | Linnebjerg, Jannie Fries | Sørensen, Martin X. | Brogaard, Nicholas L. | Rigét, Frank F. | Kristensen, Paneeraq | Jomaas, Grunde | Boertmann, David M. | Wegeberg, Susse | Gustavson, Kim
It is well known, that in case of oil spill, seabirds are among the groups of animals most vulnerable. Even small amounts of oil can have lethal effects by destroying the waterproofing of their plumage, leading to loss of insulation and buoyancy. In the Arctic these impacts are intensified. To protect seabirds, a rapid removal of oil is crucial and in situ burning could be an efficient method. In the present work exposure effects of oil and burn residue in different doses was studied on seabird feathers from legally hunted Common eider (Somateria mollissima) by examining changes in total weight of the feather and damages on the microstructure (Amalgamation Index) of the feathers before and after exposure. The results of the experiments indicate that burn residues from in situ burning of an oil spill have similar or larger fouling and damaging effects on seabird feathers, as compared to fresh oil.
Mostrar más [+] Menos [-]Distribution and abundance of surface water microlitter in the Baltic Sea: A comparison of two sampling methods Texto completo
2016
Setälä, Outi | Magnusson, Kerstin | Lehtiniemi, Maiju | Norén, Fredrik
Two methods for marine microlitter sampling were compared in the Gulf of Finland, northern Baltic Sea: manta trawl (333μm) and a submersible pump (300 or 100μm). Concentrations of microlitter (microplastics, combustion particles, non-synthetic fibres) in the samples collected with both methods and filter sizes remained <10particlesm−3. The pump with 100μm filter gave higher microlitter concentrations compared to manta trawl or pump with 300μm filter. Manta sampling covers larger areas, but is potentially subjected to contamination during sample processing and does not give precise volumetric values. Using a submerged pump allows method controls, use of different filter sizes and gives exact volumetric measures. Both devices need relatively calm weather for operation. The choice of the method in general depends on the aim of the study. For monitoring environmentally relevant size fractions of microlitter the use of 100μm or smaller mesh size is recommended for the Baltic Sea.
Mostrar más [+] Menos [-]Facilitating political decisions using species distribution models to assess restoration measures in heavily modified estuaries Texto completo
2016
Heuner, Maike | Weber, Arnd | Schröder, Uwe | Kleinschmit, Birgit | Schröder, Boris
The European Water Framework Directive requires a good ecological potential for heavily modified water bodies. This standard has not been reached for most large estuaries by 2015. Management plans for estuaries fall short in linking implementations between restoration measures and underlying spatial analyses. The distribution of emergent macrophytes – as an indicator of habitat quality – is here used to assess the ecological potential. Emergent macrophytes are capable of settling on gentle tidal flats where hydrodynamic stress is comparatively low. Analyzing their habitats based on spatial data, we set up species distribution models with ‘elevation relative to mean high water’, ‘mean bank slope’, and ‘length of bottom friction’ from shallow water up to the vegetation belt as key predictors representing hydrodynamic stress. Effects of restoration scenarios on habitats were assessed applying these models. Our findings endorse species distribution models as crucial spatial planning tools for implementing restoration measures in modified estuaries.
Mostrar más [+] Menos [-]Pharmaceutically active compounds and endocrine disrupting chemicals in water, sediments and mollusks in mangrove ecosystems from Singapore Texto completo
2016
Bayen, Stéphane | Estrada, Elvagris Segovia | Juhel, Guillaume | Kit, Lee Wei | Kelly, Barry C.
This study investigated the occurrence of bisphenol A (BPA), atrazine and selected pharmaceutically active compounds (PhACs) in mangrove habitats in Singapore in 2012–2013, using multiple tools (sediment sampling, POCIS and filter feeder molluscs). Using POCIS, the same suite of contaminants (atrazine, BPA and eleven PhACs) was detected in mangrove waters in 28-days deployments in both 2012 and 2013. POCIS concentrations ranged from pg/L to μg/L. Caffeine, BPA, carbamazepine, E1, triclosan, sulfamerazine, sulfamethazine, and lincomycin were also detected in mangrove sediments from the low pg/g dw (e.g. carbamazepine) to ng/g dw (e.g. BPA). The detection of caffeine, carbamazepine, BPA, sulfamethoxazole or lincomycin in bivalve tissues also showed that these chemicals are bioavailable in the mangrove habitat. Since there are some indications that some pharmaceutically active substances may be biologically active in the low ppb range in marine species, further assessment should be completed based on ecotoxicological data specific to mangrove species.
Mostrar más [+] Menos [-]Prevalence of microplastics in the marine waters of Qatar Texto completo
2016
Castillo, Azenith B. | Al-Maslamani, Ibrahim | Obbard, Jeffrey Philip
Prevalence of microplastics in the marine waters of Qatar Texto completo
2016
Castillo, Azenith B. | Al-Maslamani, Ibrahim | Obbard, Jeffrey Philip
Microplastics are firmly recognized as a ubiquitous and growing threat to marine biota and their associated marine habitats worldwide. The evidence of the prevalence of microplastics was documented for the first time in the marine waters of Qatar's Exclusive Economic Zone (EEZ). An optimized and validated protocol was developed for the extraction of microplastics from plankton-rich seawater samples without loss of microplastic debris present and characterized using Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy. In total 30 microplastic polymers have been identified with an average concentration of 0.71particlesm−3 (range 0–3particlesm−3). Polypropylene, low density polyethylene, polyethylene, polystyrene, polyamide, polymethyl methacrylate, cellophane, and acrylonitrile butadiene styrene polymers were characterized with majority of the microplastics either granular shape, sizes ranging from 125μm to 1.82mm or fibrous with sizes from 150μm to 15.98mm. The microplastics are evident in areas where nearby anthropogenic activities, including oil-rig installations and shipping operations are present.
Mostrar más [+] Menos [-]Prevalence of microplastics in the marine waters of Qatar Texto completo
2016
Castillo, Azenith B. | Al-Maslamani, Ibrahim | Obbard, Jeffrey Philip
The issue of plastic pollution in the marine environment is of increasing global concern. As plastics typically have an intrinsic durability, water insolubility and slow degradation rates, debris has now become both ubiquitous and persistent in the marine environment. Overtime, plastic ultimately result in the generation of microplastics via photolytic, thermal and biological degradation processes. Although the potential threat of microplastics on marine ecosystems is well recognized, there is no baseline data available for the Arabian Gulf. The Environmental Science Center of Qatar University has now documented the first evidence for the prevalence of microplastics within the Arabian Gulf, specifically in the marine waters of Qatar Exclusive Economic Zone (EEZ). Qatar has an arid climate and is situated midway along the western coast of the semi-enclosed Arabian Gulf. Qatar's coastline is particularly susceptible to marine debris due to the county's rapid urbanization and economic development. Surface seawater samples were collected from 12 stations during May 2015 research cruise of the RV Janan. An optimized and validated protocol was developed for the extraction of microplastics from plankton-rich samples without loss of microplastics present. Plankton present in seawater samples may readily mask the identification of microplastics and lead to an underestimation of the quantity of microplastics present. The protocol involved sample digestion using solutions of 1M NaOH, 10M NaOH, and 16M HNO3 in conjunction at different temperatures. Twenty mL of each solution was spiked with known quantities of reference polymer pellets, of varying diameters (63 μm to 4.70 mm) and used to digest the plankton biomass. The use of 1M NaOH proved to be a more efficient digestion treatment than 10M NaOH and 16M HNO3 solutions. Although 10M NaOH, and 16M HNO3 have been proven effective to mineralize plankton biomass, these solutions also resulted in some structural damage and discoloration of reference polymers with a low pH tolerance: polyvinyl alcohol, polyvinyl chloride, polystyrene, polyethylene, and nylon. After extraction, the microplastics were characterized using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. In total 30 microplastics were isolated from the mineralized samples, with an average concentration of 0.71 particles m− 3 (range 0–3 particles m− 3). Nine out of 30 were identified as polypropylene, with the majority either granular, sizes ranging from 125 μm to 1.82 mm, or fibrous, sizes from 150 μm to 15.98 mm. Microplastics were more prevalent in areas where nearby anthropogenic activities, including oil-rig installations and shipping operations, are present. | qscience
Mostrar más [+] Menos [-]Application of empirical model to predict background metal concentration in mixed carbonate-alumosilicate sediment (Adriatic Sea, Croatia) Texto completo
2016
Felja, Igor | Romić, Marija | Romić, Davor | Bakić, Helena | Pikelj, Kristina | Juračić, Mladen
A 96m long sediment core (S10-33) from the Mali Ston Channel (Adriatic Sea) showed large natural variation in carbonate share (between 1% and 95%) and concentration of elements. These variations indicate rather significant changes in fine-grained sediment that was deposited in this area during Younger Pleistocene and Holocene. Unaffected by anthropogenic influence, sediment in the core was used to determine background concentration of trace elements in sediment with various carbonate content. Here we propose a method of the normalization of trace elements to carbonate share, in order to assess natural/background concentration of metals in sediments consisting of carbonates and alumosilicates in various proportions. Six characteristic metals (Co, Cr, Cu, Ni, Pb, and Zn) that were normalized to carbonate share showed very good correlation, with much higher background concentrations in alumosilicate than in carbonate end member. Simple formulas were proposed to easily determine background concentration of these elements, in coastal and shelf depositional environments with mixed carbonate-alumosilicate sediments.
Mostrar más [+] Menos [-]Biodegradation of marine crude oil pollution using a salt-tolerant bacterial consortium isolated from Bohai Bay, China Texto completo
2016
Li, xinfei | Zhao, Lin | Adam, Mohamed
This study aims at constructing an efficient bacterial consortium to biodegrade crude oil spilled in China's Bohai Sea. In this study, TCOB-1 (Ochrobactrum), TCOB-2 (Brevundimonas), TCOB-3 (Brevundimonas), TCOB-4 (Bacillus) and TCOB-5 (Castellaniella) were isolated from Bohai Bay. Through the analysis of hydrocarbon biodegradation, TCOB-4 was found to biodegrade more middle-chain n-alkanes (from C17 to C23) and long-chain n-alkanes (C31–C36). TCOB-5 capable to degrade more n-alkanes including C24–C30 and aromatics. On the basis of complementary advantages, TCOB-4 and TCOB-5 were chosen to construct a consortium which was capable of degrading about 51.87% of crude oil (2% w/v) after 1week of incubation in saline MSM (3% NaCl). It is more efficient compared with single strain. In order to biodegrade crude oil, the construction of bacterial consortia is essential and the principle of complementary advantages could reduce competition between microbes.
Mostrar más [+] Menos [-]Distribution of trace metals in surface seawater and zooplankton of the Bay of Bengal, off Rushikulya estuary, East Coast of India Texto completo
2016
Srichandan, Suchismita | Panigrahy, R.C. | Baliarsingh, S.K. | Rao B., Srinivasa | Pati, Premalata | Sahu, Biraja K. | Sahu, K.C.
Concentrations of trace metals such as iron (Fe), copper (Cu), zinc (Zn), cobalt (Co), nickel (Ni), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), vanadium (V), and selenium (Se) were determined in seawater and zooplankton from the surface waters off Rushikulya estuary, north-western Bay of Bengal. During the study period, the concentration of trace metals in seawater and zooplankton showed significant spatio-temporal variation. Cu and Co levels in seawater mostly remained non-detectable. Other elements were found at higher concentrations and exhibited marked variations. The rank order distribution of trace metals in terms of their average concentration in seawater was observed as Fe>Ni>Mn>Pb>As>Zn>Cr>V>Se>Cd while in zooplankton it was Fe>Mn>Cd>As>Pb>Ni>Cr>Zn>V>Se. The bioaccumulation factor (BAF) of Fe was highest followed by Zn and the lowest value was observed with Ni. Results of correlation analysis discerned positive affinity and good relationship among the majority of the trace metals, both in seawater and zooplankton suggesting their strong affinity and coexistence.
Mostrar más [+] Menos [-]Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texto completo
2016
Miralles, Laura | Dopico, Eduardo | Devlo-Delva, Floriaan | García Vázquez, Eva
Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texto completo
2016
Miralles, Laura | Dopico, Eduardo | Devlo-Delva, Floriaan | García Vázquez, Eva
Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions.
Mostrar más [+] Menos [-]Controlling populations of invasive pygmy mussel (Xenostrobus securis) through citizen science and environmental DNA Texto completo
2016
Miralles López, Laura | Dopico Rodríguez, Eduardo Vicente | Devlo-Delva, F. | García Vázquez, Eva
This study has been supported by the Port of Aviles Authorities (contract FUO-EM-261-15), and the Spanish Ministry of Economy and Competitiveness Grant CGL-2013-42415-R. This is a contribution from the Asturias Marine Observatory. FDD is grateful to EMBC (Marine Biodiversity and Conservation Master).
Mostrar más [+] Menos [-]Spatiotemporal characteristics and health effects of air pollutants in Shenzhen Texto completo
2016
Wu, Yongsheng | Zhang, Fengying | Shi, Yu | Pilot, Eva | Lin, Lanyu | Fu, Yingbin | Krafft, Thomas | Wang, Wuyi
In this study, spatiotemporal patterns and health effects in all-cause mortality of air pollutants (CO, NO2, and SO2) during 2013 in Shenzhen were investigated. Spatiotemporal characteristics of air quality index (AQI) and air quality are also addressed. The results show that daily averages were 10.9 μg/m3 for SO2, 39.6 μg/m3 for NO2, and 1.2 mg/m3 for CO. Daily AQI ranged from 24 to 179. There were approximately 39 days of air pollution in Shenzhen. NO2 was the third major air pollutant. Monthly/hourly average AQI and concentrations of NO2 and SO2 in the city center area were higher than in tourist areas. Annual AQI and NO2 concentration were higher in western parts of Shenzhen, whereas SO2 was higher in eastern portions. The lowest CO concentration was in the Luohu District. Relative risks of mortality number increased with SO2/NO2 levels. When SO2/NO2 concentration changed, female individuals were more sensitive than male individuals, and people aged older than 65 years were more affected than younger people.
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