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Evaluation of macroalgae and amphipods as bioindicators of petroleum hydrocarbons input into the marine environment Texte intégral
2019
Lourenço, Rafael André | Magalhães, Caio Augusto | Taniguchi, Satie | Siqueira, Silvana Gomes Leite | Jacobucci, Giuliano Buzá | Leite, Fosca Pedini Pereira | Bícego, Márcia Caruso
The brown alga Sargassum furcatum and three families of amphipods (Ampithoidae, Caprellidae and Hyalidae) associated to that algae were evaluated as bioindicators of petroleum hydrocarbons input into the marine environment of São Sebastião Channel, in southeastern region of Brazil. The n-alkanes pattern were mainly associated with the natural composition of the macroalgae and amphipods, although some indicatives of petroleum hydrocarbons such as unresolved complex mixture and the no predominance of odd over even n-alkanes have been observed in some samples. Total PAHs ranged from 33.4 to 2010 ng g⁻¹ dry weight with the predominance of low molecular weight PAHs, mostly of naphthalene and alkyl-naphthalenes, which also suggested petroleum input. Even in low concentration, Sargassum furcatum and amphipods species studied seems to be good indicators of the introduction of petroleum hydrocarbons.
Afficher plus [+] Moins [-]Monitoring the antioxidant activities by extracting the polyphenolic contents of algae collected from the Bosphorus Texte intégral
2019
Aslan, Ertugrul | Aksu, Abdullah | Korkmaz, Nagihan Ersoy | Taskin, Omer S. | Caglar, Nuray Balkis
The identification and quantification of ascorbic acid, phenolic acids and flavonoids were carried out simultaneously with a rapid method of reverse-phase high-performance liquid chromatography (RP-HPLC). Total flavonoid contents were being determined by UV–Vis spectrophotometry, and total phenolic contents were determined by UV–Vis spectrophotometry using the Folin-Ciocalteu Reagent (FCR) method.In all of the individual contents and total phenolic content analysis, the best results were obtained with the methanol-water solvent system. The methanol-hexane solvent system was selected as the best for the extraction of total flavonoid contents. The reason for this difference is the flavonoids in the analyzed samples which were the lipophilic character. Examining the algae species, the highest contents were achieved from Ulva lactuca and Ceramium rubrum species. Depending on industrial activity and the population density, regional characteristics have been shown to be effective in the changes of these contents which show antioxidant properties.
Afficher plus [+] Moins [-]Mercury cycling and bioaccumulation in a changing coastal system: From water to aquatic organisms Texte intégral
2019
La Colla, Noelia S. | Botté, Sandra E. | Marcovecchio, Jorge E.
Mercury cycling and bioaccumulation in a changing coastal system: From water to aquatic organisms Texte intégral
2019
La Colla, Noelia S. | Botté, Sandra E. | Marcovecchio, Jorge E.
This study evaluated -for the first time- the occurrence and distribution of total Hg in abiotic (dissolved and particulate water fractions) and biotic (gills and muscle tissues of six commercial fish species) compartments within a South American coastal environment with anthropogenic pressure. This study dealt with environmental issues on developing countries which, as they are in continuous growth, face the highest rate of coastal transformation.Total Hg content was determined by acid digestion and measured using a cold vapor atomic absorption spectrophotometer. Results revealed that dissolved Hg exceeded the recommended levels for superficial saline waters in 67% of the cases. Hg concentrations varied among fish species and its tissues. The results suggested that metal burden in fishes achieved a mean maximum accumulation towards the muscle, with concentrations below the international maximum permitted values. The estimated daily intakes calculated suggest that people would not experience significant health risks through fish consumption.
Afficher plus [+] Moins [-]Mercury cycling and bioaccumulation in a changing coastal system: From water to aquatic organisms Texte intégral
2019
la Colla, Noelia Soledad | Botté, Sandra Elizabeth | Marcovecchio, Jorge Eduardo
This study evaluated -for the first time- the occurrence and distribution of total Hg in abiotic (dissolved and particulate water fractions) and biotic (gills and muscle tissues of six commercial fish species) compartments within a South American coastal environment with anthropogenic pressure. This study dealt with environmental issues on developing countries which, as they are in continuous growth, face the highest rate of coastal transformation. Total Hg content was determined by acid digestion and measured using a cold vapor atomic absorption spectrophotometer. Results revealed that dissolved Hg exceeded the recommended levels for superficial saline waters in 67% of the cases. Hg concentrations varied among fish species and its tissues. The results suggested that metal burden in fishes achieved a mean maximum accumulation towards the muscle, with concentrations below the international maximum permitted values. The estimated daily intakes calculated suggest that people would not experience significant health risks through fish consumption. | Fil: la Colla, Noelia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina | Fil: Botté, Sandra Elizabeth. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina | Fil: Marcovecchio, Jorge Eduardo. Universidad FASTA "Santo Tomas de Aquino"; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina
Afficher plus [+] Moins [-]Origins of sediment organic matter and their contributions at three contrasting wetlands in a coastal semi-enclosed ecosystem Texte intégral
2019
Zhao, Chunyu | Jiang, Zhijian | Wu, Yunchao | Liu, Songlin | Cui, Lijun | Zhang, Jingping | Huang, Xiaoping
The origins of sediment organic matter (SOM) and their contributions were studied in three contrasting wetlands (mudflat, estuarine and mangrove) of Daya Bay, South China Sea. Lower sediment δ13C but higher δ15N values were observed in coastal wetland than in offshore water of the bay. Greater terrigenous organic matter (TOM) contribution to SOM was observed in lower tidal area in mudflat and estuarine wetland. Higher concentrations of total organic carbon and total nitrogen in the three wetlands, as well as lower sediment δ13C, were found in the wet season. Extremely lower sediment δ15N with higher seawater ammonia were observed in estuarine wetland than in mudflat and mangrove, which was caused by the input of 15N-depleted ammonia from petrochemical industrial wastewater. Mangrove contributed substantially to SOM, with a larger contribution in mangrove area than in non-mangrove area. The mean contribution of TOM to SOM was lower in mangrove than in mudflat.
Afficher plus [+] Moins [-]Trace elements in microplastics in Cartagena: A hotspot for plastic pollution at the Caribbean Texte intégral
2019
Acosta-Coley, Isabel | Mendez-Cuadro, Dario | Rodriguez-Cavallo, Erika | Rosa, Jesús de la | Olivero-Verbel, Jesus
Microplastics are new pollutants considered a source of concern for the oceans worldwide. This research reports the concentrations of trace metals on microplastics collected on beaches from Cartagena, an industrialized city in the Caribbean. Mercury (Hg) was quantified using a Hg analyzer and forty-seven trace elements were assessed by ICP/MS. Most abundant microplastics in beaches were those with the lower degree of surface degradation features (SDF), categorized as white-new polyethylene pellets, followed by secondary microplastics (SM). Greater Hg levels were found in SM, white-degraded (WDP) and black pellets. Trace elements concentrations were linked to the degree of SDF registered in examined pellets, with larger concentrations in WDP. Compared to white-new pellets, Ba, Cr, Rb, Sr, Ce, Zr, Ni, Pb were the most accumulated elements in WDP, as their surface enhance the sorption processes. Microplastic pollution represents a toxicological hazard because its ability to accumulate and transport toxic elements.
Afficher plus [+] Moins [-]Impact of environmental variables on fouling bryozoan species in the Eastern Aegean Sea Texte intégral
2019
Kocak, Ferah | Kucuksezgin, Filiz | Bakal, Ilkin
Bryozoans are the major component of marine macro-fouling communities. In the study, the relations between bryozoan species and environmental variables were investigated at seven stations along the Aegean coast in August and December 2015. Constant bryozoan species in both sampling periods were Bugula neritina, Amathia verticillata, Shizoporella errata, Cryptosula pallasiana and Celleporaria brunnea. Their relationship with physico-chemical variables (Temperature, salinity, pH, dissolved oxygen, ammonium, nitrite and nitrate nitrogen, orthophosphate phosphorous, total phosphate, chlorophyll-a) were analysed by means of logistic regression analysis. The result showed that temperature with B. neritina; NH4-N, oPO4-P and TPO4-P with A verticillata; dissolved oxygen concentrations with S. errata and C. brunnea were positively related (p < 0.05).
Afficher plus [+] Moins [-]Plastics occurrence in the gastrointestinal tract of Zeus faber and Lepidopus caudatus from the Tyrrhenian Sea Texte intégral
2019
Bottari, Teresa | Nunziacarla, Spanò | Savoca, Serena | Mancuso, Monique | Capillo, Gioele | GiuseppePanarello, Giuseppe | MartinaBonsignore, Martina | Crupi, Rosalia | Sanfilippo, Marilena | D'Urso, Luisa | Compagnini, Giuseppe | Neri, Fortunato | Romeo, Teresa | Luna, Gian Marco | Spanò, Nunziacarla | Fazio, Enza
The present study investigates the occurrence of plastic pollution in two commercially important marine teleosts (Zeus faber and Lepidopus caudatus) from the northern coasts of Sicily (Tyrrhenian Sea). Plastics occurrence in the gastrointestinal tract was higher in Lepidopus caudatus (78.1%) than Zeus faber (51.4%). Debris characterization, carried out by micro-Raman spectroscopy, allowed identified the main types of found polymers as: polypropylene (PP), polyamide (PA), nylon and, to a lesser extent, polyethylene (PE). Of the two fish species studied, the silver scabbardfish appeared to be the more vulnerable to plastic ingestion. Our study represents a starting point that may pave the way for future investigation of the fate, accumulation and transfer of plastic debris to upper trophic levels, to verify their potential toxicity and to better understand strategies to mitigate this phenomenon.
Afficher plus [+] Moins [-]Analysis of anatomical changes and cadmium distribution in Aegiceras corniculatum (L.) Blanco roots under cadmium stress Texte intégral
2019
Li, Jian | Yu, Junyi | Du, Daolin | Liu, Jingchun | Lu, Haoliang | Yan, Chongling
Heavy metal stress changes the morphological and anatomical structure of plant organs. In this study, we determined the anatomical changes and Cd distribution in the roots of Aegiceras corniculatum (L.) Blanco (Black mangrove) under Cd stress. The results showed that Cd levels in A. corniculatum root tissues decreased in the following order: endodermis > pith > xylem > epidermis and exodermis > phloem > cortex. The endodermis secondary casparian strip replaces exodermis casparian strip and plays a role in the “retardation mechanism”, which sort of compensates for the missing exodermis retardation effect. The xylem and pith both show high affinity for Cd and contain enriched Cd. This creates a low-Cd environment for phloem and protects the nutrient transport function of the vasculature against Cd toxicity. The present study provides new evidences suggesting that Cd regional enrichment and anatomical structure changes are an adaptive strategy of mangrove plants to HM tolerance.
Afficher plus [+] Moins [-]Taking advantage of seagrass recovery potential to develop novel and effective meadow rehabilitation methods Texte intégral
2019
Alagna, Adriana | D'Anna, Giovanni | Musco, Luigi | Vega Fernández, Tomás | Gresta, Martina | Pierozzi, Natalia | Badalamenti, Fabio
Seagrasses are among the most threatened biomes worldwide. Until now, seagrass rehabilitation success has reached about 38% overall and more effective approaches to restoration are urgently needed. Here we report a novel method to rehabilitate Posidonia oceanica meadows based on observation of the species' natural recovery after disturbance. Posidonia oceanica rhizomes were transplanted on gabions filled with rocks of selected sizes in order to build a firm substrate with topographic complexity in the relevant scale range to propagules. Five techniques were tested, each involving a different anchoring device. The “slot” technique, which uses a wire-net pocket to retain the cuttings, was the most successful, with survival exceeding 85% after thirty months. Branching allowed final shoot survival to reach 422% of initial planting density. This study shows how an in-depth knowledge of species life history processes provides a suitable foundation for developing effective restoration methods that benefit from species recovery ability.
Afficher plus [+] Moins [-]Incubation in light versus dark affects the vitality of UV-irradiated Tetraselmis suecica differently: A flow cytometric study Texte intégral
2019
Olsen, Ranveig O. | Lindivat, Mathilde | Larsen, Aud | Thuestad, Gunnar | Hoell, Ingunn Alne
In this study, we used flow cytometry to examine how incubation in dark versus light affects the vitality and viability of UV-irradiated Tetraselmis suecica. High UV doses (300 and 400 mJ/cm²) affected the esterase activity, membrane permeability, and chlorophyll content more when the subsequent incubation took place in light. For non- or low UV dose (100 and 200 mJ/cm²)-treated cells, incubation in light resulted in cell regrowth as compared to incubation in dark. Damaged cells (enzymatically active but with permeable membranes) did not recover when incubated under light or dark conditions.Exposure to light reduces the evaluation time of any given ballast water treatment, as viable cells will be detected at an earlier stage and the vitality is more affected. When evaluating the performance of UV-based ballast water treatment systems (BWTS), these results can be useful for type approval using T. suecica as a test organism in the test regime.
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