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Plastic debris and microplastics along the beaches of the Strait of Hormuz, Persian Gulf Texte intégral
2017
Naji, Abolfazl | Esmaili, Zinat | Khan, Farhan R
Currently little is known about the prevalence of plastics and microplastics (MPs) in the Persian Gulf. Five sampling stations were selected along the Strait of Hormuz (Iran) that exhibited different levels of industrialization and urbanization, and included a marine protected area. Debris was observed and sediments were collected for MPs extraction via fluidization/floatation methodology. The order of MP abundance (par/kg) generally reflected the level of anthropogenic activity: Bostanu (1258±291)>Gorsozan (122±23)>Khor-e-Yekshabeh (26±6)>Suru (14±4)>Khor-e-Azini (2±1). Across all sites fibers dominated (83%, 11% film, 6% fragments). FT-IR analysis showed polyethylene (PE), nylon, and PET (polyethylene terephthalate) were the commonly recovered polymers. Likely sources include beach debris, discarded fishing gear, and urban and industrial outflows that contain fibers from clothes. This study provides a ‘snapshot’ of MP pollution and longitudinal studies are required to fully understand plastic contamination in the region.
Afficher plus [+] Moins [-]Spatial and temporal variation of macro-, meso- and microplastic abundance on a remote coral island of the Maldives, Indian Ocean Texte intégral
2017
Imhof, Hannes K. | Sigl, Robert | Brauer, Emilia | Feyl, Sabine | Giesemann, Philipp | Klink, Saskia | Leupolz, Kathrin | Löder, Martin G.J. | Löschel, Lena A. | Missun, Jan | Muszynski, Sarah | Ramsperger, Anja F.R.M. | Schrank, Isabella | Speck, Susan | Steibl, Sebastian | Trotter, Benjamin | Winter, Isabel | Laforsch, Christian
Plastic debris is ubiquitous in the marine environment and the world's shores represent a major sink. However, knowledge about plastic abundance in remote areas is scarce. Therefore, plastic abundance was investigated on a small island of the Maldives. Plastic debris (>1mm) was sampled once in natural long-term accumulation zones at the north shore and at the high tide drift line of the south shore on seven consecutive days to quantify daily plastic accumulation. Reliable identification of plastic debris was ensured by FTIR spectroscopy. Despite the remoteness of the island a considerable amount of plastic debris was present. At both sites a high variability in plastic abundance on a spatial and temporal scale was observed, which may be best explained by environmental factors. In addition, our results show that snapshot sampling may deliver biased results and indicate that future monitoring programs should consider spatial and temporal variation of plastic deposition.
Afficher plus [+] Moins [-]The uptake of macroplastic & microplastic by demersal & pelagic fish in the Northeast Atlantic around Scotland Texte intégral
2017
This study reports plastic ingestion in various fish found from coastal and offshore sites in Scottish marine waters. Coastal samples consisted of three demersal flatfish species (n=128) collected from the East and West coasts of Scotland. Offshore samples consisted of 5 pelagic species and 4 demersal species (n=84) collected from the Northeast Atlantic. From the coastal fish sampled, 47.7% of the gastrointestinal tracts contained macroplastic and microplastic. Of the 84 pelagic and demersal offshore fish, only 2 (2.4%) individuals from different species had ingested plastic identified as a clear polystyrene fibre and a black polyamide fibre. The average number of plastic items found per fish from all locations that had ingested plastic was 1.8 (±1.7) with polyamide (65.3%), polyethylene terephthalate (14.4%) and acrylic (14.4%) being the three most commonly found plastics. This study adds to the existing data on macroplastic and microplastic ingestion in fish species.
Afficher plus [+] Moins [-]Potentially toxic filamentous fungi associated to the economically important Nodipecten nodosus (Linnaeus, 1758) scallop farmed in southeastern Rio de Janeiro, Brazil Texte intégral
2017
Numerous countries have been confronted with infectious diseases in mariculture activities, including fungi infections, although reports in scallops are scarce. Thus, this study aimed to investigate the occurrence of filamentous fungi in Nodipecten nodosus specimens from three marine farms in Southeastern Brazil. Eight fungi genera were observed in the branchial arches, intestine and muscle tissue of the scallop specimens. These include potentially toxin-producing species, such as Aspergillus, Penicillium and Fusarium. Their presence may lead to potential public health concerns, since all sampling sites showed the presence of fungi in all scallop organs, with special concern regarding edible muscle tissue. A significant number of species was observed at one of the study areas, which could indicate a previously unknown source of contamination, since increases in fungi species richness in polluted coastal waters have been reported. This is also, to the best of our knowledge, the first report of Pestalotiopsis in shellfish.
Afficher plus [+] Moins [-]Bioremediation using Gracilaria lemaneiformis to manage the nitrogen and phosphorous balance in an integrated multi-trophic aquaculture system in Yantian Bay, China Texte intégral
2017
Wei, Zhangliang | You, Jiaguo | Wu, Hailong | Yang, Fangfang | Long, Lijuan | Liu, Qiao | Huo, Yuanzi | He, Peimin
To reduce negative environmental impacts from human aquaculture activities, the red alga Gracilaria lemaneiformis was co-cultured with the fish Pseudosciaena crocea in an integrated multi-trophic aquaculture (IMTA) system for 35d in Yantian Bay. The eutrophication index value decreased from 14.5 to 8.4 after seaweeds were co-cultured in cage farming areas, which indicated that the eutrophic water column in Yantian Bay could be mediated by IMTA. Total DIN and DIP of the tidal input and output were 9.23kg, 0.19kg and 11.08kg, and 0.27kg, respectively. Total 5.24kg of dissolved N and 0.81kg of dissolved P were released from IMTA system. These results indicate that G. lemaneiformis co-cultured in IMTA system could not completely remove all excess nutrients. In theory, at least 324.48kg of seaweed seedlings would be required to balance excess nutrients generated from fish cages.
Afficher plus [+] Moins [-]Long term effects of urbanisation and anthropic alterations on river fish assemblages. | Réponse des peuplements de poissons à l'urbanisation et aux altérations anthropiques à long terme des cours d’eau. Texte intégral
2017
Tales, Evelyne | Belliard, Jérôme | Beslagic, Sarah | Stefani, Fabrizio | Tartari, Gianni | Wolter, Christian | Hydrosystèmes et Bioprocédés (UR HBAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Consiglio Nazionale delle Ricerche [Bologna] (CNR) | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB) ; Leibniz Association | Lestel, L. | Carré, C.
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE | Dans cette étude, nous avons comparé l'évolution de trois grandes villes,
Afficher plus [+] Moins [-]Influence of crude oil exposure on cardiac function and thermal tolerance of juvenile rainbow trout and European sea bass Texte intégral
2017
Anttila, Katja | Mauduit, Florian | Le Floch, Stephane | Claireaux, Guy | Nikinmaa, Mikko
Influence of crude oil exposure on cardiac function and thermal tolerance of juvenile rainbow trout and European sea bass Texte intégral
2017
Anttila, Katja | Mauduit, Florian | Le Floch, Stephane | Claireaux, Guy | Nikinmaa, Mikko
Oil spills pose a threat to aquatic organisms. However, the physiological effects of crude oil on cardiac function and on thermal tolerance of juvenile fish are still poorly understood. Consequently, in this paper, we will present results of two separate experiments where we exposed juvenile rainbow trout and European sea bass to crude oil and made cardiac thermal tolerances and maximum heart rate (fHmax) measurements after 1 week (rainbow trout) and 6-month recovery (sea bass). In both species, the fHmax was lower in crude oil-exposed fish than in the control ones at temperatures below the optimum but this difference disappeared at higher temperatures. More importantly, the oil-exposed fish had significantly higher Arrhenius break point temperature for fHmax, which gave an estimate for optimum temperature, than the control fish in both species even though the exposure conditions and recovery times differed between species. The results indicated that exposure of juvenile fish to crude oil did not have a significant negative impact upon their cardiac performance in high temperatures and upper thermal tolerance increased when the fish were tested 1 week or 6 months after the exposure. Our findings suggest that the cardiac function and thermal tolerance of juvenile fish are relatively resistant to a crude oil exposure.
Afficher plus [+] Moins [-]Influence of crude oil exposure on cardiac function and thermal tolerance of juvenile rainbow trout and European sea bass Texte intégral
2017
Anttila, Katja | Mauduit, Florian | Le Floch, Stéphane | Claireaux, Guy | Nikinmaa, Mikko
Oil spills pose a threat to aquatic organisms. However, the physiological effects of crude oil on cardiac function and on thermal tolerance of juvenile fish are still poorly understood. Consequently, in this paper, we will present results of two separate experiments where we exposed juvenile rainbow trout and European sea bass to crude oil and made cardiac thermal tolerances and maximum heart rate (f Hₘₐₓ) measurements after 1 week (rainbow trout) and 6-month recovery (sea bass). In both species, the f Hₘₐₓ was lower in crude oil-exposed fish than in the control ones at temperatures below the optimum but this difference disappeared at higher temperatures. More importantly, the oil-exposed fish had significantly higher Arrhenius break point temperature for f Hₘₐₓ, which gave an estimate for optimum temperature, than the control fish in both species even though the exposure conditions and recovery times differed between species. The results indicated that exposure of juvenile fish to crude oil did not have a significant negative impact upon their cardiac performance in high temperatures and upper thermal tolerance increased when the fish were tested 1 week or 6 months after the exposure. Our findings suggest that the cardiac function and thermal tolerance of juvenile fish are relatively resistant to a crude oil exposure.
Afficher plus [+] Moins [-]Investigation of aromatic hydrocarbon inclusion into cyclodextrins by Raman spectroscopy and thermal analysis Texte intégral
2017
Tijunelyte, Inga | Dupont, Nathalie | Milosevic, Irena | Barbey, Carole | Rinnert, Emmanuel | Lidgi-guigui, Nathalie | Guenin, Erwann | De La Chapelle, Marc Lamy
Among various cavitand molecules, cyclodextrins are extensively studied due to their ability to form host-guest complexes with small hydrophobic molecules. Aiming to explore cyclodextrin implementation on the scopes related to the environmental pollution monitoring or remediation, extensive studies for understanding the cyclodextrin-based host-guest complex formation with selected targeted substances are conducted. In this context, two polycyclic aromatic hydrocarbons, naphthalene and fluoranthene as well as toluene as a member of volatile organic compounds, were studied regarding their ability to encapsulate into cyclodextrin cavities. Synthesised complexes were examined by thermogravimetric analysis combined with Raman spectroscopy. The obtained results demonstrated that the size between targeted molecules and the cyclodextrin cavities strongly correlates with its ability to engage in complexation. Thus, this latter parameter plays an important role in the inclusion complex formation as well as in the strength of the interaction between the molecules.
Afficher plus [+] Moins [-]Near-surface distribution of pollutants in coastal waters as assessed by novel polyethylene passive samplers Texte intégral
2017
Aminot, Yann | Belles, Angel | Alary, Claire | Readman, James W.
We report a novel and inexpensive method to provide high resolution vertical measurements of temporally integrated organic contaminants in surface and sub-surface waters in polluted coastal environments. It employs a strip of polyethylene deployed as a passive sampler. Verifications are confirmed via conventional spot sample analyses and against Performance Reference Compound (PRC) calibration methods. Analytes targeted include 16 Polycyclic Aromatic Hydrocarbons, 15 personal care products, 8 organophosphorus flame retardants, 4 antifouling 'booster' biocides and 15 n-alkanes. Whilst all contaminants typically revealed homogeneous concentrations from 10 cm to 3 m depth in the selected harbour (<30% variations), many increased sharply at the air-sea interface. The passive sampler was shown to afford better resolution than could be achieved using conventional analytical techniques at the surface microlayer (SML). Whilst hydrophobicity appeared to be a key factor for the enrichment of many determinants, less correlation was found for the emerging contaminants.
Afficher plus [+] Moins [-]Degradation of N-Nitrosodimethylamine by UV-Based Advanced Oxidation Processes for Potable Reuse: a Short Review Texte intégral
2017
Fujioka, Takahiro | Masaki, Shunya | Kodamatani, Hitoshi | Ikehata, Keisuke
The ultraviolet (UV)-based advanced oxidation process (AOP) is a powerful technology commonly utilised in recent potable water reuse (PR) schemes. The AOP involves the generation of highly reactive free radicals (e.g. hydroxyl, HO•) and is primarily applied for the removal of two target trace organic chemicals—N-nitrosodimethylamine (NDMA) and 1,4-dioxane — in the PR schemes. Both of these organics are not well removed by the reverse osmosis (RO) process. NDMA is a probable carcinogen and is often present in reclaimed water at concentrations higher than the guidelines established for PR. This review aimed to provide an understanding of the current UV-based advanced oxidation technologies for NDMA removal in PR, their limitations and the future of advanced technologies for their removal. NDMA is readily photolysed by direct UV irradiation, while an AOP such as UV/H₂O₂ process is necessary for the destruction of 1,4-dioxane. Unfortunately, the generation of hydroxyl radicals through UV photolysis of H₂O₂ is largely inefficient with conversion on the order of 20% under normal plant operations and the addition of H₂O₂ (e.g. 3 mg/L) provides only a negligible improvement in NDMA destruction. However, AOP can also be achieved without continuous chemical addition through the application of UV irradiation to heterogeneous photocatalysts (e.g. TiO₂). The UV/TiO₂ process generates hydroxyl radicals and singlet oxygen molecules, both of which degrade NDMA into by-products (e.g. methylamine or dimethylamine). Recent studies revealed that modification of the surface morphology of TiO₂ can not only enhance NDMA destruction but also alter the composition of the degradation by-products.
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