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Barriers and benefits to desired behaviors for single use plastic items in northeast Ohio's Lake Erie basin Полный текст
2018
Bartolotta, Jill F. | Hardy, Scott D.
Given the growing saliency of plastic marine debris, and the impact of plastics on beaches and aquatic environments in the Laurentian Great Lakes, applied research is needed to support municipal and nongovernmental campaigns to prevent debris from reaching the water's edge. This study addresses this need by examining the barriers and benefits to positive behavior for two plastic debris items in northeast Ohio's Lake Erie basin: plastic bags and plastic water bottles. An online survey is employed to gather data on the use and disposal of these plastic items and to solicit recommendations on how to positively change behavior to reduce improper disposal. Results support a ban on plastic bags and plastic water bottles, with more enthusiasm for a bag ban. Financial incentives are also seen as an effective way to influence behavior change, as are location-specific solutions focused on education and outreach.
Показать больше [+] Меньше [-]Hydrocarbon-degradation and MOS-formation capabilities of the dominant bacteria enriched in sea surface oil slicks during the Deepwater Horizon oil spill Полный текст
2018
Gutiérrez, Tony | Morris, Gordon | Ellis, Dave | Bowler, Bernard | Jones, Martin | Salek, Karina | Mulloy, Barbara | Teske, Andreas.
A distinctive feature of the Deepwater Horizon (DwH) oil spill was the formation of significant quantities of marine oil snow (MOS), for which the mechanism(s) underlying its formation remain unresolved. Here, we show that Alteromonas strain TK-46(2), Pseudoalteromonas strain TK-105 and Cycloclasticus TK-8 – organisms that became enriched in sea surface oil slicks during the spill – contributed to the formation of MOS and/or dispersion of the oil. In roller-bottle incubations, Alteromonas cells and their produced EPS yielded MOS, whereas Pseudoalteromonas and Cycloclasticus did not. Interestingly, the Cycloclasticus strain was able to degrade n-alkanes concomitantly with aromatics within the complex oil mixture, which is atypical for members of this genus. Our findings, for the first time, provide direct evidence on the hydrocarbon-degrading capabilities for these bacteria enriched during the DwH spill, and that bacterial cells of certain species and their produced EPS played a direct role in MOS formation.
Показать больше [+] Меньше [-]A critical review of marine snow in the context of oil spills and oil spill dispersant treatment with focus on the Deepwater Horizon oil spill Полный текст
2018
Brakstad, Odd G. | Lewis, Alun | Beegle-Krause, C.J.
Natural marine snow (NMS) is defined as the “shower” of particle aggregates formed by processes that occur in the world's oceans, consisting of macroscopic aggregates of detritus, living organisms and inorganic matter. Recent studies from the Deepwater Horizon oil spill suggest that marine snow is also formed in association with oil spills and was an important factor for the transport of oil to the seabed. This review summarizes the research and literature on MS, mainly from the DWH oil spill, with a focus on the relation between the use of oil spill dispersants and the formation and fate of oil-related marine snow (ORMS). Studies are still required to determine ORMS processes at oil concentrations as relevant as possible for chemically dispersed oil.
Показать больше [+] Меньше [-]Plastic ingestion by Tristram's Storm-petrel (Oceanodroma tristrami) chicks from French frigate shoals, Northwestern Hawaiian Islands Полный текст
2018
Youngren, Sarah M. | Rapp, Daniel C. | Hyrenbach, K David
This study provides the first quantification of plastic ingestion in the Tristram's Storm-petrel (Oceanodroma tristrami) in over 20 years. We found 100% plastic incidence in 57 chicks collected opportunistically over four breeding seasons (2007, 2010, 2011, 2012), with the mass of ingested plastic per individual ranging from 0.1 to 2.8 g (≤3.3% adult mass). While plastic occurred in every bird we examined, the proventriculus contained significantly more plastic, more fragments, and larger fragments than the gizzard. Most of the ingested plastic (97.5% by mass) consisted of fragments, ranging in length from 0.4 to 11.6 mm and ranging in surface area from 0.07 to 45.21 mm2. While fragments were ubiquitous, occurring in every proventriculus and gizzard we analyzed, Tristram's Storm-petrels also ingested foam, line and sheets. Digital analysis of 1425 ingested plastic fragments documented a wide range of colors, involving shades of white, yellow, orange, red, blue, green, and black.
Показать больше [+] Меньше [-]Marine sponges as a powerful tool for trace elements biomonitoring studies in coastal environment Полный текст
2018
Orani, Anna Maria | Barats, Aurélie | Vassileva, Emilia | Thomas, Olivier P.
In this work, we performed a comparative study on six marine sponge species collected along the French Mediterranean and Irish coasts for their TEs accumulation. Intra and inter-species variabilities were examined. Among the Mediterranean species, Cymbaxinella damicornis accumulates significantly more As and Cu than others sponge species; Chondrilla nucula more Ni and Mo and Acanthella acuta more Ag. Among Irish samples, Hymeniacidon perlevis showed higher accumulation properties for most of TEs in comparison to Halichondria panicea. Bioconcentration Factors were > 1 in all species for most of TEs. This study suggests that TEs bioaccumulation is most likely associated to differences in morphological features and/or to specific bacterial communities associated to different species. The determination of Pb isotope ratios revealed mainly natural Pb sources for Mediterranean and Kilkieran Bay's samples, and rather anthropogenic influence for Belfast samples. This study confirms that sponges represent a powerful tool for biomonitoring studies.
Показать больше [+] Меньше [-]Spatio-temporal variation of anthropogenic marine debris on Chilean beaches Полный текст
2018
Hidalgo-Ruz, Valeria | Honorato-Zimmer, Daniela | Gatta-Rosemary, Magdalena | Núñez Tomás, Paloma | Hinojosa, Iván A. | Thiel, Martin
We examined the hypothesis that in an emerging economy such as Chile the abundances of Anthropogenic Marine Debris (AMD) on beaches are increasing over time. The citizen science program Científicos de la Basura (“Litter Scientists”) conducted three national surveys (2008, 2012 and 2016) to determine AMD composition, abundance, spatial patterns and temporal trends. AMD was found on all beaches along the entire Chilean coast. Highest percentages of AMD in all surveys were plastics and cigarette butts, which can be attributed to local sources (i.e. beach users). The Antofagasta region in northern Chile had the highest abundance of AMD compared with all other zones. Higher abundances of AMD were found at the upper stations from almost all zones. No significant tendency of increasing or decreasing AMD densities was observed during the 8years covered by our study, which suggests that economic development alone cannot explain temporal trends in AMD densities.
Показать больше [+] Меньше [-]Fast pesticide pre-screening in marine environment using a green microalgae-based optical bioassay Полный текст
2018
Moro, Laura | Pezzotti, Gianni | Turemis, Mehmet | Sanchis, Josep | Farré, Marinella | Denaro, Renata | Giacobbe, Maria Grazia | Crisafi, Francesca | Giardi, Maria Teresa
The present study evaluates an optical bioassay based on green photosynthetic microalgae as a promising alternative for monitoring of relevant seawater pollutants. Photosystem II fluorescence parameters from several microalgae species were examined in the presence of three common marine pesticides that act as photosynthesis inhibitors. The three pollutants were detected within 10 min in concentrations between ng/L-μg/L. The different algae species showed slightly diverse pesticide sensitivities, being Chlorella mirabilis the most sensitive one. Potential interferences due to oil-spill pollutants were discarded. The lipid content was characterized to identify microorganisms with suitable mechanisms that could facilitate stress acclimatization. C. mirabilis presented elevated content of unsaturated lipids, showing a promising potential for biosensing in saline stress conditions.The optimized microalgae-based bioassay was preliminarily incorporated into a marine buoy for autonomous pre-screening of pesticides in coastal areas, demonstrating its suitability for real-time monitoring of marine water and quantitative evaluation of total biotoxicity.
Показать больше [+] Меньше [-]Diclofenac in the marine environment: A review of its occurrence and effects Полный текст
2018
Bonnefille, Bénilde | Gomez, Elena | Courant, Frédérique | Escande, Aurélie | Fenet, Hélène
Interest in the presence and effects of diclofenac (DCF) and other pharmaceutical products (PPs) in the aquatic environment has been growing over the last 20 years. DCF has been included in the First Watch List of the EU Water Framework Directive in order to gather monitoring data in surface waters. Despite PP input in water bodies, few studies have been conducted to determine the extent of DCF occurrence and effects on marine ecosystems, which is usually the final recipient of surface waters. The present article reviews available published data on DCF occurrence in marine water, sediment and organisms, and its effects on marine organisms. The findings highlight the scarcity of available data on the occurrence and effects of DCF in marine ecosystems, and the need for further data acquisition to assess the risks associated with the presence of this compound in the environment.
Показать больше [+] Меньше [-]Pesticide Pollution in Agricultural Soils and Sustainable Remediation Methods: a Review Полный текст
2018
Sun, Shixian | Sidhu, Virinder | Rong, Yuhong | Zheng, Yi
An increasing number of pesticides have been used in agriculture for protecting the crops from pests, weeds, and diseases but as much as 80 to 90% of applied pesticides hit non-target vegetation and stay as pesticide residue in the environment which is potentially a grave risk to the agricultural ecosystem. This review gives an overview of the pollution in agricultural soils by pesticides, and the remediation techniques for pesticide-contaminated soils. Currently, the remediation techniques involve physical, chemical, and biological remediation as well as combined ways for the removal of contaminants. The microbial functions in rhizosphere including gene analysis tools are fields in remediation of pesticide-contaminated soil which has generated a lot of interest lately. However, most of those studies were done in greenhouses; more research work should be done in the field conditions for proper evaluation of the efficiency of the proposed techniques. Long-term monitoring and evaluation of in situ remediation techniques should also be done in order to assess their long-term sustainability and practical applications in the field.
Показать больше [+] Меньше [-]Increased temperature but not pCO2 levels affect early developmental and reproductive traits of the economically important habitat-forming kelp Lessonia trabeculata Полный текст
2018
González, Claudio P. | Edding, Mario | Torres, Rodrigo | Manríquez, Patricio H.
The effects of ocean warming and ocean acidification on developmental and reproductive traits of Lessonia trabeculata were evaluated. Meiospores were cultured for 35 days in an experimental mesocosm where temperature (~15 and 19 °C) and partial CO2 pressure (pCO2, ~400 and 1300 μatm) were controlled. The results indicate that germination was reduced at 19 °C, whereas the increase of pCO2 only had effects at 15 °C. Likewise, the increase in temperature significantly affected the vegetative growth of female gametophytes. Sex ratio was not affected significantly by any of the variables studied. Fertility and reproductive success decreased by about 50% at 19 °C. The pCO2 levels had no significant effects on most early developmental traits. The results suggest that ocean warming or periodic warming events (e.g. an El Niño event) might affect the recruiting capacity of this or other similar species by affecting their early developmental stages.
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