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Marine debris in Indonesia: A review of research and status Полный текст
2019
Purba, Noir P. | Handyman, Dannisa I.W. | Pribadi, Tri D. | Syakti, Agung D. | Pranowo, Widodo Setiyo | Harvey, Andrew | Ihsan, Yudi N.
With the status as the world's top contributor of marine plastic debris, Indonesia has committed to reduce marine plastic debris up to 70% in 2025 by establishing the National Action Plan (NAP) on Marine Debris. The high amount of marine plastic debris as a result of transport and accumulation become a complex issue in Indonesia due to its ocean-atmospheric circulation, high population of coastal communities, and marine activities. Based on our findings, there are gap of publications related to marine debris in Indonesia that had been already published. Marine debris is ubiquitous and transboundary, as they were found in marine environment and transported by currents to various direction including uninhabited islands, thus, we propose more comprehensive future research about the impact of marine debris on ecosystem (e.g. biological impact of organisms in the water column, ecological alteration in distribution pattern, and invasive species), human health, and economic loss.
Показать больше [+] Меньше [-]Fate of residual oils during remediation activities after the Wu Yi San oil spill Полный текст
2019
Loh, Andrew | Yim, Un Hyuk | Ha, Sung Yong | An, Joon Geon | Shankar, Ravi
In this study, the fate of residual oils was investigated during remediation activities for a year after the Wu Yi San oil spill. Microscope observations showed that relatively large amounts of oil-suspended particulate matter aggregate (OSA) were formed. Negatively buoyant OSA was the dominant form (>95%), followed by neutrally (~5%) and positively buoyant (<1%) forms. To elucidate the dominance of negative buoyancy OSA, physicochemical properties of the mineral and residual oils were identified. Chemical analysis showed that the weathering percentage of residual oils was 43.7 ± 2.59%, which was the driving factor for sedimentation of OSA. As the density of oil increased with weathering stages, the density of OSA also increased simultaneously. These results showed that, during mechanical remediation activities, resurfaced residual oils can form negative buoyancy OSA which tends to sink and transfers oil contaminants from intertidal to benthic environments.
Показать больше [+] Меньше [-]Quantification is more than counting: Actions required to accurately quantify and report isolated marine microplastics Полный текст
2019
Rivers, Molly L. | Gwinnett, Claire | Woodall, Lucy C.
Research on marine microplastics continues to increase in popularity, with a large number of studies being published every year. However, with this plethora of research comes the need for a standardised approach to quantification and analysis procedures in order to produce comparative assessments. Using data collected from neuston nets in 2016, parameters for quantifying microplastics were compared. Surface area was the most accurate parameter to describe plastic size and should be used to describe plastic quantity (per km2 or m3), alongside abundance. Of the two most commonly used methods for calculating plastic concentration (flowmeter and ship's log), ship's log provided consistently smaller abundances, with the exception of one sample, calling for a standardisation in the techniques and measurements used to quantify floating microplastics.
Показать больше [+] Меньше [-]Effects of polycyclic aromatic hydrocarbons on the UV-induced fluorescence spectra of crude oil films on the sea surface Полный текст
2019
Hou, Yongchao | Li, Ying | Liu, Yu | Li, Guannan | Zhang, Zhenduo
As the main fluorescent substances in oils, polycyclic aromatic hydrocarbons (PAHs) are the basis of ultraviolet (UV)-induced fluorescence spectroscopy methods to detect oil films on the sea surface. The relative contents of PAHs in six crude oil samples and their effects on ultraviolet fluorescence spectra were studied. The PAHs were divided into four categories according to their fluorescence characteristics. Naphthalene series dominated the fluorescence spectra, which led to a main peak at 320–350 nm, but this showed no relationship with PAH content. The six oil samples could not be distinguished by differences in the fluorescence spectra in this range, but could be distinguished by the fluorescence spectra in the 350–380 nm band. The relative contents of dibenzothiophene and phenanthrene series showed significant positive correlations (R² = 0.96) with fluorescence intensity. Fluorescence spectroscopy combined with GC–MS can be used to distinguish and identify crude oils.
Показать больше [+] Меньше [-]Environmental implications of microplastic pollution in the Northwestern Pacific Ocean Полный текст
2019
Pan, Zhong | Liu, Qianlong | Sun, Yan | Sun, Xiuwu | Lin, Hui
Microplastics (MPs) contamination has been recognized as one of major threats to coastal marine environments. Although studies evidenced severe MPs contaminations to the Pacific Ocean, environmental implications of MPs concentrations, distributions, and characteristics have not been evaluated in sufficient detail. Here, we report on the distribution, abundance, and characteristics of MPs at the surface of the Northwestern Pacific Ocean, from which environmental implications are assessed. A manta trawl with a mesh size of ~330 μm and a rectangular net opening of 0.45 × 1 m was used to collect MPs samples on May 11–June 3, 2018. The MPs samples were sequentially isolated, digested, filtered, and characterized using an optical microscope, micro-Raman spectroscopy, and scanning electron microscopy. The results indicate the heterogeneity in abundance, shapes, color, and sizes of MPs. The study provides strong environmental implications such as sources, environmental degradation, residence time, transportation routes, and biological interactions.
Показать больше [+] Меньше [-]Incidence of plastic ingestion in seabirds from the Bay of Biscay (southwestern Europe) Полный текст
2019
Franco, Javier | Fort, Jerome | García-Barón, Isabel | Loubat, Pauline | Louzao, Maite | del Puerto, Oihane | Zorita, Izaskun
Seabirds have been widely used to monitor marine debris by the analysis of plastic ingestion. With the aim of obtaining the first data on ingestion of plastics by different seabird species in the Bay of Biscay and evaluating their suitability as biomonitors of plastic pollution in this area, a total of 159 seabirds of fifteen species were analyzed. Plastics were found in 26 birds (16% of the individuals) of nine species (60% of the species). Frequency of occurrence of plastics varied between 0% (Razorbill) and 100% (species of the family Procellariidae). Considering several criteria to assess their suitability as biomonitors of plastic pollution (frequency of occurrence of plastic ingestion, species abundances and stranding occurrence in the Bay of Biscay), the Common Guillemot and the Atlantic Puffin seem the most promising candidates. This study provides the first data on plastic ingestion in seabirds of the Bay of Biscay.
Показать больше [+] Меньше [-]Biodegradation of crude oil using self-immobilized hydrocarbonoclastic deep sea bacterial consortium Полный текст
2019
Ganesh Kumar, A. | Nivedha Rajan, N. | Kirubagaran, R. | Dharani, G.
Hydrocarbonoclastic bacterial consortium that utilizes crude oil as carbon and energy source was isolated from marine sediment collected at a depth of 2100 m. Molecular characterization by 16S rRNA gene sequences confirmed that these isolates as Oceanobacillus sp., Nesiotobacter sp., Ruegeria sp., Photobacterium sp., Enterobacter sp., Haererehalobacter sp., Exiguobacterium sp., Acinetobacter sp. and Pseudoalteromonas sp. Self-immobilized consortium degraded more than 85% of total hydrocarbons after 10 days of incubation with 1% (v/v) of crude oil and 0.05% (v/v) of Tween 80 (non-ionic surfactant) at 28 ± 2 °C. The addition of nitrogen and phosphorus sources separately i.e. 0.1% (v/v) of CO (NH₂)₂ or K₂HPO₄ enhanced the hydrocarbon utilization percentage. The pathways of microbial degradation of hydrocarbons were confirmed by FTIR, GC–MS, ¹H and ¹³C NMR spectroscopy analyses. These results demonstrated a novel approach using hydrocarbonoclastic self-immobilized deep sea bacterial consortium for eco-friendly bioremediation.
Показать больше [+] Меньше [-]Human mastadenovirus in water, sediment, sea surface microlayer, and bivalve mollusk from southern Brazilian beaches Полный текст
2019
Gularte, Juliana Schons | Girardi, Viviane | Demoliner, Meriane | de Souza, Fernanda Gil | Filippi, Micheli | Eisen, Ana Karolina Antunes | Mena, Kristina D. | de Quevedo, Daniela Muller | Rigotto, Caroline | de Barros, Marcelo Pereira | Spilki, Fernando Rosado
Anthropogenic contamination of beaches in the south of Brazil was assessed by detection of Escherichia coli, human mastadenovirus species C (HAdV-C) and F (HAdV-F) and hepatitis E virus (HEV). Sampling was carried out in October (2016), and in January, April and July (2017). Water, sediment, sea surface microlayer (SML), bivalves, and air sentinel samples were evaluated. Quantitative microbiological risk assessment (QMRA) was used to estimate the probability of swimmer infection. HAdV-C was present in 26% of the samples, for both qPCR and viral isolation. The highest rates of detection in genomic copies (GC) were in water (2.42E+10 GC/L), SML (2.08E+10 GC/L), sediment (3.82E+08 GC/g) and bivalves (3.91E+07 GC/g). QMRA estimated daily and annual risks with a maximum value (9.99E-01) in almost all of the samples. Viable HAdV-C was often detected in the SML, pointing that this is a source of infection for people bathing in these waters.
Показать больше [+] Меньше [-]Damping of surface waves due to crude oil/oil emulsion films on water Полный текст
2019
Sergievskaya, Irina | Ermakov, Stanislav | Lazareva, Tatyana | Guo, Jie
In this paper results of laboratory studies of damping of gravity-capillary waves due to emulsified oil films (EOF) are presented and compared to crude oil films (COF). A laboratory method based on measuring the damping coefficient and the length of parametrically generated gravity-capillary waves is applied to a 50% EOF and to crude oil films. Measurements of wave damping were carried out in a range of surface wave lengths, corresponding to Bragg waves of X- to Ka-band radars. The obtained dependences of wave damping coefficient on EOF thickness have demonstrated the existence of a damping maximum at thicknesses of about 1–2 mm, and the maximum is approximately twice the one for COF, the damping maximum for EOF is located at larger film thicknesses than for COF. Theoretical calculations of wave damping have been performed and viscoelastic parameters of EOF have been estimated from comparison between theory and experiment.
Показать больше [+] Меньше [-]Assessing chemical contamination in the coastal waters of the Adriatic Sea using active mussel biomonitoring with Mytilus galloprovincialis Полный текст
2019
Bajt, Oliver | Ramšak, Andreja | Milun, Vesna | Andral, Bruno | Romanelli, Giulia | Scarpato, Alfonso | Mitrić, Milena | Kupusović, Tarik | Kljajić, Zoran | Angelidis, Michael | Ҫullaj, Algi | Galgani, François
The MYTIAD project focused on the assessment of chemical contamination (metals, PAHs, PCBs and organochlorine pesticides) in the Adriatic coastal waters by active mussel watching. Its purpose was harmonising and standardising strategies and methodologies used to assess the contamination status of the Adriatic Sea, in the framework of the WFD, the MSFD and UNEP/MAP Integrated Monitoring and Assessment Programme. Data on metals pointed out some hotspots along the eastern and western Adriatic Sea coasts, with the highest values of total PAH concentration detected in Split, Trieste, and Taranto (Ionian Sea). PCB and endrin contamination was higher in the Adriatic Sea than in the western Mediterranean Sea. This is the first comprehensive overview of contamination in the Adriatic Sea with critical comparisons of related studies over the Mediterranean Sea. It provides a useful harmonised dataset to support a coordinated definition of baselines, targets and thresholds, and further management of chemical contamination.
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