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Plasticrusts derive from maritime ropes scouring across raspy rocks Texto completo
2021
Ehlers, Sonja M. | Ellrich, Julius A. | Gestoso, Ignacio
Plasticrusts are a novel form of plastic debris which has only recently been discovered in Madeira Island, NE Atlantic Ocean. Plasticrusts consist of plastic encrusting wave-exposed rocky intertidal habitats and are presumably generated by waves smashing plastic debris against intertidal rocks. However, direct observations of this process are lacking and it is unknown which type of plastic debris the plasticrusts derive from. Therefore, we examined the Madeira rocky intertidal for signs of plasticrust formation and collected plasticrust and co-occurring plastic debris pieces of matching colors. We examined all collected materials using digital microscopy and Fourier-transform infrared spectroscopy. We found that plasticrusts can result from maritime ropes being scoured across raspy intertidal rocks and that the plasticrusts and the corresponding ropes consisted of polypropylene (PP) and high-density polyethylene (HDPE). Furthermore, we show that high temperatures contribute to plasticrust formation. Thereby, our study provides first insights into the complex plasticrust formation process.
Mostrar más [+] Menos [-]Pathogenic hitchhiker diversity on international ships' ballast water at West Malaysia port Texto completo
2021
Salleh, Nor Aishah | Rosli, Farah Nadiah | Akbar, Muhamad Afiq | Yusof, Aqilah | Sahrani, Fathul Karim | Razak, Shairah Abdul | Ahmad, Asmat | Usup, Gires | Bunawan, Hamidun
This study investigates bacterial diversity and potential pathogens in the international ships' ballast water at Tanjung Pelepas Port, Malaysia, using 16S rRNA amplicon sequencing. Thirty-four bacterial phylum, 305 families, 577 genera, and 941 species were detected in eight ballast water samples of different origins. The similarity of the bacterial composition between samples was found to be random and not tied to geographical locations. The bacterial abundance did not seem to be affected by related physicochemical except for temperature. Ballast water samples with a temperature lower than 25 °C showed a relatively lower bacterial abundance. A total of 33 potential pathogens were detected from all ballast water samples. Pseudomonas spp., Tenacibaculum spp., Flavobacteriaceae spp., Halomonas spp., and Acinetobacter junii are the potential pathogens with more than 10% OTU prevalence. This study would provide beneficial information for further enhancing ballast water microorganism guidelines in Malaysia.
Mostrar más [+] Menos [-]Coronavirus survival on beach sand: Sun vs COVID-19 Texto completo
2021
Efstratiou, Maria Adamantia | Tzoraki, Ourania
The disinfecting properties of sun (heat and UV radiation) are adequate in warm sunny regions to rid beach sand of coronavirus particles, if present. Here we detail the mechanism of natural disinfection offered by the sun on coronaviral particles that may find their way onto beach sand. We conclude that heat and UV radiation generated by the sun destroy the virus infection ability.
Mostrar más [+] Menos [-]Age frequency, growth, mortality, and PAH levels of roughtongue bass (Pronotogrammus martinicensis) following the Deepwater Horizon oil spill Texto completo
2021
Biermann, Lindsay K. | Szedlmayer, Stephen T.
Age, growth, mortality, and polycyclic aromatic hydrocarbons (PAHs) in roughtongue bass (Pronotogrammus martinicensis) were examined in the northern Gulf of Mexico following the 2010 Deepwater Horizon oil spill. Fish (N = 1090) were collected from September 2014 to July 2015 from the Alabama Alps (54 km from the spill site) and Roughtongue Reef (111 km from the spill site). Sites were dominated by the 2010 year-class. Growth rates were significantly lower for fish from Alabama Alps compared to Roughtongue Reef (p < 0.001) and likely linked to proximity of the Mississippi River discharge. Mean total PAH ± SD was 50 ± 52.6 and ranged from 0 to 220 ppb. These PAH levels were below a 300-ppb minimum effect level and not significantly different between sites. The dominant 2010 year-class, low PAH levels, and similar growth rates to pre-spill measures indicated that the Deepwater Horizon oil spill had little effect on roughtongue bass.
Mostrar más [+] Menos [-]The genome of the European estuarine calanoid copepod Eurytemora affinis: Potential use in molecular ecotoxicology Texto completo
2021
Choi, Beom-Soon | Kim, Duck-Hyun | Kim, Min-Sub | Park, Jun Chul | Lee, Young-Hwan | Kim, Hee-Jin | Jeong, Chang-Bum | Hagiwara, A. (Atsushi) | Souissi, Sami | Lee, Jae-seong
In this study, we sequenced and assembled the genome of a European estuarine calanoid copepod using Oxford Nanopore PromethION and Illumina HiSeq 2500 platforms. The length of the assembled genome was 776.1 Mb with N50 = 474.9 kb (BUSCO 85.9%), and the genome consisted of 2473 contigs. A total of 18,014 genes were annotated and orthologous gene clusters were analyzed in comparison to other copepods. In addition, genome-wide identification of cytochrome P450s, glutathione S-transferases, and ATP-binding cassette transporters in E. affinis was performed to determine gene repertoire of these detoxification-related gene families. Results revealed the presence of species-specific gene inventories, indicating that these gene families have evolved through species-specific gene loss/expansion processes, possibly due to adaptation to different environmental stressors. Our study provides a new inventory of the European estuarine calanoid copepod E. affinis genome with emphasis on phase I, II, and III detoxification systems.
Mostrar más [+] Menos [-]An optimized procedure for extraction and identification of microplastics in marine sediment Texto completo
2021
Liu, Yandong | Gao, Fenglei | Li, Zhaozhao | Ding, Huiping | Zhang, Dahai | Feng, Lijuan | Li, Xianguo
Microplastics (MPs) in sediment environments have been widely reported. As the number of samples increases, establishing a reliable and effective method becomes increasingly urgent for the rapid extraction and identification of MPs in sediments. Herein, we proposed a system with continuous density flotation of NaBr-ZnCl₂ (mixture of NaBr and ZnCl₂) solution for extracting MPs in a sediment sample, combined with micro-Fourier transform infrared (μ-FT-IR) imaging scanning for identification of MPs. The recoveries of MPs were estimated for four different sizes, shapes, and ten different types of polymers. The results indicated NaBr-ZnCl₂ solution showed a high recovery rate from 88.33% to 100.00% for extracting these different MPs. The μ-FT-IR imaging scanning allows for the detection of plastic down to the size of 6.25 μm in filed samples, and merely takes about 3 min, which was validated by testing of sediments from Jiaozhou Bay, China and its adjacent estuaries.
Mostrar más [+] Menos [-]On mobulid rays and metals: Metal content for the first Mobula mobular record for the state of Rio de Janeiro, Brazil and a review on metal ecotoxicology assessments for the Manta and Mobula genera Texto completo
2021
Hauser-Davis, Rachel Ann | Amorim-Lopes, Catarina | Araujo, Nathan Lagares Franco | Rebouças, Manasi | Gomes, Ricardo Andrade | Rocha, Rafael Christian Chávez | Saint'Pierre, Tatiana Dillenburg | dos Santos, Luciano Neves
This study comprises the first record of a juvenile Giant Devil Ray specimen for Rio de Janeiro, Southeastern Brazil, and its metal and metalloid contents. A scientometric assessment was also performed for the Manta and Mobula genera. Only five records were found, and only As, Cd, Pb, Hg, Pt, Pd and Rh have been assessed. All studies but one concerned human consumption. A significant knowledge gap on metal and metalloid ecotoxicology for mobulid rays is noted, indicating the emergence of a new field of research that th may be applied for wildlife conservation and management in response to anthropogenic contamination. Our study is also the first to provide Al, Cr, Cu, Fe, Mn, Sr, Ti, V and Zn contents for muscle, liver, brain and kidney for a mobulid ray and one of the scarce reports concerning As, Cd, Hg and Pb in muscle, liver and kidney.
Mostrar más [+] Menos [-]Persistent organic pollutant (POPs) concentrations from great-winged petrels nesting in Western Australia Texto completo
2021
Gilmour, Morgan E. | Lewis, Phoebe J. | Paige, Tanya | Lavers, Jennifer L.
Marine animals that traverse coastal and offshore environments are potentially exposed to multiple sources of pollution. Baseline data of pollutant concentrations of these fauna are needed in remote areas as human populations grow and economic development increases because changes may affect local wildlife in unforeseen ways. Persistent organic pollutant (POPs) concentrations were quantified in an understudied seabird, the great-winged petrel (Pterodroma macroptera), that breeds in southern Western Australia. Organochlorine pesticides, polychlorinated biphenyls (PCBs), and novel brominated flame retardants (NBFRs) were measured in adults. Total POPs concentrations ranged 5.6–46.4 ng g⁻¹ ww. The most frequently detected POPs were the dichlorodiethyltrichloroethane (DDT) metabolite 4,4'DDE, the PCB CB-28, and the BFR polybrominated diphenyl ether BDE-99. These results contribute to the limited POPs data in marine fauna in this remote region, and the Southern Hemisphere, adding to the growing body of evidence that remote regions are affected by global trends of POPs distributions.
Mostrar más [+] Menos [-]In the business of dirty oceans: Overview of startups and entrepreneurs managing marine plastic Texto completo
2021
Dijkstra, Hanna | Beukering, Pieter van | Brouwer, Roy
Plastic pollution, especially in marine environments, is a global problem that is currently inadequately managed. Solutions for marine plastic can occur through policy, behavior change and infrastructure improvements, but also through entrepreneurial ventures and technological innovations. Currently, information about these ventures and innovations is scattered and lacks coherence. This study presents the first comprehensive overview of entrepreneurial and SME led solutions for marine plastic by analyzing a database of 105 SMEs categorized into four functions: prevention, collection, transformation and monitoring. We find that small businesses are successfully commercializing goods and services to reduce the damage of plastics on the marine environment through innovative business models, with a steep growth of startups founded between 2016 and 2019. However, efforts to manage marine plastic are still underdeveloped in many areas, including microplastic management and monitoring. Practitioners, policymakers and researchers can utilize the database to identify solutions, best practices, synergies and avenues for further research, such as quantifying the environmental impacts of this industry.
Mostrar más [+] Menos [-]The effectiveness of legislative and voluntary strategies to prevent ocean plastic pollution: Lessons from the UK and South Pacific Texto completo
2021
Tudor, David T. | Williams, Allan T.
The islands of the South Pacific contribute a fraction of the mis-managed plastics in the world's ocean, yet the region is one of the main recipients of its impacts. Based on expert interviews and a review of current strategies to prevent marine plastic pollution in six countries (Australia, New Zealand, Fiji, Tonga, Vanuatu, United Kingdom), this paper identifies several interventions – legislative, financial, voluntary - which governments, organisations and individuals can learn from. Both voluntary and statutory consumer-based behaviour change campaigns are well developed and somewhat successful in several countries. While sub-national policies do not inhibit progress, they are not optimal. Harmonisation across the territories of federal and devolved systems is beneficial, such as container return schemes, levies, and bans. Vanuatu has displayed high ambition, and the challenges in achieving this serve as a case study. A coordinated global strategy with associated legislation aimed at tackling plastic pollution is critical.
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