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Degradation of BDE-47 in mangrove sediments with amendment of extra carbon sources
2020
Pan, Ying | Chen, Juan | Zhou, Haichao | Cheung, S.G. | Tam, Nora F.Y.
Polybrominated diphenyl ethers (PBDEs) are widely detected in coastal wetlands but their remediation is still difficult. In this study, different carbon sources, namely formate, acetate, pyruvate, lactate, succinate, methanol and ethanol, were added to mangrove sediments contaminated with BDE-47, a common PBDE congener, to enhance its degradation. After 2-month incubation, all carbon addition significantly enhanced degradation percentages. The residual BDE-47 percentage significantly correlated with the abundance of total bacteria and Dehalococcoides spp. The addition of methanol, acetate and succinate also achieved significantly higher degradation rates and shorter half-lives than sediments without carbon amendment at the end of 5-month incubation, although degradation percentages were comparable between sediments with and without extra carbon. The degradation pathway based on the profiles of degradation products was also similar among treatments. The results indicated the stimulatory effect of extra carbon sources on BDE-47 degradation in contaminated sediments was carbon- and time-specific.
显示更多 [+] 显示较少 [-]Α systematic meta-review analysis of review papers in the marine plastic pollution literature
2020
Aretoulaki, Eleni | Ponis, Stavros | Plakas, George | Agalianos, Konstantinos
The omnipresence of plastic particles in marine ecosystems, a.k.a. Marine Plastic Pollution (MPP) constitutes a major environmental and socioeconomic threat. In the last decade, the realization of the severity of the MPP problem by international organizations, governments and policy makers worldwide, has triggered the publication of a large number of review papers studying the current state of the art of MPP, from a plethora of different perspectives. This study attempts to classify the existing review efforts, by conducting a systematic analysis of review papers on MPP, published from 2000 to 2019. A sample of 114 review studies, retrieved from the SCOPUS database, are classified based on a number of carefully selected coding criteria and processed in order to produce a set of meaningful descriptive statistics and visualizations. Ultimately, the objective of this paper is to synthesize the different perspectives on MPP, assess the research progress and highlight future research directions.
显示更多 [+] 显示较少 [-]Assessment of microbial plankton diversity as an ecological indicator in the NW Mediterranean coast
2020
Ferrera, Isabel | Reñé, Albert | Funosas, David | Camp, Jordi | Massana, Ramon | Gasol, Josep M. | Garcés, Esther
High-throughput sequencing of microbial assemblages has been proposed as an alternative methodology to the traditional ones used in marine monitoring and environmental assessment. Here, we evaluated pico- and nanoplankton diversity as ecological indicators in NW Mediterranean coastal waters by comparing their diversity in samples subjected to varying degrees of continental pressures. Using metabarcoding of the 16S and 18S rRNA genes, we explored whether alphadiversity indices, abundance of Operational Taxonomic Units and taxonomic groups (and their ratios) provide information on the ecological quality of coastal waters. Our results revealed that only eukaryotic diversity metrics and a limited number of prokaryotic and eukaryotic taxa displayed potential in assessing continental influences in our surveyed area, resulting thus in a restrained potential of microbial plankton diversity as an ecological indicator. Therefore, incorporating microbial plankton diversity in environmental assessment could not always result in a significant improvement of current marine monitoring strategies.
显示更多 [+] 显示较少 [-]Microplastics on beaches along the eastern Gulf of Thailand – A preliminary study
2020
Bissen, Raphael | Chawchai, Sakonvan
Several studies have shown the ubiquitousness of microplastics across ecosystems worldwide including significant amounts in beach sand. In Thailand, however, there is a lack of studies about the microplastic pollution of beaches. This study aimed to quantify microplastics at the high-tide line of 21 beaches along the eastern Gulf of Thailand. Observed amounts ranged from 420 to >200,000 counts/kg. Anthropogenic and environmental factors affect distribution and amount of microplastics. Tide-dominated beaches and beach sections protected by beachrocks exhibit higher microplastic amounts due to lesser hydrodynamics. While human activities have a visible impact, in some cases environmental factors seem to predominate. Despite effective protection efforts led by the government and NGOs, our study shows that the substantial microplastic pollution of beach sand requires a proper management system with appropriate laws and regulations, and a public awareness campaign to reduce effects of microplastics on organisms and their ecosystems.
显示更多 [+] 显示较少 [-]Concentration and adsorption of Pb and Cu in microplastics: Case study in aquatic environment
2020
Purwiyanto, Anna Ida Sunaryo | Suteja, Yulianto | Trisno, | Ningrum, Putri Sampurna | Putri, Wike Ayu Eka | Rozirwan, | Agustriani, Fitri | Fauziyah, | Cordova, Muhammad Reza | Koropitan, Alan Frendy
Microplastics are proven as heavy metals vector, but the adsorption mechanism still unclear. This study investigated the adsorption of Pb and Cu in microplastics in the Musi River and the environment effect. This study was conducted in 10 stations along the Musi River to the estuary. The polymers of microplastics were dominated by PP and followed by PE, PES, PVC, and nylon. The average concentration of Pb (0.0347 mg L⁻¹ for water and 0.470 mg kg⁻¹ for microplastics) was higher than Cu (0.0138 mg L⁻¹ for water and 0.091 mg kg⁻¹ for microplastics). The highest concentration of both metals in water and microplastics were found in the estuary. Environment parameters have different effects on the adsorption. The present study found that the adsorption processes were following the Freundlich model. The interaction metal-microplastic was physisorption. Pb and Cu will attach through weak bonds and easy to release into the aquatic ecosystem.
显示更多 [+] 显示较少 [-]Warm temperature alters the chemical cue preference of Acropora tenuis and Heliopora coerulea larvae
2020
Da-Anoy, Jeric P. | Cabaitan, Patrick C. | Conaco, Cecilia
Larvae released into the water column rely on chemical cues from the benthos for successful settlement. However, larval preference for substrates may be affected by rising seawater temperature brought about by global climate change. In this study, we examined the effect of elevated temperature on chemical cue preference by larvae of the scleractinian coral, Acropora tenuis, and the octocoral, Heliopora coerulea, collected from northwestern Philippines. At ambient temperature (28 °C), both H. coerulea and A. tenuis larvae showed preference for substrates containing either crustose coralline algae or crude ethanolic extracts from conspecific or congeneric corals. In contrast, at higher temperature (30 °C), greater preference was shown for substrates containing the crude extract from conspecific or congeneric corals. These results demonstrate that elevated temperature can change larval substrate preference, which will have downstream impacts on crucial biological processes, such as larval settlement and recruitment.
显示更多 [+] 显示较少 [-]Observation of microplastics in mariculture water of Longjiao Bay, southeast China: Influence by human activities
2020
Chen, Bin | Fan, Yingping | Huang, Wei | Rayhan, A.B.M Sadique | Chen, Kai | Cai, Minggang
The fishery and mariculture industry contributes to social food supply and offers high-quality protein to humans. However, mariculture is recently regarded as an important source of marine microplastic pollution, which might even pose a threat to human health. Here we investigated a shrimp-culturing farm for 9 months in Longjiao Bay, a typical mariculture area in southeast China, to study the occurrence and seasonal variations of microplastics in the mariculture water. Results showed that microplastics were widely present (250–5150 particles/m³, mean 1594 particles/m³) in the water of culture ponds. Granules (41.36%) and fibers (34.93%) were the main components of microplastics and white (45.42%) is the dominant color, followed by yellow (32.13%) and black (19.55%). Most of microplastics had a particle size between 0.30 mm and 5.00 mm (92.03%). The proportions of PE (34.40%) and PET (30.18%) accounted for more than 60% of detected microplastics. The abundance of microplastics in mariculture water had a potential positive correlation with local seafood yield and a negative correlation with land areas. This study suggested that further research is needed to figure out the impact of the high levels of microplastic abundance in mariculture environments on organisms, especially cultured ones.
显示更多 [+] 显示较少 [-]The invasive species Perna viridis (Linnaeus, 1758 - Bivalvia: Mytilidae) on artificial substrates: A baseline assessment for the Colombian Caribbean Sea
2020
Gracia C., Adriana | Rangel-Buitrago, Nelson
This baseline paper shows the Indo-Pacific mussel Perna viridis (Asian green mussel) inhabiting on floating plastic substrates in the Atlantico Department, as well as rafting on marine debris found at the Via Parque Isla de Salamanca (Magdalena). Both observations are the northernmost record of the species found in the Colombian Caribbean Sea. The above finding opens a new door that suggests that larval dispersion alone may not be the only process responsible for the presence of this invasive suspension-feeder bivalve because this species needs specific vectors for its dispersal. Some organisms such Perna viridis can persist in the marine environment, but they do not necessarily have a rafting capability that allows them to move over long distances. Floating structures as well as marine debris can serve as optimal substrates in the marine environment, contributing to an increase in the problems of non-native species on sites with a high degree of susceptibility to species invasion.
显示更多 [+] 显示较少 [-]Changes in feeding habits of the starspotted smooth-hound, Mustelus manazo, in Tokyo Bay between periods with different stock size levels
2020
Park, Jeong-Chae | Kodama, Keita | Oyama, Masaaki | Lee, Jeong Hoon | Ohta, Yasuhiko | Yamaguchi, Atsuko | Shiraishi, Hiroaki | Horiguchi, Toshihiro
We investigated differences in the feeding habits of the starspotted smooth-hound, Mustelus manazo, in Tokyo Bay between the mid-1990s (low stock size) and the late 2000s (high stock size). The frequency of M. manazo with empty stomachs increased from 5.9% in the mid-1990s to 16.1% in the late 2000s. A decrease in the relative weight of the stomach contents was evident from the mid-1990s to the late 2000s, especially in the small size classes, along with changes in the species composition in the stomach contents. Although crustaceans were the main constituents of the stomach contents, the proportion of crabs increased while those of shrimps and hermit crabs decreased. Changes in the feeding habits of M. manazo may be associated with shifts in the benthic community structure in Tokyo Bay.
显示更多 [+] 显示较少 [-]Making sense of microplastics? Public understandings of plastic pollution
2020
Henderson, Lesley | Green, Christopher
This paper explores people's knowledge and understandings of microplastics; the role of media in framing perceptions and socio-cultural dimensions to popular solutions to reduce single-use plastics. We conducted 6 focus groups (2016–17) involving participants with no obvious knowledge of microplastics and some with special interest. Most people were unaware of microplastics though environmentally conscious participants had heard of microbeads due to media reporting concerning regulation. Few made connections between their personal use of plastics and ocean pollution. Plastic pollution was associated with macro-plastic ‘islands’ in the Great Pacific Garbage Patch and powerful media images of charismatic wildlife entanglement remote from participants lives. The scale of microplastics (not easily detected), poor understanding of the science behind microplastics and cultural ideas about healthy and appropriate behaviour presents barriers to change. Science communicators, NGOs, industry and policy makers must take account of media representations and the culturally embedded nature of plastics in society.
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