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Sponge-microbe partnerships are stable under eutrophication pressure from mariculture Texto completo
2018
Baquiran, Jake Ivan P. | Conaco, Cecilia
Sponges harbor a great diversity of symbiotic microorganisms. However, environmental stresses can affect this partnership and influence the health and abundance of the host sponges. In Bolinao, Pangasinan, Philippines, chronic input of organic materials from mariculture activities contributes to a eutrophic coastal environment. To understand how these conditions might affect sponge-microbial partnerships, transplantation experiments were conducted with the marine sponge Gelliodes obtusa. High-throughput sequencing of 16S rRNA revealed that the associated microbial community of the sponges did not exhibit significant shifts after six weeks of transplantation at a eutrophic fish farm site compared to sponges grown at a coral reef or a seagrass area. However, sponges at the fish farm revealed higher abundance of the amoA gene, suggesting that microbiome members are responsive to increased ammonium levels at the site. The stable association between G. obtusa and its microbiome indicates that the sponge holobiont can withstand eutrophication pressure from mariculture.
Mostrar más [+] Menos [-]Concentrations of polycyclic aromatic hydrocarbons in liver samples of juvenile green sea turtles from Brazil: Can these compounds play a role in the development of fibropapillomatosis? Texto completo
2018
Vilca, Franz Zirena | Rossi, Silmara | de Olinda, Ricardo Alves | Sánchez-Sarmiento, Angélica Maria | Prioste, Fabíola Eloisa Setim | Matushima, Eliana Reiko | Tornisielo, Valdemar Luiz
Fibropapillomatosis (FP) poses a significant threat to the conservation of green sea turtles (Chelonia mydas). Polycyclic aromatic hydrocarbons-PAHs are considered mutagenic, carcinogenic and toxic, and can act as cofactor of this disease. In order to evaluate possible differences between green sea turtles with and without FP, we monitored 15 PAHs in liver samples of 44 specimens (24 with FP) captured in Brazil. We detected eight PAHs and quantified phenanthrene in all green sea turtles with FP. Specimens without FP presented lower values than the tumored ones (1.48 ng g−1 and 17.35 ng g−1, respectively; p < 0.0001). There were no significant differences between tumored and non-tumored specimens, among studied areas, or Southwest Atlantic Fibropapillomatosis Score. Even though we found higher concentrations in the liver samples of green sea turtles with FP, further studies are necessary to confirm if these pollutants are involved in the pathogenesis of the disease.
Mostrar más [+] Menos [-]Ingestion of microplastic debris by green sea turtles (Chelonia mydas) in the Great Barrier Reef: Validation of a sequential extraction protocol Texto completo
2018
Caron, Alexandra G.M. | Thomas, Colette R. | Berry, Kathryn L.E. | Motti, Cherie A. | Ariel, Ellen | Brodie, J. E. (Jon E.)
Ocean contamination by plastics is a global issue. Although ingestion of plastic debris by sea turtles has been widely documented, contamination by microplastics (<5mm) is poorly known and likely to be under-reported. We developed a microplastic extraction protocol for examining green turtle (Chelonia mydas) chyme, which is multifarious in nature, by modifying and combining pre-established methods used to separate microplastics from organic matter and sediments. This protocol consists of visual inspection, nitric acid digestion, emulsification of residual fat, density separation, and chemical identification by Fourier transform infrared spectroscopy. This protocol enables the extraction of polyethylene, high-density polyethylene, (aminoethyl) polystyrene, polypropylene, and polyvinyl chloride microplastics >100μm. Two macroplastics and seven microplastics (two plastic paint chips and five synthetic fabric particles) were isolated from subsamples of two green turtles. Our results highlight the need for more research towards understanding the impact of microplastics on these threatened marine reptiles.
Mostrar más [+] Menos [-]Qualification of oil-spill treatment products – Adopting the Baffled Flask Test for testing of dispersant efficacy in the UK Texto completo
2018
Sühring, Roxana | Smith, Andy | Emerson, Heather | Doran, Denise | Mellor, Phil | Kirby, Mark F. | Christie, Bernard
The UK Marine Management Organisation (MMO) tasked the Centre for Environment, Fisheries & Aquaculture Science (Cefas) with reviewing the current UK dispersant efficacy testing procedures. The aim was to identify possibilities to increase standardisation, improve health and safety performance and explore harmonisation possibilities with international dispersant efficacy testing procedures. The US EPA ‘Baffled Flask Test’ (BFT) was adopted, implemented and validated as a new standard method in the UK. The outputs from this study suggest that dispersant efficacy results from the adopted BFT test and the currently used protocol are in a similar range and results presented by the US EPA.As a result, the transition to the adopted BFT test will require minimal changes in the assessment of the results or reporting and increase harmonisation between tests used in the UK and North America.
Mostrar más [+] Menos [-]Insights of the Removal Mechanisms of Pharmaceutical and Personal Care Products in Constructed Wetlands Texto completo
2018
Vo, Hoang-Nhat-Phong | Bui, Xuan-Thanh | Nguyen, Thi-Minh-Hong | Koottatep, T. | Bandyopadhyay, Amitava
PURPOSE OF REVIEW: Pharmaceutical and personal care products (PPCPs) are chemicals employed in human healthcare, veterinary, medical diagnosis, and cosmetics, which have increasingly polluted water sources. Extensive research has demonstrated constructed wetlands (CWs) technology as a low-cost but efficient approach for PPCPs removal. There has been a growing interest to better understand the degradation mechanisms of PPCPs in wetland cells. Data corroborated in this review show that these degradation mechanisms include photolytic degradation, adsorption, phytodegradation, and microbial degradation. Each of these degradation mechanisms performs differently in wetland cells. This review also highlights the lack of research works to quantify the contribution of these degradation mechanisms to the overall efficiency of CWs to remove PPCPs as a major bottleneck for further application of this technology. The ultimate goal is to apply and prioritize a suitable degradation mechanism for successfully eliminating corresponding PPCPs. This review, therefore, provides further insights to (i) elucidate the importance of these removal mechanisms, and (ii) quantify their contribution in overall PPCPs removal processes. This review aims to understand the importance and contribution of degradation mechanisms of PPCPs removal in constructed wetlands. RECENT FINDINGS: The degradation mechanisms of PPCPs in constructed wetlands depended on various conditions; yet, which factors are preferred? Furthermore, the number of research works, related to quantifying the contribution of degradation mechanisms, is limited. The hydrophobic/hydrophilic character, reflecting as log Kₒw (or log Dₒw), is the most commonly used. The photolytic degradation is appropriate with low and moderate hydrophobic values (log Dₒw from − 2.3 to 3). The role of adsorption is moderate, while it is more efficient with the higher hydrophobic compounds. The media is important for plant growth and micro-organism community development. The plant uptake is better for PPCPs with higher hydrophobicity (log Kₒw from 1 to 4). However, it is difficult to quantify their contribution and the number of related studies is limited.
Mostrar más [+] Menos [-]Crowdsourcing conservation: The role of citizen science in securing a future for seagrass Texto completo
2018
Jones, Benjamin L. | Unsworth, Richard K.F. | McKenzie, Len J. | Yoshida, Rudi L. | Cullen-Unsworth, Leanne C.
Seagrass meadows are complex social-ecological systems. Understanding seagrass meadows demands a fresh approach integrating “the human dimension”. Citizen science is widely acknowledged for providing significant contributions to science, education, society and policy. Although the take up of citizen science in the marine environment has been slow, the need for such methods to fill vast information gaps is arguably great. Seagrass meadows are easy to access and provide an example of where citizen science is expanding. Technological developments have been pivotal to this, providing new opportunities for citizens to engage with seagrass. The increasing use of online tools has created opportunities to collect and submit as well as help process and analyse data. Citizen science has helped researchers integrate scientific and local knowledge and engage communities to implement conservation measures. Here we use a selection of examples to demonstrate how citizen science can secure a future for seagrass.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons (PAH) in superficial water from a tropical estuarine system: Distribution, seasonal variations, sources and ecological risk assessment Texto completo
2018
Santos, Ewerton | Souza, Michel R.R. | Vilela Junior, Antônio R. | Soares, Laiane S. | Frena, Morgana | Alexandre, Marcelo R.
This study aimed to evaluate the PAH distribution, sources, seasonal variations and ecological risk assessment in superficial water from the Japaratuba River, Brazil. PAH concentrations ranged from 4 to 119ngL⁻¹. It was observed that the PAH total concentrations and profiles showed significant differences when comparing the dry season (summer) with the rainy season (winter). Furthermore, most of the PAH originated from pyrogenic sources in the winter, whereas a mixture of sources was observed in the summer. PAH concentration levels found in this study were considered lower than those obtained in other estuarine systems. Ecological risk assessment was determined for individual PAH, based on the risk quotient (RQ) to evaluate the risk of aquatic biota's exposure to PAH. Results suggested that the Japaratuba River has achieved a moderate degree of ecological risk for high molecular weight, showing the importance of identifying these carcinogenic and mutagenic compounds in aquatic systems.
Mostrar más [+] Menos [-]Spartina alterniflora δ15N as an indicator of estuarine nitrogen load and sources in Cape Cod estuaries Texto completo
2018
Kinney, Erin L. | Valiela, Ivan
δ15N values of coastal biota have been used as indicators of land-derived N-loads and sources to estuarine systems and should respond predictably to differences in nitrogen and be sensitive to changes in nitrogen, preferably at the low end of eutrophication. We evaluated Spartina alterniflora as an indicator species of N-loads and sources of δ15N throughout the growing season, and compared the average δ15N to estuarine nitrogen loads and sources for several estuaries receiving different watershed N-loads. δ15N of S. alterniflora differed among estuaries, and these differences were maintained even as δ15N declined during the end of the growing season. δ15N values increased with increasing nitrogen loads to the subestuaries and with increasing percent wastewater-derived nitrogen load. The response of δ15N of S. alterniflora to increased N loads was greater at low N-loads, and decreased as N-loads increased, suggesting that S. alterniflora is a good indicator of incipient nitrogen load.
Mostrar más [+] Menos [-]A zero percent plastic ingestion rate by silver hake (Merluccius bilinearis) from the south coast of Newfoundland, Canada Texto completo
2018
Liboiron, France | Ammendolia, Justine | Saturno, Jacquelyn | Melvin, Jess | Zahara, Alex | Richárd, Natalie | Liboiron, Max
Silver hake, (Merluccius bilinearis), contributes significant biomass to Northwest Atlantic ecosystems. The incidence of plastic ingestion for 134 individuals collected from Newfoundland, Canada was examined through visual examination of gastrointestinal contents and Raman spectrometry. We found a frequency of occurrence of ingestion of 0%. Through a comprehensive literature review of globally published fish ingestion studies, we found our value to be consistent with 41% (n = 100) of all reported fish ingestion rates. We could not statistically compare silver hake results to other species due to low sample sizes in other studies (less than n = 20) and a lack of standardized sampling methods. We recommend that further studies should 1) continue to report 0% plastic ingestion rates and 2) should describe location and species-specific traits that may contribute to 0% ingestion rates, particularly in locations where fish consumption has cultural and economic significance.
Mostrar más [+] Menos [-]Highly efficient oil-in-water emulsion and oil layer/water mixture separation based on durably superhydrophobic sponge prepared via a facile route Texto completo
2018
Wang, Jintao | Wang, Hongfei | Geng, Guihong
The fabrication of the materials with special wettability being capable of removing oil layer on water surface and oil droplets in oil-in-water emulsion is an important issue for water pollution. So far, it still remains challenging to explore a simple, facile, environmentally friendly approach for achieving this goal. Herein, inspired by the adhesion of marine mussels, the polydopamine (PDA) coating with hierarchical structure was directly fabricated onto the surface of melamine (MF) sponge by facile self-polymerization in dopamine solution. Then, a superhydrophobic and superoleophilic sponge was successfully obtained after the modification by dodecanethiol (DDT) at ambient temperature. The as-prepared sponge can selectively separate a series of oil droplets in oil-in-water emulsion with high efficiency (transparency: 76.6–93.8%) and absorb various oils or organic solvents up to 45.2–98.6 times of its own weight. Moreover, in conjunction with a vacuum system, great amounts of oils up to 20 times its own weight can be effectively separated from water surface within 1s by the sponge. Due to low cost, simple process, and easy accessibility, the as-prepared sponge has potential applications in oil-in-water emulsion separation and oil spill cleanup.
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