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Recent Advances in the Theory and Application of Nanofiltration: a Review Full text
2022
DU, Yuchen | Pramanik, Biplob Kumar | Zhang, Yang | Dumée, Ludovic | Jegatheesan, Veeriah
Water is the material basis for living organisms and one of the primary resources to maintain the sustainable development of the earth’s ecological environment. As a water purification method, nanofiltration (NF) separation technology has been widely considered by researchers in recent years. However, most of the studies on NF in the literature focus on membrane modification, and there are only a few reviews available. In this paper, the latest research progress of NF is reviewed, and the processes of NF membrane preparation using phase inversion, layer by layer, and interfacial polymerization are described. Polymer materials used for NF membrane preparation are reviewed and the main types of nanofillers to generate thin film nanocomposite membranes, including metal organic frameworks, boron nitride, Ti₃C₂TX, graphene oxide, SiO₂, and iron oxide are discussed. Membrane fouling is inevitable during NF operation and this paper analyzes the mechanisms of fouling and summarizes key pretreatment and cleaning methods required to remediate the long-term effects of cake layer formation. The steric hindrance effect, Donnan effect, and dielectric exclusion are analyzed, and some common characterization methods are summarized. The practical applications of NF are briefly introduced including groundwater, pharmaceutical wastewater, and textile wastewater treatment. Finally, the shortcomings and prospects of the existing research progress are put forward.
Show more [+] Less [-]Measuring speed of vessels operating around endangered southern resident killer whales (Orcinus orca) in Salish Sea critical habitat Full text
2022
Lo, Catherine F. | Nielsen, Kimberly A. | Ashe, Erin | Bain, David E. | Mendez-Bye, Andrea | Reiss, Stephanie A. | Bogaard, Laura T. | Collins, Marena Salerno | Williams, Rob
Motorized vessels are a major source of anthropogenic noise and can have adverse effects on species relying on sound for communication and feeding. Monitoring noise levels received by endangered southern resident killer whales (SRKWs) requires knowing the number, distance, and speed of surrounding vessels, including small boats that do not have Automatic Identification Systems (AIS). A method for estimating their speed is required to predict received noise levels and compliance with vessel regulations. We compared theodolite and photogrammetry methods to estimate the number, distance, and speed of vessels in SRKW Salish Sea summertime critical habitat. By treating AIS as “truth”, we found photogrammetry-derived ranges and speeds were more variable than theodolite estimates. Error in photogrammetry-derived speeds increased with range. Overall, we found time saved in the field using photogrammetry was more than offset by long analysis time. Theodolite data were relatively easy to collect, and produced accurate and precise results.
Show more [+] Less [-]Undesirable odour substances (geosmin and 2-methylisoborneol) in water environment: Sources, impacts and removal strategies Full text
2022
Abd El-Hack, Mohamed E. | El-Saadony, Mohamed T. | Elbestawy, Ahmed R. | Ellakany, Hany F. | Abaza, Samar S. | Geneedy, Amr M. | Salem, Heba M. | Taha, Ayman E. | Swelum, Ayman A. | Omer, Fatima A. | AbuQamar, Synan F. | El-Tarabily, Khaled A.
Off-flavours in fish products generated from recirculating aquaculture systems (RAS) are a major problem in the fish farming industry affecting the market demand and prices. A particular concern is the muddy or musty odour and taste in fish due to the presence of secondary metabolites geosmin and 2-methylisoborneol (2-MIB), produced by actinobacteria (mainly Streptomyces), myxobacteria and cyanobacteria. Off-flavours have deteriorated the quality of fish, rendering their products unfit for human consumption. The process of odour removal requires purification for several days to weeks in clean water; thus this leads to additional production costs. Geosmin and 2-MIB, detected at extremely low odour thresholds, are the most widespread off-flavour metabolites in aquaculture, entering through fish gills and accumulating in the fish adipose tissues. In this review, we aimed to determine the diversity and identity of geosmin- and 2-MIB-producing bacteria in aquaculture and provide possible strategies for their elimination.
Show more [+] Less [-]Mechanically durable green aerogel composite based on agricultural lignocellulosic residue for organic liquids/oil sorption Full text
2022
Chhajed, Monika | Verma, Chhavi | Sathawane, Manoj | Singh, Shiva | Maji, Pradip K.
Various oil spill cleanup sorbents have good hydrophobicity and oil separation efficiency, but their practical use has been limited due to the difficult and costly fabrication procedure. The research aims towards material development using the consumption of lignocellulosic agricultural residue for isolating cellulose nanofiber and its forward use to construct a 3D porous structure. A simple freeze-drying technique was used to assemble low-density porous structure. The biodegradable polylactic acid coating was used to alter the wettability from hydrophilic to hydrophobic and the maximum water contact angle value was around 120°. The prepared coated samples were testified for a series of oil/organic solvents-water mixtures. The sorption capacity was in the range of 28–70 g/g. The prepared aerogels were efficiently reused for at least 10 cycles. Developed material was used in continuous oil-water separation to remove oil from the water's surface. The cost analysis was estimated for scaleup production in the future.
Show more [+] Less [-]Distinct polymer-dependent sorption of persistent pollutants associated with Atlantic salmon farming to microplastics Full text
2022
Abihssira-García, Isabel S. | Kögel, Tanja | Gomiero, Alessio | Kristensen, Torstein | Krogstad, Morten | Olsvik, Pål A.
Interactions of microplastics and persistent organic pollutants (POPs) associated with Atlantic salmon farming were studied to assess the potential role of microplastics in relation to the environmental impact of aquaculture. HDPE, PP, PET and PVC microplastics placed for 3 months near fish farms sorbed POPs from aquafeeds. PET and PVC sorbed significantly higher levels of dioxins and PCBs compared to HDPE, while the levels sorbed to PP were intermediate and did not differ statistically from PET, PVC or HDPE. In addition, the composition of dioxins accumulated in caged blue mussels did not reflect the patterns observed on the microplastics, probably due to polymer-specific affinity of POPs. In conclusion, the results of this study show that microplastics occurring near fish farms can sorb aquafeed-associated POPs and, therefore, microplastics could potentially be vectors of such chemicals in the marine environment and increase the environmental impact of fish farming.
Show more [+] Less [-]Parachute science through a regional lens: Marine litter research in the Caribbean Small Island Developing States and the challenge of extra-regional research Full text
2022
Stöfen-O'Brien, Aleke | Ambrose, Kristal Kristene | Alleyne, Kristie S.T. | Lovell, Tricia Allison | Graham, Roxanne E.D.
The Wider Caribbean (WC) comprises numerous diverse developing states and territories including Small Island Developing States (SIDS). In particular, the Eastern part of the WC with its 16 SIDS receives a disproportionate amount of marine litter. Addressing this serious and urgent environmental problem requires scientific evidence to support and inform policy formation and decision making. Yet, as this study demonstrates, marine scientific research on the issue of marine litter in the Caribbean SIDS is predominantly undertaken by extra-regional scientists and organisations which might weaken the science-policy transfer to develop suitable and tailor-made solutions. The view point paper highlights issues and the problems associated with parachute science for the Caribbean SIDS before offering a series of potential policy-ready response options to address the identified challenges.
Show more [+] Less [-]Anthropogenic microfibres flux in an Antarctic coastal ecosystem: The tip of an iceberg? Full text
2022
Alurralde, Gastón | Isla, Enrique | Fuentes, Verónica | Olariaga, Alejandro | Maggioni, Tamara | Rimondino, Guido | Tatián, Marcos
Anthropogenic microfibres flux in an Antarctic coastal ecosystem: The tip of an iceberg? Full text
2022
Alurralde, Gastón | Isla, Enrique | Fuentes, Verónica | Olariaga, Alejandro | Maggioni, Tamara | Rimondino, Guido | Tatián, Marcos
This study describes the occurrence of anthropogenic microfibres (AMFs) found in sediment trap samples collected at 25 m water depth in an Antarctic fjord (Potter Cove, King George/25 de Mayo Island) from 2012 to 2015. During visual sorting of samples, AMFs were detected and described, and a subset was confirmed, via FTIR (Fourier transform infrared) spectroscopy, as semi-synthetic cellulosic and polyacrylonitrile polymers. Estimated flux of AMF varied from 115 to 152,750 microfibres m⁻² throughout the studied period, with sizes ranging from 10 to 450 μm in length. Maximum AMFs fluxes occurred in summer months. Sediment traps allowed detecting temporal patterns of small (μm) AMFs, usually undersampled with nets or sieves, providing a new insight into microplastic pollution in Antarctica and its relation to environmental conditions.
Show more [+] Less [-]Anthropogenic microfibres flux in an Antarctic coastal ecosystem: The tip of an iceberg? Full text
2022
Alurralde, Gastón | Isla, Enrique | Fuentes, Veronica | Olariaga, Alejandro | Maggioni, Tamara | Rimondino, Guido | Tatián, Marcos | Fondation Total | European Commission | Agencia Estatal de Investigación (España)
8 pages, 8 figures, 1 table | This study describes the occurrence of anthropogenic microfibres (AMFs) found in sediment trap samples collected at 25 m water depth in an Antarctic fjord (Potter Cove, King George/25 de Mayo Island) from 2012 to 2015. During visual sorting of samples, AMFs were detected and described, and a subset was confirmed, via FTIR (Fourier transform infrared) spectroscopy, as semi-synthetic cellulosic and polyacrylonitrile polymers. Estimated flux of AMF varied from 115 to 152,750 microfibres m−2 throughout the studied period, with sizes ranging from 10 to 450 μm in length. Maximum AMFs fluxes occurred in summer months. Sediment traps allowed detecting temporal patterns of small (μm) AMFs, usually undersampled with nets or sieves, providing a new insight into microplastic pollution in Antarctica and its relation to environmental conditions | The research was supported by the Total Foundation (ECLIPSE Project); Argentinean funds through PICT-Raíces 2011–1320 to IS, PICTO-DNA N° 119; the European Commission under the 7th Framework Programme through the Action – IMCONet (FP7 IRSES, action no. 319718) | With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S) | Peer reviewed
Show more [+] Less [-]Anthropogenic microfibres flux in an Antarctic coastal ecosystem: The tip of an iceberg? Full text
2022
Alurralde, Roque Gastón | Isla, Enrique | Fuentes, Verónica | Olariaga, Alejandro | Maggioni, Tamara | Rimondino, Guido Noé | Tatian, Marcos
This study describes the occurrence of anthropogenic microfibres (AMFs) found in sediment trap samples collected at 25 m water depth in an Antarctic fjord (Potter Cove, King George/25 de Mayo Island) from 2012 to 2015. During visual sorting of samples, AMFs were detected and described, and a subset was confirmed, via FTIR (Fourier transform infrared) spectroscopy, as semi-synthetic cellulosic and polyacrylonitrile polymers. Estimated flux of AMF varied from 115 to 152,750 microfibres m−2 throughout the studied period, with sizes ranging from 10 to 450 μm in length. Maximum AMFs fluxes occurred in summer months. Sediment traps allowed detecting temporal patterns of small (μm) AMFs, usually undersampled with nets or sieves, providing a new insight into microplastic pollution in Antarctica and its relation to environmental conditions. | Fil: Alurralde, Roque Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina | Fil: Isla, Enrique. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; España | Fil: Fuentes, Verónica. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; España | Fil: Olariaga, Alejandro. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias del Mar; España | Fil: Maggioni, Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina | Fil: Rimondino, Guido Noé. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina | Fil: Tatian, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina
Show more [+] Less [-]The waste collector: information from a pilot study on the interaction between the common octopus (Octopus vulgaris, Cuvier, 1797) and marine litter in bottom traps fishing and first evidence of plastic ingestion Full text
2022
Pedà, Cristina | Longo, Francesco | Berti, Claudio | Laface, Federica | De Domenico, Francesca | Consoli, Pierpaolo | Battaglia, Pietro | Greco, Silvestro | Romeo, Teresa
Few studies focused on behaviour adaptations of organisms to marine litter (ML) pollution in Mediterranean Sea. This research, investigates on some behavior traits of Octopus vulgaris, focusing on the interaction with ML during the artisanal fishing activities by the bottom traps in a small coastal area of the southern Tyrrhenian Sea. For the first time, this pilot study uses an integrated approach based on the Fishermen Ecological Knowledge as well as the analysis of ML found in the traps. First assessment of plastic ingestion in this species are also reported. Plastic and metal were the predominant ML categories observed into the bottom traps. A total of 62 plastics, mainly small microplastics and fibres shaped, were ingested. The ML finding in the bottom traps suggests an interesting behavior of the common octopus regarding its interaction with ML, in fact, it seems to bring ML inside its dens, as a collector.
Show more [+] Less [-]In-situ microplastic egestion efficiency of the eastern oyster Crassostrea virginica Full text
2022
Craig, Casey A. | Fox, David W. | Zhai, Lei | Walters, Linda J.
Microplastics (MP) are a pervasive environmental pollutant that enter coastal water bodies, posing an ingestion risk to marine biota. This study quantified the ability of the Eastern oyster (Crassostrea virginica) to egest MP in-situ in their biodeposits - feces and pseudofeces. Oysters of all sizes were able to egest environmental MP at a mean rate of 1 MP per 1 h through feces, and 1 MP per 2 h through pseudofeces. Smaller C. virginica were more efficient at egesting MP, and efficiency decreased by 0.8% per 1-g increase in tissue weight, with C. virginica of harvestable size being much less efficient. These findings are of relevance to resource managers for C. virginica populations as it further contributes to our understanding of MP accumulation in wild populations and has implications for not just C. virginica but also for their consumers.
Show more [+] Less [-]Functional trait responses of macrobenthic communities in seagrass microhabitats of a temperate lagoon Full text
2022
Hu, Chengye | Liu, Yongtian | Yang, Xiaolong | Shui, Bonian | Zhang, Xiumei | Wang, Jing
Understanding the effects of habitat heterogeneity on the functioning of macrobenthic communities is essential to the conservation of biodiversity in coastal ecosystems. However, the effects of habitat heterogeneity on the functional trait composition and diversity of seagrass bed macrobenthos are as scarce. In the present study, functional diversity indices (i.e., functional dispersion, functional richness, and Rao's quadratic entropy), RLQ analysis, and fourth-corner analysis indicated that macrobenthic functional trait composition and diversity differ among seagrass bed microhabitats (interior, edge, and bare sediment). More specifically, functional traits were more evenly distributed in the seagrass bed interior and edge habitats, when compared to bare sediment, and functional diversity was significantly higher (p < 0.01). Functional trait distributions were influenced by environmental parameters (e.g., total organic carbon, organic matter, and grain size). Suspension-feeding and burrowing bivalves preferentially inhabited bare sediment with high sand content and low TOC, whereas herbivorous, small, and sensitive species mainly inhabited muddy sediments with higher organic supply.
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