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Zooplankton distribution and influencing factors in the South Yellow Sea in spring Texte intégral
2019
Wang, Xiao | Xu, Qinzeng | Jiang, Meijie | Liu, Ping | Wang, Zongling
Zooplankton were studied in the largest scale investigation in the South Yellow Sea in spring 2007 by using large plankton net when the green tide hasn't yet occurred. Ninety-six zooplankton species were identified. Copepods, pelagic larvae and hydromedusae were comprised of the largest number of species; Calanus sinicus, Paracalanus parvus, Aidanosagitta crassa, Euphausiidae larvae, Oithona plumifera and Corycaeus affinis were dominant species and their abundance comprised 81.65% of total abundance. Three high abundance areas contained with an average of 224.31 ± 247.93 individual/m³, with an average total biomass of 674.33 ± 1696.92 mg/m³; The average of Shannon-Wiener diversity, Pielou evenness and Margalef richness was 1.96 ± 0.61, 0.50 ± 0.14 and 2.31 ± 0.95, respectively. The Shannon-Wiener diversity and Pielou evenness showed positive correlation with bottom temperature, while Shannon-Wiener diversity and Margalef richness were positively correlated with bottom salinity. Additionally, Pielou evenness and Margalef richness showed negative correlation with total abundance which indicated that sampling efforts might affect the findings.
Afficher plus [+] Moins [-]Assessment of seabed litter in the Northern and Central Adriatic Sea (Mediterranean) over six years Texte intégral
2019
Strafella, P. | Fabi, G. | Despalatovic, M. | Cvitković, I. | Fortibuoni, T. | Gomiero, A. | Guicciardi, S. | Marceta, B. | Raicevich, S. | Tassetti, A.N. | Spagnolo, A. | Scarcella, G.
Seabed debris is much less investigated in respect to the sea surface and shores due to sampling difficulties and costs. However, detecting marine benthic litter is fundamental for developing policies aimed at achieving the Good Environmental Status in European Seas by 2020, as requested by the Marine Strategy Framework Directive.This study estimates seafloor litter abundance, composition, spatial distribution and main sources in the North-Central Adriatic Sea (FAO GSA 17) over a six-year period (2011–2016) with 67 stations sampled per year, representing the longest data set for the basin. Litter items collected using a “rapido” trawl were classified in six major categories.The average density of the litter collected over six years was 102.66 ± 41.91 kg/km2. The highest concentration of litter was found in stations close to the coast within 30 m depth with a mean weight of 142.90 ± 27.20 kg/km2, while the lowest value was recorded between 30 and 50 m of depth (41.12 ± 9.62 kg/km2). Plastic was dominant followed by metal and other litter materials. Lost fishing nets and mussel culture debris accounted for 50% of the overall plastic litter collected. These data and the systematic monitoring of marine litter provide useful information to implement necessary measures to manage marine litter and minimize this type of anthropogenic pollution in the Adriatic region.
Afficher plus [+] Moins [-]Identification, recovery, and impact of ghost fishing gear in the Mullica River-Great Bay Estuary (New Jersey, USA): Stakeholder-driven restoration for smaller-scale systems Texte intégral
2019
Sullivan, Mark | Evert, Steven | Straub, Peter | Reding, Melanie | Robinson, Nathan | Zimmermann, Elizabeth | Ambrose, David
The impact of ghost fishing in large coastal ecosystems has generated considerable interest. In smaller, understudied systems with fewer stakeholders, derelict fishing gear (DFGs) may have impacts similar to these larger systems at the same relative scale. Four years of side scan sonar surveys in the Mullica River-Great Bay Estuary (New Jersey, USA) supported the recovery of 1776 DFGs off-season by commercial partners. Locations with high densities of recovered DFGs (>200 DFGs/km²) occupied intersections of recreational vessel traffic and commercial crabbing activity. Condition and depth-in-sediment of recovered DFGs was used to evaluate true bycatch (terrapins, whelks, blue crabs) versus species utilizing degraded gear as habitat (juvenile tautog, oyster toadfish). Critically, gear recovered in-season with low cost sonars (an additional 225 DFGs) prevented the accumulation of new DFGs which likely generate the highest percentages of bycatch. Removal of DFGs in this system led to significant ecological (reduced bycatch), economic (>$61,000 in direct pay, reused gear), and anticipated future benefits (increased harvest).
Afficher plus [+] Moins [-]Debris ingestion by carnivorous consumers: Does the position in the water column truly matter? Texte intégral
2019
Di Beneditto, Ana Paula Madeira | Oliveira, Ariane da Silva
The hypothesis that carnivorous consumers associated with the seabed are more likely to ingest marine debris was tested based on stomach content analysis of fish (Trichiurus lepturus and species of Ariidae) and cetaceans (Sotalia guianensis and Pontoporia blainvillei). Among 596 stomach contents, only 22 (3.7%) contained debris. The debris was flexible plastic, nylon yard, paper, latex, styrofoam and cigarette filter. The proportion of stomach contents with debris varied among species: P. blainvillei (pelagic demersal consumer) presented the highest frequency of ingestion (15.7%), while T. lepturus (pelagic consumer), S. guianensis (pelagic consumer) and Ariidae (demersal consumer) presented similar frequencies (1.3–1.8%). Therefore, a feeding site in the water column does not predict the probability of debris ingestion. Concerning these species, this probability seems to be more associated with prey-capture strategies (or feeding behavior), regardless of debris availability in the environment.
Afficher plus [+] Moins [-]Is this your glitter? An overlooked but potentially environmentally-valuable microplastic Texte intégral
2019
Tagg, Alexander S. | Ivar do Sul, Juliana A.
As microplastic pollution evolved to a well-established research field, microplastic scientists started to explore new avenues in the field. Yet, while a multitude of different types of microplastics (microbeads, fibres, fragments) have been well-documented in microplastic literature, our analysis of this literature shows that glitter particles have been overlooked by the field. However, due to the presence of glitter-based research in forensic science, we explore the idea that glitter may have the potential to act as “flag items” - or markers – of a likely source, due to the often complex and individual composition of glitter particles compared to traditional microplastics, such as microbeads. As such, this article demonstrates glitter has insofar been overlooked as a microplastic particle, and demonstrates that glitter may have an important role in explaining microplastic pollution dynamics from source to sink.
Afficher plus [+] Moins [-]Trace metals and persistent organic pollutants fingerprint on the particle flux in the deep subtropical NE Atlantic Texte intégral
2019
Stern, J. | Kaiser, D. | Przibilla, A. | Schulz-Bull, D.E. | Waniek, J.J.
Particle flux material collected in 2000 m depth in the Northeast Atlantic at 33°N and 22°W was analyzed for trace metals and persistent organic pollutants. Element enrichment factors relative to lithogenic Al were elevated indicating possible anthropogenic contributions for all trace metals except V. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls and the pesticide DDT exhibited median fluxes of 10.40 μg m⁻²d⁻¹,0.29 μg m⁻² d⁻¹, and 0.90 μg m⁻² d⁻¹, respectively. Flux composition reflected long range transport, with low molecular weight and low-chlorinated compounds dominating ∑₁₅PAH and ∑₂₃PCB. PAH isomer ratios identified fossil fuel combustion as the main ∑₁₅PAH source. The composition of ∑₄DDT suggested inputs of the fresh technical pesticide during high dust intensity periods. Pollutant fluxes showed seasonality linked to export production in the region, as well as a dependence on annual and sub-annual dust input events.
Afficher plus [+] Moins [-]Microplastic pollution in the sediments of Sidi Mansour Harbor in Southeast Tunisia Texte intégral
2019
Chouchene, Khawla | da Costa, João Pinto | Wali, A. | Girão, Ana V. | Hentati, Olfa | Duarte, Armando C. | Rocha-Santos, Teresa | Ksibi, Mohamed
Despite the increasing interest in microplastic (MP) research, the accurate prevalence, distribution and fate of these materials in the environment is yet poorly known and, consequently, a focus of debate. Hence, to better ascertain the presence of microplastics in specific environments, samples from 35 random sites distributed across a 4200-meter long section from the area of Sidi Mansour, Sfax-Tunisia, were collected and analyzed. MPs were extracted, digested with potassium hydroxide and dyed with Eosin B, for visual microscopy counting and sorting. Polymer composition and surface morphology were identified by FTIR-ATR spectroscopy and SEM microscopy. Total abundances ranged from 252 to-5332 particles per m² where fragments and granules were the most frequent types of microplastics. These findings highlight the considerable presence of these materials in the studied harbor region and underscore the density dependence on the distribution and occurrence of MPs and how these tend to accumulate in the sandy sediments.
Afficher plus [+] Moins [-]Sterol biomarkers and fecal coliforms in a tropical estuary: Seasonal distribution and sources Texte intégral
2019
Frena, Morgana | Santos, Ana Paula Stein | Souza, Michel R.R. | Carvalho, Shalana Santos | Madureira, Luiz A.S. | Alexandre, Marcelo R.
The Sergipe River estuary has been subjected to a range of anthropogenic activities including food, plastic, textile, ceramic and metallurgical production plants along with domestic sewage inputs, all of which are of environmental concern. In this study, the levels of fecal coliforms (FC) in surface water samples and sterols in superficial sediment samples collected from the Sergipe River estuary were determined. Based on the FC concentrations, 58% of the water samples were considered Water Potentially Unusable (WPU) according to the United States Environmental Protection Agency (USEPA). Concentrations of coprostanol ranged from 13 to 1072 ng g−1, indicating a significant input of sewage at some points in the estuary. Principal Component Analysis (PCA) showed that there is no clear correlation between the coprostanol and coliform data, which may be due to the high resistance to degradation of coprostanol in sediments and to recent inputs of sewage at the water sample collection points.
Afficher plus [+] Moins [-]Efficiency in the environmental management of plastic wastes at Brazilian ports based on data envelopment analysis Texte intégral
2019
Gobbi, Clarice Neffa | Sanches, Vânia Maria Lourenço | Guimarães, Maria José de Oliveira Cavalcanti | Freitas, Marcos Aurélio Vasconcelos de | Pacheco, Elen Beatriz Acordi Vasques
The aim of this study was to analyze different port areas (leased, nonleased and vessels) in terms of plastic segregation (scenario 1) and how much of this plastic is recycled (scenario 2). Data envelopment analysis was applied and the variables were total amount of solid waste and percentage of segregated plastic in relation to total solid waste (scenario 1) and amount of segregated plastics and percentage of recycled in relation to segregated plastics (scenario 2). Segregation efficiency was low (49%) in the nonleased area, but all the segregated material is recycled, suggesting that the management bottleneck in this case is waste segregation. Similar segregation results were obtained in the leased areas and vessels (36 and 35%, respectively), but recycling efficiency was greater in the former (92 and 24%, respectively).
Afficher plus [+] Moins [-]Distribution and impacts of microplastic incorporation within sea ice Texte intégral
2019
Geilfus, N.-X. | Munson, K.M. | Sousa, J. | Germanov, Y. | Bhugaloo, S. | Babb, D. | Wang, F.
Microplastics (plastic particles <5 mm) are an emerging concern in Arctic sea ice with measured concentrations orders of magnitude higher than in surface seawater. However, incorporation of microplastics into sea ice, and their impact on sea ice properties, is unknown. We added microplastic particles in a microcosm experiment to determine microplastic distributions and effects on sea ice properties. Microplastic additions did not affect sea ice growth, but high concentrations of microplastics at the ice surface resulted in high ice salinity and changes in sea ice albedo. Field studies in the Gulf of Bothnia (Baltic Sea) showed sea ice concentration of microplastics from 8 to 41 particles per liter of melted ice, wich were much lower than those found to impact sea ice properties in the microcosm experiments. However, should microplastic concentrations increase, microplastic incorporation in sea ice may impact sea ice albedo.
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