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Résultats 2061-2070 de 7,290
An integrated approach for sediment characterization of Dead Sea, Israel: Implications to marine environment Texte intégral
2022
Madakka, M. | Sreenivasulu, G. | Jayaraju, N. | Lakshmanna, B.
The Dead Sea (DS) sediment samples from two different sites on the west coast were analyzed. The objective is to document sediment characterization in order to study the interrelation existing among ingredients. The analyses show that Fe, Mg and Zn are the most significant trace elements found in the Sediment. Anthropogenic activities such as Industries, untreated sewage, agricultural wastes are some of the pollution sources that are considered to be lethal to the marine ecosystem. The DS is slowly disappearing at an alarming rate of 1 m/year. Hence a constant and precise mitigation, monitoring and management is mandatory. The present work is part of such goal in order to understand the health of the DS ecosystem. A cumulative and consistent effort of the Governments, stakeholders, tourists and the public will help in order to preserve and protect the health of the rare DS marine ecosystem for future generations.
Afficher plus [+] Moins [-]Risk assessment for seafood consumers exposed to mercury and other trace elements in fish from Long Island, New York, USA Texte intégral
2022
Ye, Xiayan | Lee, Cheng-Shiuan | Shipley, Oliver N. | Frisk, Michael G. | Fisher, Nicholas S.
We determined concentrations of Hg, Pb, Cd, Cr, As, Ni, Ag, Se, Cu, and Zn in muscle tissue of six commonly consumed Long Island fish species (black seabass, bluefish, striped bass, summer flounder, tautog, and weakfish, total sample size = 1211) caught off Long Island, New York in 2018 and 2019. Long-term consumption of these coastal fish could pose health risks largely due to Hg exposure; concentrations of the other trace elements were well below levels considered toxic for humans. By combining the measured Hg concentrations in the fish (means ranging from 0.11 to 0.27 mg/kg among the fish species), the average seafood consumption rate, and the current US EPA Hg reference dose (0.0001 mg/kg/d), it was concluded that seafood consumption should be limited to four fish meals per month for adults for some fish (bluefish, tautog) and half that for young children. Molar ratios of Hg:Se exceeded 1 for some black seabass, bluefish, tautog, and weakfish.
Afficher plus [+] Moins [-]Biomonitoring coastal pollution on the Arabian Gulf and the Gulf of Aden using macroalgae: A review Texte intégral
2022
Ameen, Fuad | Al-Homaidan, Ali A. | Almahasheer, Hanan | Dawoud, Turki | Alwakeel, Suaad | AlMaarofi, Sama
The transporting of oil via the Arabian Gulf for centuries has resulted in the pollution of the coasts by heavy metals, and therefore, remediation actions are needed. In this review, we first evaluated heavy metal pollution on the coasts by assembling the research on published metal concentrations in sediments and water bodies surrounding the Arabian Peninsula. Research revealed uneven pollution of heavy metals, meaning that before remediation, the most polluted sites should be found. This could be done most conveniently using biomonitoring. The Arabian Peninsula is a unique ecoregion due to the extremely high temperature in summer, and therefore, it needs its specific standardization procedure for biomonitoring. To get an overview of the current information on biomonitoring, we gathered a dataset of 306 published macroalgal observations from the Arabian Gulf and the Gulf of Aden. The heavy metal concentration dataset of macroalgae was analyzed with a multivariate principal component analysis. As a result of the published works elsewhere and our data analysis, we recommend that green Ulva and brown Padina species are used in the biomonitoring of heavy metal pollution on the Arabian Peninsula's eastern and southern coasts. However, more species might be needed if these species do not occur at the site. The species incidence should first be monitored systematically in each area, and common species should be used. The species used should be chosen locally and sampled at the same depth at low tide in spring or early summer, from February to May, before the hottest season. The composite samples of different apical sections of the thallus should be collected. The standardization of the monitoring processes benefits future remediation actions.
Afficher plus [+] Moins [-]Assessing the potential for invasive species introductions and secondary spread using vessel movements in maritime ports Texte intégral
2022
Costello, Katie E. | Lynch, Sharon A. | McAllen, Rob | O'Riordan, Ruth M. | Culloty, Sarah C.
Global shipping facilitates the introduction of invasive species and parasites via ballast water and hull fouling. Regional management of invasives may be strengthened by identifying the major routes in a network, to allow for targeted ship inspections. This study used cargo shipping records to establish the connectivity of shipping routes between ports in Ireland and other nations. 9291 records were analysed, investigating vessel residence and journey times. On average, vessels spent up to five days in port and less than five days at sea. However, there was strong variation, with general cargo ships recording up to 13 days in port. A horizon scan for species likely to invade in Ireland was incorporated for five species and their associated parasites: American razor clam, Asian shore crab, Brush clawed shore crab, Chinese mitten crab and American slipper limpet. Routes of concern are highlighted and a general framework for effective management is outlined.
Afficher plus [+] Moins [-]Deposition rates and residence time of litter varies among beaches in the Lofoten archipelago, Norway Texte intégral
2022
Solbakken, V.S. | Kleiven, S. | Haarr, M.L.
A considerable portion of marine litter pollutes the world's coastlines. Its accumulation on beaches represents the product of deposition and retention, processes which are not well understood. A mark-recapture study was performed with a two-week sampling interval at three sites in Lofoten, Norway. Deposition and retention vary over relatively small spatial scales (approx. 13 km radius). No correlation was found among sites in the timing of high and low deposition events, suggesting these are governed by local factors. Contrastingly, the correlation in the timing of high and low retention events was generally stronger among sites, suggesting these may be affected by regional factors. The results underline the importance of customising cleanup frequency for different beaches as spatiotemporal variation in the relative importance of deposition and retention dictate the optimal frequency for maximal removal of litter from circulation in the local marine environment, which cannot be discerned from accumulation (i.e., standing stock) alone.
Afficher plus [+] Moins [-]Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texte intégral
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-Préfol, Mathilde | Gorsky, Gabriel | Galgani, François | Bruzaud, Stéphane | Pedrotti, Maria Luiza
Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texte intégral
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-Préfol, Mathilde | Gorsky, Gabriel | Galgani, François | Bruzaud, Stéphane | Pedrotti, Maria Luiza
The Mediterranean Sea is one of the most studied regions in the world in terms of microplastic (MP) contamination. However, only a few studies have analysed the chemical composition of MPs at the Mediterranean Sea surface. In this context, this study aims to describe the chemical composition as a function of particle size, mass and number concentrations of MPs collected in the surface waters of the Mediterranean Sea. The chemical composition showed a certain homogeneity at the Mediterranean Sea scale. The main polymers identified by Fourier Transform Infra-Red (FTIR) spectroscopy were poly(ethylene) (67.3 ± 2.4%), poly(propylene) (20.8 ± 2.1%) and poly(styrene) (3.0 ± 0.9%). Nevertheless, discrepancies, confirmed by the literature, were observed at a mesoscale level. Thus, in the North Tyrrhenian Sea, the proportion of poly(ethylene) was significantly lower than the average value of the Mediterranean Sea (57.9 ± 10.5%). Anthropic sources, rivers, or polymer ageing are assumed to be responsible for the variations observed.
Afficher plus [+] Moins [-]Chemical composition of microplastics floating on the surface of the Mediterranean Sea Texte intégral
2022
Kedzierski, Mikaël | Palazot, Maialen | Soccalingame, Lata | Falcou-préfol, Mathilde | Gorsky, Gabriel | Galgani, Francois | Bruzaud, Stéphane | Pedrotti, Maria Luiza
The Mediterranean Sea is one of the most studied regions in the world in terms of microplastic (MP) contamination. However, only a few studies have analysed the chemical composition of MPs at the Mediterranean Sea surface. In this context, this study aims to describe the chemical composition as a function of particle size, mass and number concentrations of MPs collected in the surface waters of the Mediterranean Sea. The chemical composition showed a certain homogeneity at the Mediterranean Sea scale. The main polymers identified by Fourier Transform Infra-Red (FTIR) spectroscopy were poly(ethylene) (67.3 ± 2.4%), poly(propylene) (20.8 ± 2.1%) and poly(styrene) (3.0 ± 0.9%). Nevertheless, discrepancies, confirmed by the literature, were observed at a mesoscale level. Thus, in the North Tyrrhenian Sea, the proportion of poly(ethylene) was significantly lower than the average value of the Mediterranean Sea (57.9 ± 10.5%). Anthropic sources, rivers, or polymer ageing are assumed to be responsible for the variations observed.
Afficher plus [+] Moins [-]Structural factors driving benthic invertebrate community structure on historical shipwrecks in a large North Atlantic marine sanctuary Texte intégral
2022
Meyer-Kaiser, Kirstin S. | Mires, Calvin H. | Kovacs, Maryann | Kovacs, Evan | Haskell, Benjamin
Shipwrecks are irreplaceable historical resources and valuable biological habitats. Understanding the environmental and anthropogenic factors affecting shipwrecks is critical for preservation in situ. We used remotely operated vehicles to study the benthic invertebrate communities on four shipwrecks in Stellwagen Bank National Marine Sanctuary (SBNMS, North Atlantic, USA). Shipwrecks included coal schooners and a passenger steamer, all >100 years old. These large, complex structures hosted dense populations of invertebrates (34 species), especially on high-relief and overhanging substrata. Some species that are otherwise rare in the community may proliferate through asexual reproduction and form dense populations on shipwrecks. We also investigated impacts of entangled fishing gear on the invertebrate communities on each shipwreck and found that areas with the most ghost gear have lower species richness and different community structure. Fishing, particularly bottom trawling, damages shipwrecks and poses a threat to these valuable cultural resources and biological habitats in SBNMS.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons (PAHs) in fishery resources affected by the 2019 oil spill in Brazil: Short-term environmental health and seafood safety Texte intégral
2022
Magalhães, Karine Matos | Carreira, Renato Silva | Rosa Filho, José Souto | Rocha, Pedro Palmeira | Santana, Francisco Marcante | Yogui, Gilvan Takeshi
We present herein a short-term impact on marketed fisheries and human health safety in the first three months following the 2019 oil spill in Brazil. Total PAHs in the edible tissues of 34 finfish and shellfish species ranged from 8.71 to 418 ng g⁻¹ wet weight, with robust evidence supporting crude oil contamination. A prevalence of low molecular weight PAHs was observed, mainly naphthalenes. A decreasing trend in mean total PAHs from mollusks (134 ng g⁻¹) to crustaceans (73.9 ng g⁻¹) and to fishes (45.3 ng g⁻¹) was noted. The spilled oil caused immediate negative impacts on the local seafood market, despite less than 3% of samples exhibited concentrations above levels of concern, revealing a low probability for human health risks. These findings demonstrate that governments must be prepared to provide not only science-based quick responses but also effective science communication for society upon environmental disasters.
Afficher plus [+] Moins [-]Microplastics distribution in bottom sediments of the Baltic Sea Proper Texte intégral
2022
Chubarenko, Irina | Esiukova, Elena | Zobkov, Mikhail | Isachenko, Igor
An abundance of microplastics particles (0.2–5 mm, MPs) in bottom sediments is analyzed based on 53 samples (3 to 215 m deep) obtained in 8 cruises of research vessels across the Baltic Sea Proper in March–October 2015–2016. MPs content varied between stations from 103 up to 10,179 items kg⁻¹ d.w., with the bulk mean of 863 ± 1371 items kg⁻¹ d.w., showing a statistically significant increase with water depth. As many as 74.5% of MPs are of fibrous shape, followed by films (19.8%) and fragments (5.7%). The distributions of fibres, fragments, films, and different types of natural bottom sediments are significantly different, highlighting the specific behaviour of each of these kinds of bottom deposits. A statistically significant correlation between water depth and fibres content is found. Based on the analysis of oceanographic factors and sedimentological principles, an erosion/transition/accumulation pattern for fibres in the Baltic Sea Proper is outlined. Fibres can be considered as a specific type of “synthetic sediment”, while principles of distribution of other MPs are not yet certain.
Afficher plus [+] Moins [-]Using beached bird data to assess seabird oiling susceptibility Texte intégral
2022
Waugh, Jazzmine K. | Jones, Timothy | Parrish, Julia K.
Oil spills can cause severe impacts on seabirds, the extent of which varies by species. We investigated taxon-specific susceptibility using data from the Nestucca and Tenyo Maru oil spills in the northeast Pacific together with seasonally and spatially overlapping baseline beached bird abundance data collected over a 17-year time-period. Multivariate analyses revealed patterns of variation between spill and non-spill data, primarily driven by differences in the relative abundance of common murres (Uria aalge) and northern fulmars (Fulmarus glacialis). In subsequent susceptibility analyses, alcid (Alcidae spp.) carcasses were generally overrepresented in spill data, while gulls (Larus spp.), tubenoses (Procellariformes spp.), and cormorants (Phalacrocoracidae spp.) were generally under-represented. We found that the baseline data had high variability, suggesting a need for many years of baseline data. We propose that where appropriate baseline data exists, this method can be employed to investigate the seabirds most vulnerable to oiling.
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