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Profiling of Polycyclic Aromatic Hydrocarbons and Diagnostic Ratios of Kpite Oil Spill Impacted Site in Rivers State, Nigeria Texte intégral
2021
Onojake, M. C. | Eromosele, G. O. | Osuji, Leo C.
Polycyclic Aromatic Hydrocarbon profile of Kpite oil spill impacted site in Rivers state, Nigeria was evaluated to determine the level of contamination of the soil. Four composite oil impacted soil samples were collected at different depths; surface (0-15cm) and subsurface (15-30cm) after a field reconnaissance. Extraction of the oil was carried out on the soil samples and the Polycyclic Aromatic Hydrocarbons were quantified using the Gas Chromatography- flame ionization detector. Results showed that Naphthalene was the most abundant in the range of 0.25 to 1.49 mg kg-1. Fluoranthene followed closely with concentrations in the range of 0.01 to 1.28 mg kg-1. PAHs like Benzo (k) fluoranthene, Benzo (e) pyrene, Dibenzo (a, h)anthracene, Indeno (1, 2, 3-cd) pyrene and Benzo (g, h, i) showed low concentrations of less than 0.01 indicating that strong weathering had occurred. The diagnostic ratios such as Phenanthrene/Anthracene (Phen/Anth), Benzo (a) anthracene Chrysene ((BaA)/Chry) and Fluoranthene/Pyrene (Flth/Py) and sum of chrysene/Phenanthrene ΣChry/ΣPhen were calculated and used to unravel the source of hydrocarbons. Results showed ratios of Flth/Py >1.0 and Phen/Anth ranges from 1.19 to 2.03 (< 10) which denote contamination sources, implying that the hydrocarbon sources are not just petrogenic but rather may due to contamination sources of combustion processes or the area was exposed to bush burning.
Afficher plus [+] Moins [-]Charges critiques pour la vegetation.
1993
Thimonier A. | Dupouey J.L.
Les modifications chimiques de l' atmosphere et leurs effets sur l' environnement.
1988
Megie G.
Fluxes of Cu, Zn, Pb, Cd, Cr, and Ni in temperate forest ecosystems. A literature review.
1989
Bergkvist B. | Folkeson L. | Berggren D.
Trace elements in the hydrologic cycle of a tolerant hardwood forest ecosystem.
1986
Foster N.W. | Nicolson J.A.
Silver fir decline in the Vosges mountains (France): role of climate and silviculture.
1989
Becker M. | Landmann G. | Levy G.
Anthropogenic microfibers are highly abundant at the Burdwood Bank seamount, a protected sub-Antarctic environment in the Southwestern Atlantic Ocean Texte intégral
2022
Di Mauro, Rosana | Castillo, Santiago | Pérez, Analía | Iachetti, Clara M. | Silva, Leonel | Tomba, Juan P. | Chiesa, Ignacio L.
Anthropogenic microfibers are highly abundant at the Burdwood Bank seamount, a protected sub-Antarctic environment in the Southwestern Atlantic Ocean Texte intégral
2022
Di Mauro, Rosana | Castillo, Santiago | Pérez, Analía | Iachetti, Clara M. | Silva, Leonel | Tomba, Juan P. | Chiesa, Ignacio L.
Microplastics debris in the marine environment have been widely studied across the globe. Within these particles, the most abundant and prevalent type in the oceans are anthropogenic microfibers (MFs), although they have been historically overlooked mostly due to methodological constraints. MFs are currently considered omnipresent in natural environments, however, contrary to the Northern Hemisphere, data on their abundance and distribution in Southern Oceans ecosystems are still scarce, in particular for sub-Antarctic regions. Using Niskin bottles we've explored microfibers abundance and distribution in the water column (3–2450 m depth) at the Burdwood Bank (BB), a seamount located at the southern extreme of the Patagonian shelf, in the Southwestern Atlantic Ocean. The MFs detected from filtered water samples were photographed and measured using ImageJ software, to estimate length, width, and the projected surface area of each particle. Our results indicate that small pieces of fibers are widespread in the water column at the BB (mean of 17.4 ± 12.6 MFs.L⁻¹), from which, 10.6 ± 5.3 MFs.L⁻¹ were at the surface (3–10 m depth), 20 ± 9 MFs.L⁻¹ in intermediate waters (41–97 m), 24.6 ± 17.3 MFs.L⁻¹ in deeper waters (102–164 m), and 9.2 ± 5.3 MFs.L⁻¹ within the slope break of the seamount. Approximately 76.1% of the MFs were composed of Polyethylene terephthalate, and the abundance was dominated by the size fraction from 0.1 to 0.3 mm of length. Given the high relative abundance of small and aged MFs, and the oceanographic complexity of the study area, we postulate that MFs are most likely transported to the BB via the Antarctic Circumpolar Current. Our findings imply that this sub-Antarctic protected ecosystem is highly exposed to microplastic pollution, and this threat could be spreading towards the highly productive waters, north of the study area.
Afficher plus [+] Moins [-]Anthropogenic microfibers are highly abundant at the Burdwood Bank seamount, a protected sub-Antarctic environment in the Southwestern Atlantic Ocean Texte intégral
2022
Di Mauro, Rosana Patricia | Castillo, Santiago | Pérez, Analía Fernanda | Iachetti, Clara Margarita | Silva, Leonel Ignacio | Tomba, Juan Pablo | Chiesa, Ignacio Luis
Microplastics debris in the marine environment have been widely studied across the globe. Within these particles, the most abundant and prevalent type in the oceans are anthropogenic microfibers (MFs), although they have been historically overlooked mostly due to methodological constraints. MFs are currently considered omnipresent in natural environments, however, contrary to the Northern Hemisphere, data on their abundance and distribution in Southern Oceans ecosystems are still scarce, in particular for sub-Antarctic regions. Using Niskin bottles we've explored microfibers abundance and distribution in the water column (3–2450 m depth) at the Burdwood Bank (BB), a seamount located at the southern extreme of the Patagonian shelf, in the Southwestern Atlantic Ocean. The MFs detected from filtered water samples were photographed and measured using ImageJ software, to estimate length, width, and the projected surface area of each particle. Our results indicate that small pieces of fibers are widespread in the water column at the BB (mean of 17.4 ± 12.6 MFs.L−1), from which, 10.6 ± 5.3 MFs.L−1 were at the surface (3–10 m depth), 20 ± 9 MFs.L−1 in intermediate waters (41–97 m), 24.6 ± 17.3 MFs.L−1 in deeper waters (102–164 m), and 9.2 ± 5.3 MFs.L−1 within the slope break of the seamount. Approximately 76.1% of the MFs were composed of Polyethylene terephthalate, and the abundance was dominated by the size fraction from 0.1 to 0.3 mm of length. Given the high relative abundance of small and aged MFs, and the oceanographic complexity of the study area, we postulate that MFs are most likely transported to the BB via the Antarctic Circumpolar Current. Our findings imply that this sub-Antarctic protected ecosystem is highly exposed to microplastic pollution, and this threat could be spreading towards the highly productive waters, north of the study area. | Fil: Di Mauro, Rosana Patricia. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Castillo, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina | Fil: Pérez, Analía Fernanda. Universidad Maimónides; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Iachetti, Clara Margarita. Universidad Nacional de Tierra del Fuego; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Silva, Leonel Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina | Fil: Tomba, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina | Fil: Chiesa, Ignacio Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina
Afficher plus [+] Moins [-]A catastrophic change in a european protected wetland: From harmful phytoplankton blooms to fish and bird kill Texte intégral
2022
Demertzioglou, Maria | Genitsaris, Savvas | Mazaris, Antonios D. | Kyparissis, Aris | Voutsa, Dimitra | Kozari, Argyri | Kormas, Konstantinos Ar | Stefanidou, Natassa | Katsiapi, Matina | Michaloudi, Evangelia | Moustaka-Gouni, Maria
Understanding the processes that underlay an ecological disaster represents a major scientific challenge. Here, we investigated phytoplankton and zooplankton community changes before and during a fauna mass kill in a European protected wetland. Evidence on gradual development and collapse of harmful phytoplankton blooms, allowed us to delineate the biotic and abiotic interactions that led to this ecological disaster. Before the mass fauna kill, mixed blooms of known harmful cyanobacteria and the killer alga Prymnesium parvum altered biomass flow and minimized zooplankton resource use efficiency. These blooms collapsed under high nutrient concentrations and inhibitory ammonia levels, with low phytoplankton biomass leading to a dramatic drop in photosynthetic oxygenation and a shift to a heterotrophic ecosystem phase. Along with the phytoplankton collapse, extremely high numbers of red planktonic crustaceans-Daphnia magna, visible through satellite images, indicated low oxygen conditions as well as a decrease or absence of fish predation pressure. Our findings provide clear evidence that the mass episode of fish and birds kill resulted through severe changes in phytoplankton and zooplankton dynamics, and the alternation on key abiotic conditions. Our study highlights that plankton-related ecosystem functions mirror the accumulated heavy anthropogenic impacts on freshwaters and could reflect a failure in conservation and restoration measures.
Afficher plus [+] Moins [-]Comprehensive assessment of nitrous oxide emissions and mitigation potentials across European peatlands Texte intégral
2022
Lin, Fei | Zuo, Hongchao | Ma, Xiaohong | Ma, Lei
European natural peatlands have undergone long-term anthropogenic drainage activities that have severely decreased their functions, such as carbon sequestration. Recent rewetting has been conducted to restore the ecosystem services of peatlands and mitigate the emissions of potent greenhouse gases such as nitrous oxide (N₂O). However, the magnitudes and spatial patterns of annual N₂O fluxes and their mitigation potentials across European peatlands remain unknown. Here, we synthesized 492 annual N₂O flux data points from 77 in situ studies across European peatlands and found that the soil annual N₂O fluxes varied extensively from −1.08 to 33.40 kg N₂O–N ha⁻¹ yr⁻¹; these results were significantly and interactively (P < 0.05) affected by the peatland status, climatic regime and nutrient supply type. Drainage significantly (P < 0.05) stimulated soil N₂O emissions from natural minerotrophic rather than ombrotrophic peatlands, regardless of the climatic regime. Similarly, rewetting significantly (P < 0.05) reduced soil N₂O emissions from drained minerotrophic rather than ombrotrophic peatlands, demonstrating that the high N₂O emissions were driven by a simultaneous decline in the water table depth and increase in the soil nitrogen (N) availability. Magnitudes of the increases or decreases in N₂O emissions due to drainage or rewetting were also significantly influenced by the land-use and drainage history before rewetting and in the years following drainage/rewetting, respectively. The estimated annual mean N₂O emission total was found to be 90.42 (95% confidence interval: 64.49–122.57) Gg N₂O–N in 2020 from European peatlands. Scenario analysis showed that drained peatlands should be rewetted expeditiously; postponing rewetting would cause larger emissions from continued N₂O emissions from drained peatlands. Fully rewetting the drained peatlands used for forestry and peat extraction and partially rewetting those used for agriculture and grassland comprise a strategy for mitigating drained peatland N₂O emissions without compromising food security.
Afficher plus [+] Moins [-]Experimental assessment of salinization effects on freshwater zooplankton communities and their trophic interactions under eutrophic conditions Texte intégral
2022
Ersoy, Zeynep | Abril, Meritxell | Cañedo-Argüelles, Miguel | Espinosa, Carmen Gertrudis | Vendrell-Puigmitja, Lidia | Proia, Lorenzo
Experimental assessment of salinization effects on freshwater zooplankton communities and their trophic interactions under eutrophic conditions Texte intégral
2022
Ersoy, Zeynep | Abril, Meritxell | Cañedo-Argüelles, Miguel | Espinosa, Carmen Gertrudis | Vendrell-Puigmitja, Lidia | Proia, Lorenzo
Freshwater ecosystems are becoming saltier due to human activities. The effects of increased salinity can lead to cascading trophic interactions, affecting ecosystem functioning and energy transfer, through changes in community and size structure. These effects can be modulated by other environmental factors, such as nutrients. For example, communities developed under eutrophic conditions could be less sensitive to salinization due to cross-tolerance mechanisms. In this study, we used a mesocosm approach to assess the effects of a salinization gradient on the zooplankton community composition and size structure under eutrophic conditions and the cascading effects on algal communities. Our results showed that zooplankton biomass, size diversity and mean body size decreased with increased chloride concentration induced by salt addition. This change in the zooplankton community did not have cascading effects on phytoplankton. The phytoplankton biomass decreased after the chloride concentration threshold of 500 mg L⁻¹ was reached, most likely due to direct toxic effects on the osmotic regulation and nutrient uptake processes of certain algae rather than as a response to community turnover or top-down control. Our study can help to put in place mitigation strategies for salinization and eutrophication, which often co-occur in freshwater ecosystems.
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