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Effects of seawater mixing on the mobility of trace elements in acid phosphogypsum leachates Texte intégral
2018
Papaslioti, Evgenia-Maria | Pérez López, Rafael | Parviainen, Annika | Sarmiento, Aguasanta M. | Nieto, José M. | Marchesi, Claudio | Delgado-Huertas, Antonio | Garrido, Carlos J.
Effects of seawater mixing on the mobility of trace elements in acid phosphogypsum leachates Texte intégral
2018
Papaslioti, Evgenia-Maria | Pérez López, Rafael | Parviainen, Annika | Sarmiento, Aguasanta M. | Nieto, José M. | Marchesi, Claudio | Delgado-Huertas, Antonio | Garrido, Carlos J.
This research reports the effects of pH increase on contaminant mobility in phosphogypsum leachates by seawater mixing, as occurs with dumpings on marine environments. Acid leachates from a phosphogypsum stack located in the Estuary of Huelva (Spain) were mixed with seawater to achieve gradually pH7. Concentrations of Al, Fe, Cr, Pb and U in mixed solutions significantly decreased with increasing pH by sorption and/or precipitation processes. Nevertheless, this study provides insight into the high contribution of the phosphogypsum stack to the release of other toxic elements (Co, Ni, Cu, Zn, As, Cd and Sb) to the coastal areas, as 80–100% of their initial concentrations behaved conservatively in mixing solutions with no participation in sorption processes. Stable isotopes ruled out connexion between different phosphogypsum-related wastewaters and unveiled possible weathering inputs of estuarine waters to the stack. The urgency of adopting effective restoration measures in the study area is also stressed.
Afficher plus [+] Moins [-]Effects of seawater mixing on the mobility of trace elements in acid phosphogypsum leachates Texte intégral
2018
Papaslioti, Evgenia-Maria | Pérez-López, Rafael | Parviainen, Annika Jenni Johana | Sarmiento, Aguasanta M. | Nieto, José Miguel | Marchesi, Claudio | Delgado-Huertas, Antonio | Garrido, Carlos Jesús
This work was supported by the Regional Government of Andalusia through the research project FOREVER (P12-RNM-2260) and the Spanish Ministry of Economic and Competitiveness through the research project CAPOTE (CGL2017-86050-R). The authors are very grateful to the funding support for the Committee of Experts on “The environmental diagnosis and the proposal of measures of restoration of the phosphogypsum stacks of Huelva”, appointed by the City Hall of Huelva. Dr. A Parviainen acknowledges the ‘Juan de la Cierva – Formación’ (FJCI-2014-19582) Fellowship and Dr. C. Marchesi the “Ramón y Cajal” (RYC-2012-11314) Fellowship financed by the Spanish Ministry of Economy and Competitiveness. | This research reports the effects of pH increase on contaminant mobility in phosphogypsum leachates by seawater mixing, as occurs with dumpings on marine environments. Acid leachates from a phosphogypsum stack located in the Estuary of Huelva (Spain) were mixed with seawater to achieve gradually pH 7. Concentrations of Al, Fe, Cr, Pb and U in mixed solutions significantly decreased with increasing pH by sorption and/or precipitation processes. Nevertheless, this study provides insight into the high contribution of the phosphogypsum stack to the release of other toxic elements (Co, Ni, Cu, Zn, As, Cd and Sb) to the coastal areas, as 80–100% of their initial concentrations behaved conservatively in mixing solutions with no participation in sorption processes. Stable isotopes ruled out connexion between different phosphogypsum-related wastewaters and unveiled possible weathering inputs of estuarine waters to the stack. The urgency of adopting effective restoration measures in the study area is also stressed. | Regional Government of Andalusia FOREVER (P12-RNM-2260) | Spanish Ministry of Economy and Competitiveness CAPOTE (CGL2017-86050-R), (FJCI-2014-19582), (RYC-2012-11314) | Committee of Experts, City Hall of Huelva
Afficher plus [+] Moins [-]Spatial distribution and ecological risk assessment of heavy metals in coastal surface sediments in the Hebei Province offshore area, Bohai Sea, China Texte intégral
2018
Ding, Xigui | Ye, Siyuan | Yuan, Hongming | Krauss, Ken W.
Seven hundred and nine surface sediment samples, along with deeper sediment samples, were collected from Hebei Province along the coastal section of the Bohai Sea, China, and analyzed for grain size, concentrations of organic carbon (Corg) and heavy metals (Cu, Pb, Zn, Cr, Cd, As, and Hg). Results indicated that the average concentrations in the sediments were 16.1 mg/kg (Cu), 19.4 mg/kg (Pb), 50 mg/kg (Zn), 48.8 mg/kg (Cr), 0.1 mg/kg (Cd), 8.4 mg/kg (As), and 20.3 μg/kg (Hg). These concentrations generally met the China Marine Sediment Quality criteria. However, both pollution assessments indicated moderate to strong Cd and Hg contamination in the study area. The potential ecological risk index suggested that the combined ecological risk of the seven studied metals may be low, but that 24.5% of the sites, where sediments were finer and higher in Corg concentration, had high ecological risk in Hg and Cd pollution.
Afficher plus [+] Moins [-]Troubles in the paradise: Litter and its scenic impact on the North Santa Catarina island beaches, Brazil Texte intégral
2018
Corraini, Natália Ramos | de Souza de Lima, André | Bonetti, Jarbas | Rangel-Buitrago, Nelson
Eight touristic beaches along the north coast of Santa Catarina Island, Brazil were assessed to determine litter influence on scenic quality. The application of the Coastal Scenic Evaluation System (CSES) categorized these beaches into four of the five available classes. Six of the investigated beaches belong to Class III (n = 3) and V (n = 3), while two beaches correspond to Class II and Class IV. Class I beaches were not found. A total amount of 4291 litter items weighing 29 kg were collected with average abundances of 0.29 items m2. Beach user's habits as well bad management practices along the adjoining river basins play an essential role on litter source, and are directly responsible for the decline of scenic quality of Santa Catarina Island Beaches. In fact, litter has a direct relation with the low scenic scores determined in the surveyed beaches.
Afficher plus [+] Moins [-]Perspectives on using marine species as bioindicators of plastic pollution Texte intégral
2018
Bonanno, Giuseppe | Orlando Bonaca, Martina
The ever-increasing level of marine pollution due to plastic debris is a globally recognized threat that needs effective actions of control and mitigation. Using marine organisms as bioindicators of plastic pollution can provide crucial information that would better integrate the spatial and temporal presence of plastic debris in the sea. Given their long and frequent migrations, numerous marine species that ingest plastics can provide information on the presence of plastic debris but only on large spatial and temporal scales, thus making it difficult to identify quantitative correlations of ingested plastics within well-defined spatio-temporal patterns. Given the complex dynamics of plastics in the sea, the biomonitoring of marine plastic debris should rely on the combination of several bioindicator species with different characteristics that complement each other. Other critical aspects include the standardization of sampling protocols, analytical detection methods and metrics to evaluate the effects of ingested plastics in marine species.
Afficher plus [+] Moins [-]Carapace asymmetry: A possible biomarker for metal accumulation in adult olive Ridleys marine turtles? Texte intégral
2018
Cortés-Gómez, Adriana A. | Romero, Diego | Girondot, Marc
The Olive Ridley marine turtle (Lepidochelys olivacea) is characterized by individual morphological variability in the number and shape of scutes. The influence of pollutants on developmental instability and one of its consequences, the asymmetry of individuals, has been demonstrated in several species, especially invertebrates and some birds. However, the use of this asymmetry as a biomarker of contamination in adult individuals has never been explored. We developed an index to quantify developmental instability (DIx) based on the number and relative size of costal carapace scutes. The link between DIx and inorganic elements concentrations was explored in various tissues of stranded turtles from the Southern Mexican Pacific. The relationships between adult contamination and DIx could directly or indirectly reflect (i) the disruption of metal elimination in the adult stage dependent on embryonic perturbation and thus determining DIx, (ii) the difference in metal absorption dependent on DIx status, or (iii) DIx linked to other unknown factors.
Afficher plus [+] Moins [-]Technologies for the marking of fishing gear to identify gear components entangled on marine animals and to reduce abandoned, lost or otherwise discarded fishing gear Texte intégral
2018
He, Pingguo | Suuronen, Petri
Technologies for the marking of fishing gear to identify gear components entangled on marine animals and to reduce abandoned, lost or otherwise discarded fishing gear Texte intégral
2018
He, Pingguo | Suuronen, Petri
Fishing gears are marked to establish and inform origin, ownership and position. More recently, fishing gears are marked to aid in capacity control, reduce marine litter due to abandoned, lost or otherwise discarded fishing gear (ALDFG) and assist in its recovery, and to combat illegal, unreported and unregulated (IUU) fishing. Traditionally, physical marking, inscription, writing, color, shape, and tags have been used for ownership and capacity purposes. Buoys, lights, flags, and radar reflectors are used for marking of position. More recently, electronic devices have been installed on marker buoys to enable easier relocation of the gear by owner vessels. This paper reviews gear marking technologies with focus on coded wire tags, radio frequency identification tags, Automatic Identification Systems, advanced electronic buoys for pelagic longlines and fish aggregating devices, and re-location technology if the gear becomes lost.
Afficher plus [+] Moins [-]Technologies for the marking of fishing gear to identify gear components entangled on marine animals and to reduce abandoned, lost or otherwise discarded fishing gear Texte intégral
2018
He, Pingguo | Suuronen, Petri | University of Massachusetts Dartmouth | Food and Agriculture Organisation of the United Nations | Luke / Luonnonvarat / Akvaattisten populaatioiden dynamiikka (4100110910) | 4100110910
Comparative risk assessment of spill response options for a deepwater oil well blowout: Part III. Stakeholder engagement Texte intégral
2018
Walker, Ann Hayward | Scholz, Debra | McPeek, Melinda | French-McCay, Deborah | Rowe, Jill | Bock, Michael | Robinson, Hilary | Wenning, Richard
This paper describes oil spill stakeholder engagement in a recent comparative risk assessment (CRA) project that examined the tradeoffs associated with a hypothetical offshore well blowout in the Gulf of Mexico, with a specific focus on subsea dispersant injection (SSDI) at the wellhead. SSDI is a new technology deployed during the Deepwater Horizon (DWH) oil spill response. Oil spill stakeholders include decision makers, who will consider whether to integrate SSDI into future tradeoff decisions. This CRA considered the tradeoffs associated with three sets of response strategies: (1) no intervention; (2) mechanical recovery, in-situ burning, and surface dispersants; and, (3) SSDI in addition to responses in (2). For context, the paper begins with a historical review of U.S. policy and engagement with oil spill stakeholders regarding dispersants. Stakeholder activities throughout the project involved decision-maker representatives and their advisors to inform the approach and consider CRA utility in future oil spill preparedness.
Afficher plus [+] Moins [-]Effects of CO2 enrichment on metal bioavailability and bioaccumulation using Mytilus galloprovincialis Texte intégral
2018
Passarelli, M.C. | Ray, S. | César, A. | DelValls, T.A. | Riba, I.
The main aim of this study was to evaluate the bioavailability of metals related to CO₂ enrichment on the mussels Mytilus galloprovincialis by metal's bioaccumulation analysis. Two sediment samples were selected and subjected to different pH levels. Concentrations of metals were measured in the overlying seawater and in the whole body of mussels exposed on the 7th, 14th and 21st days. Results showed that the CO₂ enrichment in aquatic ecosystems cause significant (p < 0.05) changes on the concentrations of Cu, Zn, Ni, Mn and As between the control pH and pH 7.0 after 7 days of exposure; and in the concentration of Fe at pH 6.0 using the RSP sediment. The multivariate analysis results showed that the increase in the bioaccumulation of some metals in mussels was linked to the acidification. It was concluded that many factors may interfere in the results when the acidification and bioavailability of metals are inquired.
Afficher plus [+] Moins [-]Method for reduction of the NOX emissions in marine auxiliary diesel engine using the fuel mixtures containing biodiesel using HCCI combustion Texte intégral
2018
Puškár, Michal | Kopas, Melichar | Puškár, Dušan | Lumnitzer, Ján | Faltinová, Eva
The marine auxiliary diesel engines installed in the large transoceanic ships are used in order to generate the electricity but at the same time these engines are able to produce a significant amount of the harmful exhaust gas emissions. Therefore the International Maritime Organisation (IMO) concluded an agreement, which has to control generating of gaseous emissions in maritime transport. From this reason started to be used some of the alternative fuels in this branch. There was performed a study, which investigated emissions of the auxiliary marine diesel engine during application of the experimental fuels. The different testing fuels were created using the ratios 0%, 50%, 80% and 100% between the biodiesel and the ULSDF (Ultra Low Sulphur Diesel Fuel). The experimental measurements were performed at the different engine loading levels and various engine speeds in order to investigate an influence of the mixed fuels on the engine operational characteristics.
Afficher plus [+] Moins [-]Sources of plutonium isotopes and 137Cs in coastal seawaters of Liaodong Bay and Bohai Strait, China and its environmental implications Texte intégral
2018
Hao, Yongpei | Xu, Yihong | Pan, Shaoming | Song, Xiaowei | Zhang, Kexin | Guo, Haiting | Gu, Zhi
In order to investigate the sources of plutonium in seawaters of Liaodong Bay and Bohai Strait, China, surface seawater samples were collected and analyzed for 239+240Pu and 137Cs by radiochemical separation combined with ICP-MS and γ-spectrometry, respectively. A large variation of 239+240Pu activities was observed, ranging from 1.993 to 29.677 mBq/m3 in the Liaodong Bay and from 0.932 to 10.183 mBq/m3 in the Bohai Strait. 137Cs activities showed little variation between the investigated locations, which was attributed to the different behavior characteristics of 239+240Pu and 137Cs in seawaters. The 240Pu/239Pu atom ratios showed a significant variation between the Liaodong Bay (0.185) and Bohai Strait (0.225), indicating that Pu derived from the Pacific Proving Grounds might have been transported to the Bohai Strait but not yet to the Liaodong Bay, which could further provide valuable reference for evaluating the seawater exchange cycle between the Bohai Sea and Yellow Sea.
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