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Impact of atmospheric deposition of anthropogenic and natural trace metals on Northwestern Mediterranean surface waters: A box model assessment Texte intégral
2011
Heimbuerger, Lars-eric | Migon, Christophe | Cossa, Daniel
Under stratified oligotrophic conditions (May November), the surface mixed layer of the Northwestern Mediterranean constitutes a homogeneous water volume of 10-30 m depth. In other respects, the mean residence time of Ligurian surface waters (0-200 m) is 102 days. It is therefore possible to quantify the extent to which atmospheric deposition of trace metals affects surface waters. On the basis of literature data on anthropogenic and natural trace metals, we demonstrate that the ratios between total seawater labile atmospheric deposition during 102 days (Delta c) and dissolved TM concentrations in Ligurian surface waters (c) illustrate the impact of atmospheric deposition on surface seawater (Delta c/c). High ratios indicate surface TM enrichments, while low ratios indicate surface TM depletion, due to the quasi-complete sorption and removal of TMs by plankton during spring bloom. The simple box model proposed here may be used for other marine regions where hydrodynamical and physico-chemical constraints are well defined. (C) 2011 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Atmospheric concentrations, occurrence and deposition of persistent organic pollutants (POPs) in a Mediterranean coastal site (Etang de Thau, France) Texte intégral
2011
Castro Jimenez, Javier | Mariani, G. | Vives, I. | Skejo, H. | Umlauf, G. | Zaldivar, J. M. | Dueri, Sibylle | Messiaen, Gregory | Laugier, Thierry
Atmospheric concentrations and deposition fluxes of PCDD/F and PCB have been evaluated over a 1-year period in a Mediterranean coastal lagoon (Etang de Thau, France). Indicative PBDE air concentrations in the hot season are also reported in this work. ∑2,3,7,8-PCDD/Fs and ∑18PCBs (gas + particulate) air concentrations ranged from 67 to 1700 fg m−3 and from 13 to 95 pg m−3, respectively whereas ∑8PBDEs (gas + particulate) summer time levels varied from 158 to 230 pg m−3. The PCDD/F and PCB atmospheric occurrence over Thau lagoon and subsequent inputs to the surface waters are determined by an assemble of factors, being the seasonality of atmospheric concentration, the air mass origin and meteorological conditions important drivers. Total (wet + dry) ∑2,3,7,8-PCDD/Fs and ∑18PCBs deposition fluxes to Thau Lagoon waters are 117 and 715 pg m−2 d−1, respectively.
Afficher plus [+] Moins [-]Assessment of organotin (butyltin species) contamination in marine biota from the Eastern Aegean Sea, Turkey Texte intégral
2011
Kucuksezgin, F. | Aydin-Onen, S. | Gonul, L.T. | Pazi, I. | Kocak, F.
The marine environment continues to be adversely affected by tributyltin (TBT) release from maritime traffic. Therefore the concentrations of TBT, dibutyltin (DBT) and monobutyltin (MBT) were measured in barnacles, mussels and fish along the Eastern Aegean coastline. The average concentrations of TBT ngSng⁻¹ were found to be 235 in fish, 116 in mussels and 635 in barnacles. The highest concentrations of TBT, DBT and MBT were observed in the barnacles which had been sampled in marinas and harbors. All mussels sampled showed values of TBT+DBT, which were below the “tolerable average residue level (TARL)” as currently accepted. This indicates a lack of risk to the consumer. However, 7 out of the 15 fish sampled displayed TBT+DBT levels above the TARL, which indicates that a fish consumer group may be at risk. Barnacles have high potential as biomonitors for the presence of organotin in the Aegean Sea.
Afficher plus [+] Moins [-]Removal fluxes of Mn and Fe from the nearshore waters along the west coast of Taiwan Texte intégral
2011
Wei, Ching-Ling | Jiann, Kuo-Tung | Wen, Liang-Saw | Tsai, Jing-Ru | Sheu, David D.
Dissolved and particulate Mn and Fe in the nearshore waters were determined at 27 stations along the west coast of Taiwan during 19–23 November 2004. The latitudinal distributions of Mn and Fe were very similar; however, the concentration in the dissolved phase was lower, whereas that in the particulate phase was higher in the northern regime. The higher percentage of Fe than Mn that was associated with particles resulted in a two-order of magnitude higher particle–water partition coefficient for Fe, Kd(Fe), than that for Mn, Kd(Mn). The removal fluxes of Mn and Fe could be estimated by multiplying the particulate ²³⁴Th removal flux with the Mn/²³⁴Th and Fe/²³⁴Th ratios in suspended particles, which ranged from 0.1 to 3.8mmolm⁻²d⁻¹ for Mn, and from 3.4 to 194.5mmolm⁻²d⁻¹ for Fe. Residence times ranged from 1 to 20days for Mn and Fe were estimated in the nearshore.
Afficher plus [+] Moins [-]In situ biomonitoring of caged, juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Lower Duwamish Waterway Texte intégral
2011
Kelley, Matthew A. | Gillespie, Annika | Zhou, Guo-Dong | Zhang, Shu | Meador, James P. | Duncan, Bruce | Donnelly, K. C. | McDonald, Thomas J.
Contaminated sediments may have wide-ranging impacts on human and ecological health. A series of in situ caged exposure studies using juvenile Chinook salmon was conducted in the Lower Duwamish Waterway (LDW). Chemical analysis of sediment, water, and fish tissue were completed. Additionally, in 2004, DNA adducts in hepatic and gill tissues were measured. Gills contained significantly higher DNA adducts at stations B2 and B4, prompting further analysis of gills in 2006 and 2007. Fluorescent aromatic compounds (FACs) in bile, and CYP1A1 in hepatic tissue were also measured during 2006 and 2007, respectively. FACs in field-caged fish were comparable or significantly higher than wild-caught fish LDW fish and significantly higher than lab fish after only 8–10days, demonstrating the equivalency of exposure to that of migrating salmon. Furthermore, selected biomarkers appear to be capable of detecting spikes in contamination between sampling years, emphasizing the need for multiple year data collection.
Afficher plus [+] Moins [-]Metal enrichment in beach sediments from Chennai Metropolis, SE coast of India Texte intégral
2011
Santhiya, G. | Lakshumanan, C. | Jonathan, M.P. | Roy, P.D. | Navarrete-Lopez, M. | Srinivasalu, S. | Uma-Maheswari, B. | Krishnakumar, P.
A survey on the Partially Extracted Trace Metals (PETMs) concentration (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd) in beach sediments is reported for the first time from 57 different locations in Chennai Metropolitan City of Southeast coast of India. The concentration of PETMs suggests that they are mainly concentrated with organic matter in the crowded part of the industrial regions in the beaches from the northern part rather than the tourist beaches in the southern part of the city. The comparison on enrichment of trace metals indicates higher values of Pb, Ni in the beaches than lowest effect level (LEL) and effects range low (ERL) than the tourist beaches.
Afficher plus [+] Moins [-]Temporal and spatial biomonitoring of heavy metals in eastern Aegean coastal waters using Amphibalanus amphitrite Texte intégral
2011
Aydin Onen, S. | Kucuksezgin, F. | Kocak, F.
This biomonitoring study presents the spatial and temporal distributions of heavy metals in the soft tissues of a major fouling species Amphibalanus amphitrite living on hard substrate at different sites along the eastern Aegean coast. A. amphitrite has been chosen as a strong candidate for monitoring heavy metals. Sediment and seawater samples were also collected to detect their metal contents in order to gain more information on the environmental conditions and possible bioaccumulation patterns. The physico-chemical characteristics of sampling stations have been measured in order to characterize the sampling area. The order of metal concentrations in barnacles, sediment and seawater decreased in the following order Cu>Fe>Zn>Mn>Cd>Cr>Pb>Hg, Fe>Mn>Zn>Cu>Pb>Cr>Hg>Cd and Fe>Zn>Mn>Cu>Pb>Cr>Cd>Hg, respectively. These results showed that barnacles accumulate Cu in a higher degree than both sediment and seawater. Moreover, metal concentrations in barnacle have the potential for use in any future regulatory framework monitoring and eventually controlling ambient metal pollution levels.
Afficher plus [+] Moins [-]The use of plastic debris as nesting material by a colonial seabird and associated entanglement mortality Texte intégral
2011
Votier, Stephen C. | Archibald, Kirsten | Morgan, Greg | Morgan, Lisa
Entanglement with plastic debris is a major cause of mortality in marine taxa, but the population-level consequences are unknown. Some seabirds collect marine debris for nesting material, which may lead to entanglement. Here we investigate the use of plastics as nesting material by northern gannets Morus bassanus and assess the associated levels of mortality. On average gannet nests contained 469.91g (range 0–1293g) of plastic, equating to an estimated colony total of 18.46 tonnes (range 4.47–42.34tonnes). The majority of nesting material was synthetic rope, which appears to be used preferentially. On average 62.85±26.84 (range minima 33–109) birds were entangled each year, totalling 525 individuals over eight years, the majority of which were nestlings. Although mortality rates are high, they are unlikely to have population-level effects. The use of synthetic fibres as nesting material is a common strategy among seabirds, but the impacts of entanglement warrants further investigation.
Afficher plus [+] Moins [-]Assessment of phosphogypsum impact on the salt-marshes of the Tinto river (SW Spain): Role of natural attenuation processes Texte intégral
2011
Pérez López, Rafael | Castillo, Julio | Sarmiento, Aguasanta M. | Nieto, José M.
About 120Mton of phosphogypsum from the fertiliser industry were stack-piled on the salt-marshes of the Tinto river (Spain). This paper investigates the capacity of salt-marshes to attenuate contamination due to downward leaching from phosphogypsum. Solids and pore-waters were characterized at different depths of the pile to reach the marsh-ground. In superficial zones, metals were highly mobile, and no reduced sulphur was found. However, pollutant concentration decreased in the pore-water in deeper oxygen-restricted zones. Metal removal occurred by precipitation of newly formed sulphides, being this process main responsible for the contamination attenuation. Pyrite-S was the main sulphide component (up to 2528mg/kg) and occurred as framboids, leading to high degrees of pyritization (up to 97%). The sulphidization reaction is Fe-limited; however, excess of acid-volatile sulphide over other metals cause precipitation of other sulphides, mainly of Cu and As. This decrease in metal mobility significantly minimises the impact of phosphogypsums on the salt-marshes.
Afficher plus [+] Moins [-]Increased plastic litter cover affects the foraging activity of the sandy intertidal gastropod Nassarius pullus Texte intégral
2011
Aloy, Alexander B. | Vallejo, Benjamin M., Jr | Juinio-Meñez, Marie Antonette
This study analyzed the foraging behavior of the gastropod Nassarius pullus on garbage-impacted sandy shores of Talim Bay, Batangas, Philippines. The effect of different levels of plastic garbage cover on foraging efficiency was investigated. Controlled in situ baiting experiments were conducted to quantify aspects of foraging behavior as affected by the levels of plastic litter cover in the foraging area. The results of the study indicated that the gastropod’s efficiency in locating and in moving towards a food item generally decreased as the level of plastic cover increased. Prolonged food searching time and increased self-burial in sand were highly correlated with increased plastic cover. The accuracy of orientation towards the actual position of the bait decreased significantly when the amount of plastic cover increased to 50%. These results are consistent with the significant decreases in the abundance of the gastropod observed during periods of deposition of large amounts of plastic and other debris on the shore.
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