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Metal composition and fluxes of sinking particles and post-depositional transformation in a ria coastal system (NW Iberian Peninsula)
11 páginas, 7 figuras, 7 tablas ; The intra annual variation of the quantity and composition of the sinking particles in a ria coastal system (Vigo Ria, Galicia, NW Iberian Peninsula) has been studied. Levels of particulate metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, U, V and Zn) were determined both in the labile (1 M HCl extraction) and in the total fraction. The levels and type of metals found in different seasons of the year depended upon oceanographic, physical, chemical and biological conditions but, in general, lithogenic type metals (Al, Fe, Ti, U and V) were higher during winter rainy campaigns when high quantities of SPM were recovered in the trap. However, the more biogenic metals (Cu, Pb and Zn) followed a scattered variation. Vertical fluxes values varied within the following intervals: 0.4–6.1 g m− 2 d− 1 for Al, 0.7–7.6 μg m− 2 d− 1 for Cd, 0.1–0.6 mg m− 2 d− 1 for Co, 0.8–6.4 mg m− 2 d− 1 for Cr, 1.2–10.9 mg m− 2 d− 1 for Cu, 0.3–2.7 g m− 2 d− 1 for Fe, 1.8–19.8 mg m− 2 d− 1 for Mn, 0.5–2.9 mg m− 2 d− 1 for Ni, 1.7–7.9 mg m− 2 d− 1 for Pb, 0.1–0.2 g m− 2 d− 1 for Ti, 0.1–0.6 mg m− 2 d− 1 for U, 0.6–7.2 mg m− 2 d− 1 for V and 0.8–39.8 mg m− 2 d− 1 for Zn. In special, the deposited labile fraction is subject to postdepositional diagenetic processes with subsequent benthic fluxes of dissolved Cr, Cu, Mn, Ni, Pb and Zn form of the metals to the water column. For Co and Cd, however, their enrichment in the sediments compared to the traps suggests their association with a more refractory fraction upon postdepositional remineralization. This work represents one of the first studies about labile trace metal concentrations and intra annual variation in the particulate matter recovered from a sediment trap in a ria system. ; J. Santos-Echeandía thanks the Basque Government (post-doctoral grant) for the financial support. This work was supported by CICYT under the METRIA (ref. REN2003-04106-C03) and INTERESANTE (CTM2007-62546-C03-01/MAR) projects and is a contribution to the LOICZ-Spain program. ; Peer reviewed
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Piracy Cultures| European Cinema in P2P Networks: A New Distribution Model
The new peer-to-peer (P2P) technologies have impacted the film industry, which advocates sanctions against the downloading and sharing of products found on the Internet. But the economic effect of file sharing on the film industry remains difficult to determine. In this article, we ask whether file sharing networks will affect the survival or potential growth of European cinema. The steady decline in traditional film distribution channels for European productions—cinema theatres and direct sales or renting—is leading to the emergence of new distribution channels. And yet the results of the movie industry's calls—including those voiced by its European players—for stronger legislation against these same distribution channels are making their way through Europe by means of enforcement tools like HADOPI and other graduated response programs. Our hypothesis is that this offensive runs the risk of condemning a potential open distribution network and commons business model at its birth. For this, we start by clarifying the emerging global P2P phenomenon; we then stipulate what we mean by European cinema, outline its peculiar traits, and contrast it with North American cinema. Finally, we compare the consumption of European film in theatres with the availability of seeds and leechers for European cinema in P2P networks.
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The relevance of defining trace metal baselines in coastal waters at a regional scale: The case of the Portuguese coast (SW Europe)
14 páginas, 4 tablas, 10 figuras ; The Water Framework Directives aims a reduction in concentration of hazardous substances in the marine environment. Consequently, there is a need to distinguish between anthropogenically influenced metal concentrations from natural background levels. To better achieve this goal in the Portuguese coast, dissolved and particulate trace metal (TM) concentrations along the Portuguese coast were determined in 46 sites distance 1–3 km from the shoreline. Dissolved values ranged within the following intervals: 0.01–0.89 nM for Cd, 0.01–3.37 nM for Co, 0.90–45.4 nM for Cu, 3.30–140 pM for Hg, 1.88–15.1 nM for Ni, 0.01–0.15 nM for Pb and 1.40–62.0 nM for Zn. Whereas Cd, Co, Cu, Ni and Zn were enhanced in the southern coast, while Pb values were higher in the central part of the western coast. Mercury concentrations showed punctual increases all along the coast. Values of trace metals in suspended particulate matter varied in a broad range: 36–2902 μmol g−1 for Al, 0.10–15.1 nmol g−1 for Cd, 1.50–165 nmol g−1 for Co, 50.0–990 nmol g−1 for Cu, 2.80–76.4 nmol g−1 for Hg, 22–1471 nmol g−1 for Ni, 10.0–347 nmol g−1 for Pb and 416–10,981 nmol g−1 for Zn. Higher values for Al, Ni and Co were found in the central part of the western coast. However, Cd, Cu, Pb and Zn increased their levels from the north coast towards the central and south areas. The variability of both dissolved and particulate metals appears to be mainly associated with oceanographic conditions and continental inputs at North and central areas of the coast, and in the south coast to geological features rather than to anthropogenic pressures. On the basis of these results, regional baseline concentrations are proposed for the three typologies in Portuguese coastal waters defined under the Water Framework Directive ; Dr. Santos-Echeandia would like to thank the Basque Government for financial support (post-doctoral contract). ; Peer reviewed
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"Anthropocene" imprint of shipbuilding industry , blossom, decay and reactivation
2 pages.-- International Estuarine Biogeochemistry Symposium, Vigo (Spain), 4-5th June 2019 ; The globalization of the industrialization is being pointed out as the synchronous and global event that potentially marks the starting point of a current-proposed stratigraphic epoch: the 'Anthropocene'. Its study makes necessary high-resolution (yearly) works on recent stratigraphic records such as estuarine sediments. Concerning industrialization, the Ria of Ferrol represents a paradigmatic example in the NW of the Iberian Peninsula. This area is under the impact of military shipyards since 1730. Their maximum activity happened after 1947, consequence of the industry restructuring and the implementation of civil shipbuilding (including oil super-tankers). The present study focused on a sediment core of 50 cm long that holds record since the beginning of the 20th century, according to Pb-210 dating. Trace metal contents were evaluated to identify the human imprint. Background levels established in nearby areas with similar mineralogical characteristics were considered. Three main periods can be distinguished based on the trace-element to Al ratios: (i) from the beginning of the 20th century until about 1970, when ratios increase usually about 1.5 to 2.4 times, (ii) between around 1970 to 1990, when these ratios decrease usually about 1.4 to 2.3 times, and (iii) from 1990 to 2010, when ratios maintained. The studied sediments reflect the human-environment relationship in the area during the 20th century: the metal to Al ratios, sediment accumulation rates, total metal fluxes and enrichment factors show a first period of increasing industrialization without environmental concern, followed by an industrial collapse and a subsequent reactivation while implementing environmental friendly processes and policies ; This study from the project "Coastal contributions of trace elements during different oceanographic periods" (CTM2011-28792-C02-02), funded by MINECO ; Peer reviewed
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Contributions of trace elements to the sea by small uncontaminated rivers: Effects of a water reservoir and a wastewater treatment plant
14 pages, 3 tables, 5 figures ; Trace element contributions from small rivers to estuaries is an issue barely addressed in the literature. In this work, freshwater flowing into the Ria of Cedeira (NW Iberian Peninsula) was studied during a hydrological year through the input from three rivers, one considered uncontaminated (the Das-Mestas River), a second affected by urban treated wastewater discharges (the Condomiñas River), and the third containing a water reservoir for urban supply (the Forcadas River). With the objective of assessing the possible influence of human pressure, the annual yields for selected trace elements (Al, Fe, As, Cd, Co, Cr, Cu, Mn, Mo, Ni and Pb) were estimated and compared by normalizing by basin surface. Both dissolved and particulate transported elements were considered. After the data treatment and analysis it can be highlighted that: (i) the Das Mestas River is suitable to be included between the short European pristine baseline of small rivers, at least regarding the transported trace elements; (ii) natural enrichments were identified associated to the lithology of the basin in the Das-Mestas River (i.e. As) and in the Condomiñas River (i.e. Co, Cr and Ni); this fact highlights the importance of considering the local background for a proper assessment; (iii) the impoundment in the Forcadas River is related with a general decrease, even depletion, of the particulate and dissolved transported trace elements, except Mn; (iv) the discharge of sewage to the Condomiñas River is increasing the inputs to the ria of some trace elements in the particulate phase (i.e. Al, Cu and Pb). Both observed human-induced changes can be regarded as typical disturbances of trace element contributions from small rivers to estuaries ; M.A. Álvarez-Vázquez expresses gratitude for the support of 'Plan I2C (2011–2015)' of the 'Xunta de Galicia' in collaboration with the International 'Campus do Mar (ED481A-2015/410)' by means of a preDoc contract. This study was supported by the research subproject "Coastal contributions of trace elements during different oceanographic periods" (acronym: MEFIO, ref. CTM 2011-28792-C02-02) financed by 'Ministerio de Economía y Competitividad' of Spanish government ; Peer reviewed
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Correction to: Hg and Se composition in demersal deep-sea fish from the North-East Atlantic
In: Environmental science and pollution research: ESPR, Band 27, Heft 27, S. 33658-33658
ISSN: 1614-7499
Hg and Se composition in demersal deep-sea fish from the North-East Atlantic
In: Environmental science and pollution research: ESPR, Band 27, Heft 27, S. 33649-33657
ISSN: 1614-7499
Assessment of contaminants and biomarkers of exposure in wild and farmed seabass
In: Ecotoxicology and environmental safety: EES ; official journal of the International Society of Ecotoxicology and Environmental safety, Band 73, Heft 4, S. 579-588
ISSN: 1090-2414
Deep-sea mining: using hyperbaric conditions to study the impact of sediment plumes in the subtidal clam Spisula solida
In: Environmental science and pollution research: ESPR, Band 30, Heft 48, S. 105675-105684
ISSN: 1614-7499
Towards the Use of Dgt Technique in a Regulatory Context for Monitoring Metals in Marine Water Bodies: Results of an International Intercomparison Exercise
In: STOTEN-D-22-10078
SSRN
A new approach to using Diffusive Gradient in Thin-films (DGT) labile concentration for Water Framework Directive chemical status assessment: adaptation of Environmental Quality Standard to DGT for cadmium, nickel and lead
In: Environmental sciences Europe: ESEU, Band 35, Heft 1
ISSN: 2190-4715
AbstractIntegrative passive samplers, such as DGT (Diffusive Gradients in Thin-films), are identified in European Technical Guidance Documents as promising tools to improve the quality of the assessment, in the context of the WFD (EU Water Framework Directive). However, DGT results cannot yet be used directly in a regulatory framework to assess the chemical status of water bodies, as DGT labile concentrations cannot be directly compared to the metal AA-EQSmarine water (Annual Average Environmental Quality Standard) established by the WFD, which are defined in the dissolved concentration. Therefore, prior to using DGT results in a regulatory context, for cadmium, nickel and lead, an adaptation of existing AA-EQSmarine water for DGTs should be pursued, ensuring at least the same level of protection. In this sense, in the framework of the MONITOOL project, a robust database of dissolved and labile metal concentrations in transitional and coastal waters, for adapting the existing AA-EQSmarine water for DGT technique, was obtained. Building on these results, this study proposes a methodology and provides values and equations for using DGT results for the chemical status assessment of marine waters, by adapting the EQSmarine water to adapted EQSDGT or predicting dissolved concentrations from DGT results. Based on available dataset, a first simulation of "chemical status" assessment per MONITOOL sampling site using DGT measured labile concentrations was carried out and the results were compared to an assessment based on dissolved concentration to check their compliance. These results demonstrate that the use of DGT passive samplers is appropriate for the metal concentrations level encountered in the marine environment. Further work is recommended to test the effectiveness of the methodology proposed in this study under WFD conditions on more sites and to establish common strategy guidelines for the use of DGT passive samplers in monitoring.
One step from the deep ocean: Linking research and governance for the Tagus river estuary and the Lisbon canyon system – A conference report
In: Marine policy, Band 144, S. 105224
ISSN: 0308-597X