Fluvial transport patterns of dissolved trace metals to the Ria of Cedeira

5 páginas.-- Interdisciplinary Water Congress CINA 2014, Vigo, 2-6 June 2014Samples of water were withdrawn monthly close to the Das Mestas River mouth, out of the tidal influence, from October 2011 to September 2012 (covering a hydrological year). After filtration through 0.45 policarbonate membrane, nine trace metals were analyzed (Al, Co, Cu, Cr, Fe, Mo, Ni, Pb and V) in the dissolved phase. All procedures were made following trace-metal-clean techniques. Three groups of metals were distinguished: Al, Co, Ni, Cu and Pb correlated with the SPM and the DOC indicating they are related with soil leaching; Iron is related with Chl-a so its behavior depends on the biologic activity; lithological influence on Cr, Mo and V patterns was observed.This study was supported by CTM2011-28792-C02 project, Land-sea exchange of trace metals and its importance for marine phytoplankton in an upwelling coast (MITOFE), financed by Spanish MINECOPeer reviewe

Trace element patterns in heterogeneous land–sea sediments: a comprehensive study of the Ulla–Arousa system (SW Europe)

In the continuum of the land–sea interface, sediment reservoirs are often considered separately. Therefore, integrative research is necessary. This study focuses on sediments throughout the tributaries–river–estuary–ria pathway of the Ulla–Arousa system, aiming to quantify trace element contents, identify land sources, determine background levels, and assess sediment enrichment and contamination states. The elements Al, As, Cr, Cu, Fe, Ni, Pb, Sb, U, and Zn were determined in 78 sediment stations. Two approaches were considered. First, background functions and enrichment factors were estimated using Al or U as the reference element. Second, a statistical study was conducted using distribution analysis, which helped identify trace element sources and their influences throughout the basin. The results revealed two significant sources of trace elements. One source is the amphibolite massif of the Arinteiro Unit, influencing the Brandelos (Cu) and Lañas (Fe) tributaries. Another source is the Deza tributary (As, Sb). However, these alterations do not reach the estuary, where anthropogenic sources (Cr, Cu, Ni) dominate. In the inner Ria of Arousa, only a light Cr enrichment was observed. The integrated study of the Ulla–Arousa system provides valuable patterns to understand and address heterogeneous land–sea systems.Consejo Superior de Investigaciones Científicas | Ref. 20181970Xunta de Galicia | Ref. IN607A2021/04Xunta de Galicia | Ref. ED481D 2023/006Consejo Superior de Investigaciones Científicas | Ref. JAEICU-20-IIM-0

Macroelements and Trace Elements Content in Brine-Canned Mackerel (Scomber colias) Subjected to High-Pressure Processing and Frozen Storage

This study analysed the effect of prior high-pressure processing (HPP; 200–600 MPa, 2 min), freezing (−30 °C, 48 h), and frozen storage (−18 °C, 6 months) on the macroelement and trace element content in brine-canned mackerel (Scomber colias). Most elements (Na, Ca, Ba, Mn, Fe, Cu, Cd, Sn, As, S, and Se) showed an increased (p < 0.05) presence in mackerel muscle canned after freezing. A content increase (p < 0.05) was also observed for Na and Sn if prior frozen storage was also applied; on the contrary, Ca, Ba, Mn, Fe, Cd, S, and Se showed a content decrease (p < 0.05) as a result of such storage. Freezing, frozen storage, and canning led to lower values (p < 0.05) in canned fish for K, Mg, Pb, and P. Prior HPP led to relevant content decreases (p < 0.05) for K, Mg, Ca, Ba, Mn, Fe, Pb, and P contents in fish canned after the freezing step; HPP provoked additional decreases (p < 0.05) in Ca, Ba, and Mn levels in samples corresponding to 6-month frozen storage. On the contrary, prior HPP led to marked increases (p < 0.05) for Cd, S, and Se contents in all canned samples. Content changes are explained on the basis of modifications of other constituents and liquor losses from muscleThis study was supported by the Spanish “Consejo Superior de Investigaciones Científicas (CSIC)” (Research Project 2017-70E032)S

Uranium as reference element to estimate the background of “Anthropocene” sensitive trace elements in sediments of the land-ocean continuum (Ulla-Arousa, NW Iberian Atlantic Margin)

Determining the background is a crucial step in differentiating between natural and anthropogenic components in environmental samples. Geochemical normalization is a standard procedure for determining the background contents of trace elements in sediment samples, which involves the careful selection of a reference element. Aluminum (Al), iron (Fe), and other major, minor, and even trace constituents of sediments are commonly used as reference elements. A suitable reference element should behave conservatively, with contents that are not significantly affected by anthropogenic factors or post-depositional processes. In this study, the performance of uranium as a reference element in sediment samples taken from the Ulla River was tested. The Ulla River drains a mainly granitic basin in the Iberian Atlantic Margin, and samples were collected from headwaters to the coastal area. Iterative least squares simple regression was used to estimate the background contents (as background functions) of six trace elements of environmental concern, including arsenic (As), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn). Uranium demonstrated satisfactory performance with correlation coefficients ranging from approximately 0.7 for Cu to 0.9 for As. The background-estimated contents of the six target elements were in good agreement with several references at different geographical scales, with differences possibly attributed to peculiarities in the local lithology. Thus, uranium can be considered a suitable normalizing element. However, it was tested in a relatively homogenous granitic basin and, like any other reference element, should not be used automatically without empirical corroboration.Xunta de Galicia | Ref. ED481B-2019-066Xunta de Galicia | Ref. IN607A2021/04Universidade de Vigo/CISU

Interviews between employees and customers during a company restructuring process

This work is the result of the discursive research carried out at a company involved in a restructuring programme, aimed at implementing a series of changes following the awarding of a new contract for the management of the city’s water supply and sewerage system. This change in management from a public (the City Hall) to a semi-private enterprise resulted in a great deal of confusion among certain sectors of the population. As a result, employees found themselves having to deal with large numbers of complaints on a daily basis without having received any prior communicative training in order to help them resolve these situations. Our empirical data (audio taped data) consists of 16 interviews between company employees and citizens analysed from the methodology based on Interactional Sociolinguistics, Ethnography of Communication, and Critical Discourse Analysis. Our study focuses on conflicts caused by situations of interactional asymmetry between the discourse of employees and customers, the result of the social inequality that exists in terms of citizens’ access to institutional discourse. An analysis of all the interviews reveals that employees use two different strategies in order to mitigate conflicts. These strategies can be classed as personalising or depersonalising. Our analysis shows that the use of these strategies is not always appropriate, and that their success or failure depends on the type of customers and their discursive resources. The problem is also frequently made worse by the employees’ rather limited communicative repertory and their consequent inability to redress the asymmetrical imbalance associated with this type of discourse and provide an effective approach and response to the various types of customers visiting the company’s offices

Translingual Practices and Reconstruction of Identities in Maghrebi Students in Galicia

In this article, we explore the emergence of a new translingual repertoire among young adolescents of Moroccan and Algerian origin in Galicia and the role it plays in reconstructing the transnational identity of young people within the Maghrebi diaspora. The data include a multimodal corpus with spoken and written interactions, collected as part of a classroom action research project, in which each student reconstructed their family and school language repertoire, as well as a WhatsApp group chat set up with the same young people. The results of our analysis reveal how the intercrossing of parental and adolescent agency plays a crucial role in dealing with the new multilingual translingual repertoire. The findings also indicate how this repertoire is deeply rooted in Moroccan Arabic as the family language and the incorporation of local languages, namely Spanish and Galician, and relies heavily on translingual multimodal practices, associated with transnational trajectories and the local schooling process of these young people

Background of u and th in sediments of bedrock rivers

The Miño River is a good example of bedrock rivers, where sediment geochemistry is scarcely studied. Its urban reach when passing through the city of Ourense gathers some characteristics that provide interest to its sediments, like scarcity of fine sediments accumulation and the impact of several human activities. Sediments trapped by potholes and other rock cavities were considered. In order to evaluate society-nature interactions through sediment composition it is critical to determine the compositional background (in absence of human alterations), particularly when working with trace elements. This work presents an exploratory assay to determine background in sediments from bedrock rivers by using two uncommon elements, uranium (U) and thorium (Th). To determine their background different statistical techniques were applied in order to set the background composition value and calculate possible enrichments. Background was calculated by simple least squares lineal regression by using Al as independent variable (reference element) resulting in 8.7 mgU kg-1 and 5.6 mgTh kg-1. Enrichments were found in some particular samples and can be attributed to intrinsic microenvironment complexities inside rock cavities

Interviews between employees and customers during the process of restructuring a company

This article is the result of discursive research carried out at a company involved in a restructuring programme, aimed at implementing a series of changes following the awarding of a new contract to manage a city’s water supply and sewerage system. This change in management from a public (City Hall) to a semi-private enterprise resulted in a great deal of confusion among certain sectors of the population. As a result, employees found themselves having to deal with large numbers of complaints on a daily basis without having received any prior communicative training in order to help them resolve these situations. Our empirical (audio-taped) data consist of 16 interviews between company employees and citizens analysed using methodology based on Interactional Sociolinguistics, Ethnography of Communication, and Critical Discourse Analysis. Our study focuses on conflicts caused by situations of interactional asymmetry between the discourse of employees and customers, the result of the social inequality that exists in terms of citizens’ access to institutional discourse. Analysis of all the interviews reveals that employees use two different strategies in order to mitigate conflicts. These strategies can be classed as personalizing or depersonalizing. Our analysis shows that the use of these strategies is not always appropriate, and that their success or failure depends on the types of customers and their discursive resources. The problem is also frequently made worse by the employees’ rather limited communicative repertory and their consequent inability to redress the asymmetrical imbalance associated with this type of discourse and provide an effective approach and response to the various types of customers visiting the company’s offices

Procesos de agentividad y nuevos repertorios translingüísticos de los estudiantes de origen magrebí en Galicia

«Agency processes and the new translinguistic repertoire of students of Moroccan and Algerian origin in Galicia». This article analyzes how agency processes are crucial in the management of the new translinguistic repertoire of high school students of Moroccan and Algerian origin in Galicia. The data include a multimodal corpus with spoken and written interactions collected as part of a classroom research-action, whereby each student reconstructed their family and school language repertoire, as well as a WhatsApp group chat set up with the same young people. Our analysis indicates how this repertoire is deeply rooted in Moroccan Arabic as the family language and the incorporation of local languages, namely Spanish and Galician, and relies heavily on translingual multimodal practices, associated with transnational trajectories and the local schooling process of these young people.Este artículo analiza cómo los procesos de agentividad son cruciales en la gestión del nuevo repertorio translingüístico de los estudiantes de secundaria de origen marroquí y argelino en Galicia. Los datos que analizaremos se componen de un corpus multimodal que incluye: interacciones orales y escritas, un chat de WhatsApp y prácticas comunicativas diversas, recogidas en el marco de una investigación-acción en el aula basada en un enfoque sociolingüístico etnográfico Los resultados del análisis muestran que el repertorio translingüístico emergente presenta un fuerte arraigo del árabe marroquí como lengua familiar y la incorporación de las lenguas locales −el español y el gallego− y el uso de prácticas multimodales translingüísticas, conectadas con las trayectorias transnacionales y el proceso de escolarización local de estos jóvenes