Characterization and evolution of the sediments of a Mediterranean coastal lagoon located next to a former mining area

Coastal lagoons are ecosystems that are relatively enclosed water bodies under the influence of both the terrestrial and themarine environment, being vulnerable to human impacts. Human activities, such asmining extraction, are significant anthropogenic coastal stressors that can negatively affect ecosystems and communities. In light of the above, the objective of this research is to examine the influence ofmetal mining activities on the composition of sediments of a Mediterranean coastal lagoon, named Mar Menor. This paper presents a comprehensive characterization for grain size, mineralogy, geochemistry and organic matter of sediments of this coastal lagoon, investigating their variation along space and time. Sedimentation dynamics are ruling clearly the grain size predominant in each area of the MarMenor coastal lagoon, determining the existence of entrainment, transport and sedimentation areas. Forminerals, elements and organic matter, sedimentation dynamics are also determining their distribution.The authors would like to thank Fundación Séneca for funding the project 12038/PI/09. In addition, they want to acknowledge the cooperation of J.M. Peñas, R. Baños, J. Saura, M. Saura and B. Villaescusa who helped us to improve this research and to Mr. and Mrs. Purves for their English grammar supervision

The Influence of Mining Waste from the Sierra Minera (Cartagena-La Unión) on the Evolution of Sediments in the Mar Menor Coastal Lagoon

[SPA] El distrito minero de Cartagena-La Unión se encuentra situado junto al Mar Menor (SE, España), una de las mayores lagunas costeras mediterráneas. Aunque la actividad minera se detuvo hace varias décadas, los residuos mineros siguen entrando en la laguna, especialmente durante episodios de lluvias torrenciales, a través de ríos estacionales, localmente llamados “ramblas”. Esta entrada de residuos mineros puede llegar a afectar negativamente a los ecosistemas y sus comunidades. El objetivo del presente estudio fue examinar la influencia de la actividad minera metálica en la composición de los sedimentos del Mar Menor, realizando un estudio evolutivo de dichos sedimentos mediante una caracterización integral de la granulometría, mineralogía, geoquímica y la materia orgánica de los fondos de esta laguna costera, a lo largo del espacio y del tiempo. Como resultado se obtuvo que la dinámica de sedimentación ha influenciado claramente el tamaño de partícula predominante en cada área de la laguna costera, determinando la existencia de zonas de arrastre, transporte y sedimentación. La distribución de minerales, elementos y materia orgánica, también está determinada por esta dinámica de sedimentación.[ENG] The Cartagena-La Unión mining district is located close to the Mar Menor (SE Spain), one of the largest coastal lagoons in the Mediterranean Sea. Although no mining has been done for several decades mining waste continues to find its way into the lagoon, especially during periods of torrential rain, carried by flash floods that run along seasonal rivers or wadis. This input of mining waste can have a negative impact on the lagoon’s ecosystems and communities, and the purpose of this study was to evaluate the influence of metal ore mining on the composition of the sediments in the Mar Menor. The evolution of these sediments was studied by carrying out a comprehensive spatiotemporal characterization of the particle size distribution, mineralogy, geochemistry and organic matter of the seabed of this coastal lagoon. Results reveal that sedimentation dynamics has had a marked influence on predominant particle size in each area, determining the existence of clearly differentiated carryover, transport and sedimentation zones. The distribution of minerals, elements and organic material is also determined by the sedimentation dynamics in question

Diode switchable chiral metamaterial structure for polarization manipulation

This communication presents a novel diode switchable chiral metamaterial structure that manipulates the polarization in different ways depending on the active bias lines. Three different bias states that provide three totally different behaviors have been considered: polarization rotator, circular polarization converter and linear to circular converter.This work has been partially supported by the Spanish Government MINECO through the ERDF co-funded Research Projects TEC2014-55463-C3-1-P, TEC2014-55463-C3-2-P and TEC2014-55463-C3-3-P

Novel fishnet-like chiral metamaterial structure with negative refractive index and low losses

In this work a composed chiral metamaterial structure constituted by the combination of a composite chiral metamaterial and a modified fishnet structure is presented and numerically analyzed. This new fishnet-like chiral metamaterial features two wide frequency bands wherein the refractive indices are negative and exhibits lower losses than its constituents do.This work has been partially supported by the Spanish Government MINECO through the ERDF co-funded Research Projects TEC2014-55463-C3-1-P and TEC2014-55463-C3-3-P

Chiral metamaterial structure with high optical activity based on conjugated omega particles

In this communication the authors present a novel chiral metamaterial structure formed by planar omega particles These omega particles, arranged in conjugated pairs, present high optical activity. Thanks to the high values of chirality, the structure provides negative refractive index with high figure of merit.This work has been supported by the Spanish Government MINECO through the Research Projects TEC2014-55463-C3-1-P, TEC2014-55463-C3-3-P and by the European Commission (ERDF)

Design of electromagnetic band gap media based on crank-like chiral structures

A new EBG (Electromagnetic Band Gap) structure with chiral crank elements is presented and its effects on the electric field propagation along a microstrip line are analysed and compared with the effects produced by mushroom-type inclusions. Chiral crank inclusions are distributed along both sides of the strip and the corresponding results are compared with those obtained by other elements commonly used to create EBG media, mushroom-type structures. A single row of high chirality structures on both sides of a transmission line produces a band gap with a wider bandwidth than that obtained by the inclusion of other elements commonly used to create EBG media, such as mushroom-type structures. Unlike what happen with mushroomtype inclusions, more rows of chiral elements do not change significantly the central frequency and bandwidth of the band gap. The proposed structure works in X-Band (8.2-12.4 GHz) and it is easily adaptable to other frequencies by changing the size of the crank inclusions. Several samples have been made in FR-4 printed circuit board and a good agreement has been found between numerical analysis and experimental measurements.This work has been supported by the Ministerio de Economía y Competitividad of Spain (ERDF co-funded Research Projects PGC2018-098350-B-C21 and PGC2018-098350-B-C22

Contaminación por erosión eólica e hídrica de las áreas limítrofes a la antigua zona minera de La Unión (Cartagena)

The mining area of Cartagena – La Unión has been object of an intense exploitation for more than 2,500 years. In recent time in the second half of the XIX century and the fi rst of the XIX century mining activity was realized by underground galleries, but during second half of the XX century the exploitation was carried out to opencast, with an important earthwork, summarized in more than 360 million tons, of which 315 correspond to remainders. At the present time, the mining activity is inactive, but enormous amounts of mineral wastes exist (pyrite, galena and blende), that by their unstable characteristics and size of particles are easily mobilized, as much by the action of the wind like by the run-off waters. The heavy mineral contents of these remainders, specially of zinc and lead, are turned into possible polluting agents of the atmosphere and grounds of the adjacent areas. It is tried to evaluate the amount of mobilized material by the wind and the water, through collectors adapted for both erosive agents (aeolian and water erosion) and to determine the amount of heavy metals that are transported by the wind or run-off waters.El área minera de Cartagena – La Unión ha sido objeto de una intensa explotación desde hace más de 2.500 años. En época reciente, en la segunda mitad de siglo XIX y primera del siglo XX la actividad minera se realizó mediante galerías subterráneas, pero durante la segunda mitad del siglo XX la explotación se llevó a cabo a cielo abierto, con un importante movimiento de tierras, cifrado en mas de 360 millones de toneladas, de las que 315 corresponden a residuos. En la actualidad, la actividad minera está inactiva, pero existen enormes cantidades de desechos de mineral (pirita, galena y blenda), que por sus características inestables y tamaño de partículas son fácilmente movilizables, tanto por la acción del viento como por las aguas de escorrentía. Los contenidos en metales pesados de estos residuos, especialmente de cinc y plomo, los convierten en posibles contaminantes de la atmósfera y los suelos de las áreas colindantes. Con el presente trabajo se ha pretendido evaluar la cantidad de material movilizado por el viento y el agua, mediante colectores adecuados para ambos agentes erosivos (erosión eólica e hídrica) y determinar la cantidad de metales pesados que son transportados por el viento o arrastrados por las aguas de escorrentía

Social media hook sports events: a systematic review of engagement

Social media are nowadays used in all sectors, and likewise frequently within the sports industry. However, there is a lack of studies that offer a holistic understanding of the phenomenon of social media engagement (SME) in this area. Thus, the main object of the present study was the elaboration of a systematic review of the existing literature of the past ten years about SME within the field of sports events. The study was carried out following the PRISMA guidelines. By searching the databases Web of Science, Scopus, ProQuest, and Academic Search Ultimate, we identified 208 studies. After screening and reviewing for eligibility, we finally included 28 articles in the present study. The methodologies, types of analysis applied, main objectives, and the results on SME of the articles included in the synthesis were systematically reviewed. The findings showed that only four articles had as a principal theme the SME. Social media offer a useful tool for engagement, but SME adopts must still gain greater recognition. The need to co-create with users and engage them on social media, due to the great utility of social media in this sector is highlighted based on the results. It was found that SME around sports events remains an emerging and still developing research field which presents a wide range of future research lines

Waste management and contaminated soil from metal mining: technical aspects, environmental and regulatory framework

[SPA] El suelo es un recurso afectado por fuentes de contaminación que lo pueden convertir en un recurso contaminado. El contenido en metales pesados del suelo es uno de los criterios empleados para la estimación de la calidad ambiental del suelo, siendo necesario, el establecimiento de niveles de fondo en los metales y sus correspondientes niveles genéricos de referencia. El suelo tiene unos valores naturales de presencia de determinados elementos traza, metales, que son los valores de fondo, que generan un riesgo admisible. Pero cuando ese riesgo se convierte en inadmisible, se han de establecer otros valores. Estos valores serían los niveles genéricos de referencia del suelo, y son los valores que nos indicarán si estamos ante un suelo potencialmente contaminado, o contaminado. Los “elementos traza” aparecen mayoritariamente en los residuos mineros relativos a las industrias extractivas. Estos materiales ya sean residuos, recursos o subproductos reciben, por lo general, el tratamiento de residuos inertes, cuando en realidad deberían ser tratados como residuos peligrosos. El presente estudio critica las disposiciones normativas que regulan los residuos y suelos propios de los distritos de minería metálica, con la finalidad de proponer mejoras normativas que permitan la adecuación de la legislación aplicable a los nuevos conocimientos científico-técnicos. [ENG] Soil is a resource affected by sources of pollution that can become contaminated resource. The heavy metal content of the soil is one of the criteria for estimating the environmental quality of the soil, being necessary to establish background levels in metals and their corresponding levels generics de reference. The floor has natural presence values of certain trace elements, metals, which are the background values, which generate an acceptable risk. But when that risk becomes unacceptable, they have to set other values. These values would be the generic reference levels of soil, and are the values that will tell us if this is a potentially contaminated or contaminated soil. The "trace elements" appear mostly in mining waste relating to extractive industries. These materials either waste resources or byproducts are, in general, the treatment of inert waste, when they should be treated as hazardous waste. This study criticizes the regulatory provisions governing waste and soils own metal mining districts, in order to propose improvements regulations that facilitate adjustment of the legislation applicable to new scientific and technical knowledge.Agradecer al equipo del TAIDA el poder formar parte de este grupo de doctorado