Efecto del vertido de aguas residuales en el poblamiento de poliquetos en San Pedro del Pinatar

Los vertidos de aguas residuales son una de las principales fuentes de contaminación del medio marino. El objetivo principal de este estudio es determinar el grado de afección del vertido sobre el poblamiento de poliquetos asociado a fondos blandos. Las estaciones fueron distribuidas en dos transectos, uno de los cuales incluye la zona de influencia del vertido, y otro control a 4 km al sur. Se detectó una segregación del poblamiento de poliquetos en dos grandes grupos. Uno, caracterizado por una mayor proporción de fangos y materia orgánica; dominado por las familias Paraonidae, Lumbrineridae y Cirratulidae. El otro grupo, dominado por la familia Syllidae, se caracteriza por una gran heterogeneidad de los sedimentos Se observa una alta correlación entre los factores ambientales y la estructura del poblamiento de poliquetos.

Aspectos de la poliédrica influencia de los clásicos: nuevas imágenes clave de la influencia de san Vicente Ferrer en Italia

Este artículo analiza la función de la figura de san Vicente Ferrer en la política de afianzamiento y expansión de la Corona de Aragón en la Italia de mediados del siglo XV y hasta el siglo XVIII. San Vicente Ferrer, clásico innegable de la cultura de la Corona de Aragón, ejerció una extraordinaria influencia en el pensamiento, la predicación y la ortodoxia católicas, así como también, en el tablero de ajedrez de la alta política de fines del siglo XIV y principios del XV. Su influencia fue prácticamente ubicua y omnímoda: predicaba a las masas de casi toda Europa occidental, enfervorizadas por sus dotes oratorias y su dominio de las artes de la predicación, al mismo tiempo que ejercía de consejero de máxima confianza de papas, reyes y gobernantes, escribía densos tratados de teología y filosofía moral, y obraba milagros (más de 900 registrados en su Causa de Canonización). Caló muy hondo, también después de su muerte y durante siglos, en toda Italia, que era el gran escenario de la política y de la cultura humanística y del Renacimiento. Ello se aprovechó por parte de la Corona de Aragón para su expansión en Italia, desde la conquista de Nápoles por Alfonso el Magnánimo. Todo ello se analiza en este estudio a partir de obras de arte (capillas, cuadros, retablos, frescos y mosaicos), nunca tenidas en cuenta en este sentido, pero que, como queda demostrado, son muestra y prueba de esa influencia tanto religiosa como también política de la “figura” de este santo valenciano. Se trata en definitiva del análisis de la poliédrica función de los clásicos.

Relationship between static and dynamic elastic modulus of calcarenite heated at different temperatures: the San Julián's stone

The San Julián’s stone is the main material used to build the most important historical buildings in Alicante city (Spain). This paper describes the analysis developed to obtain the relationship between the static and the dynamic modulus of this sedimentary rock heated at different temperatures. The rock specimens have been subjected to heating processes at different temperatures to produce different levels of weathering on 24 specimens. The static and dynamic modulus has been measured for every specimen by means of the ISRM standard and ultrasonic tests, respectively. Finally, two analytic formulas are proposed for the relationship between the static and the dynamic modulus for this stone. The results have been compared with some relationships proposed by different researchers for other types of rock. The expressions presented in this paper can be useful for the analysis, using non-destructive techniques, of the integrity level of historical constructions built with San Julián’s stone affected by fires.

Benthic community recovery from brine impact after the implementation of mitigation measures

In many regions, seawater desalination is a growing industry that has its impact on benthic communities. This study analyses the effect on benthic communities of a mitigation measure applied to a brine discharge, using polychaete assemblages as indicator. An eight-year study was conducted at San Pedro del Pinatar (SE Spain) establishing a grid of 12 sites at a depth range of 29–38 m during autumn. Brine discharge started in 2006 and produced a significant decrease in abundance, richness and diversity of polychaete families at the location closest to the discharge, where salinity reached 49. In 2010, a diffuser was deployed at the end of the pipeline in order to increase the mixing, to reduce the impact on benthic communities. After implementation of this mitigation measure, the salinity measured close to discharge was less than 38.5 and a significant recovery in polychaete richness and diversity was detected, to levels similar to those before the discharge. A less evident recovery in abundance was also observed, probably due to different recovery rates of polychaete families. Some families like Paraonidae and Magelonidae were more tolerant to this impact. Others like Syllidae and Capitellidae recovered quickly, although still affected by the discharge, while some families such as Sabellidae and Cirratulidae appeared to recover more slowly.

Bioindicators as metrics for environmental monitoring of desalination plant discharges

Development of desalination projects requires simple methodologies and tools for cost-effective and environmentally-sensitive management. Sentinel taxa and biotic indices are easily interpreted in the perspective of environment management. Echinoderms are potential sentinel taxon to gauge the impact produced by brine discharge and the BOPA index is considered an effective tool for monitoring different types of impact. Salinity increase due to desalination brine discharge was evaluated in terms of these two indicators. They reflected the environmental impact and recovery after implementation of a mitigation measure. Echinoderms disappeared at the station closest to the discharge during the years with highest salinity and then recovered their abundance after installation of a diffuser reduced the salinity increase. In the same period, BOPA responded due to the decrease in sensitive amphipods and the increase in tolerant polychaete families when salinities rose. Although salinity changes explained most of the observed variability in both indicators, other abiotic parameters were also significant in explaining this variability.