351 research outputs found

    Facies model, cementation and sedimentary evolution of a 20th-century beach and beachrock: The Gorrondatxe wave and tidal coastal system (NE Spain)

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    Lithology, bedding, and sedimentary structures of the Gorrondatxe coastal and beach system show an upper shoreface around the low-water level and containing the coarsest grain sizes; a foreshore in the main intertidal zone, which is mainly composed of sands with minor gravels and a distinctive low-angle, seaward-dipping, planar-parallel lamination; and a backshore zone with a mixture of marine-derived sands (washover) and nonmarine sands and muds (aeolian, subaerial ponds) above the high-tide water level. The facies model shows a wave-dominated, mesotidal, composite beach with a fining-upwards and aggradational trend. Over the 20th century, a beachrock developed in this area as a result of heavy-industry waste dumping (steel industry) off the coast, which later became attached to the coast. There are a variety of cements and degrees of lithification in the beachrock, suggesting that the beachrock-related processes, although coetaneous, were not similar in all these zones and that different cements developed at the same time. Sand cementation can be used to recognize such facies in the stratigraphic record or in well cores, when other kinds of data are not available. The upper shoreface sandstones are hard andwell-cemented, with awhitish circumgranular aragonite cement and good intergranular porosity; the foreshore sands are medium-hard, with a brown, irregular, aragonite needle cement, which shows higher intergranular porosity; finally, the backshore sands are only lightly cemented,with a brown aragonite and rhombohedral calcite cement, with the highest intergranular porosity. SEM images show the presence of Coccus-type bacteria in all the different facies and zones; these are the best proof of metabolic activity, probably of ureolytic bacteria, in the origin of all these cements.Over the course of the 20th century,Gorrondatxe evolved from a formerly dissipative, ridge and runnel beach to an active, aggrading and prograding, reflective beach, and finally to an inactive beach prone to erosion. The change to a reflective profile and the cementation of the beachrock indicate that anthropic offshore inputs were rapidly recycled into the beachface. Another major change occurred when waste discharges ended, and the former sediments and beachrock started to be eroded to their current state.The present study has been funded by the Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), research group GIU18/16317/05; MINECO/MCI/ERDF-EU project PID2019-105670GB-I00/AEI/10.13039/501100011033 of the Spanish Government

    Implantación de metodologías de planificación estratégica en la universidad, identificación de indicadores y medición de activos intangibles

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    Después del largo camino recorrido esta última década en la implantación de los programas de calidad en el sistema universitario español, se mantiene cierta incertidumbre sobre el grado de influencia de dichos programas en la toma de decisiones. En ese contexto se ha diseñado un estudio prospectivo, mediante la aplicación de la técnica de investigación social Delphi, con objeto de evaluar el grado de implantación de la metodología del Cuadro de Mando Integral (Balanced Scorecard) en las universidades de la Comunidad de Madrid, así como averiguar la opinión del grupo de expertos sobre la posibilidad de condensación de los indicadores y sobre la medición de activos intangibles. En la comunicación propuesta se incluirá un análisis de las conclusiones obtenidas

    Euroagro'98: novedades en maquinaria hortofrutícola

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    La 12a edición de la Feria Internacional de la Producción, Transformación y Comercialización Agrícola celebrada del 22 al 25 de abril en Valencia reunió a numerosos profesionales del sector hortofrutícola; empresas de maquinaria agrícola y aperos, de maquinaria postcosecha, envases, embalajes, fitosanitarios, grandes productores, etc

    La flora alóctona de Aragón (España)

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    En este trabajo, presentamos una aproximación a la flora alóctona de Aragón a partir de la información disponible en la bibliografía, complementada con la de nuestras propias observaciones y experiencia. Los resultados revelan que existen, al menos, 313 especies de plantas vasculares exóticas naturalizadas o subespontáneas en la región, de las cuales el 24 % manifiestan carácter invasor. No obstante, dentro de ellas solamente 17 son transformadoras, y menos aún las que suponen un riesgo para la conservación del medio natural. Pese a ello, no debe subestimarse la importancia del fenómeno por lo que recomendamos la vigilancia de las áreas más sensibles, que son, una vez más, los ambientes riparios y las comarcas de clima más suave.This paper examines the alien flora of Aragón (Spain), a vast region of the northeastern Iberian Peninsula. The source of data was mainly literature references, complemented with authors’ experience. We can stablish, by the results obtained, a regional catalogue of 313 alien vascular plants species, of which 17 are transformers. A number of them are potentially dangerous for natural ecosystems. We recommend be cautious and keeping watch on sensitive areas, as riparian habitats and temperate zones

    Contribution to the knowledge of alien vascular flora of Castilla and León

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    Se analizan algunas especies de flora vascular alóctona de Castilla y León (España

    Detección de la estabilidad del color y mezclas de pimentón molido utilizando reflexión óptica y análisis de imagen.

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    En la actualidad hay una gran diferencia en la calidad de pimentón molido procesado en "La Vera" por el método tradicional (secado con humo), y el procesado en otras regiones con métodos más rápidos y baratos (secado forzoso con estufa). Esto hace necesario disponer de un sistema capaz de establecer, por un lado, la estabilidad de carotenoides (responsables de la coloración), y por otro lado detectar diferente» grados de mezcla de pimentones de distintas calidades. Para determinar la estabilidad de color, en este estudio se ha empleado un proceso de envejecimiento acelerado mediante luz UV; se fabricó una cámara que degrada rápidamente el color de las muestras según su estabilidad de color. Como procedimiento de medida de dicho envejecimiento se ha testado la reflexión óptica y el análisis de imagen El primer procedimiento es por medio de reflexión óptica coa un espectrofotómetro modelo Minolta C-508Í, el segundo procedimiento es por medio de análisis de imagen Se realizaron muestras en cuatro fechas distintas para comprobar la repetibilidad del procedimiento, y con 35 muestras por fecha, que pertenecen a siete grupos de diferentes grados de mezcla de pimentón de La Vera y otro de peor calidad (1:0, 6:1.3:1. 1:1. 1:3. 1 6,0:1). Para la reflexión óptica se utilizó el espectro visible, entre 400 y 700 nm de longitud de onda, con una resolución de 20 nm. Para el análisis de imagen se obtuvo el histograma de imágenes en blanco y negro de las muestras. Del espectro y del histograma de cada una de las muestras se obtuvieron variables con las que se realizaron análisis estadísticos que permiten predecir la calidad de las muestras con un ajuste (r1) de 0.989 en el caso de reflexión óptica y 0.941 para el análisis de imagen

    Development of model based sensors for the supervision of a solar dryer

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    Solar dryers are increasingly used in developing countries as an alternative to drying in open air, however the inherent variability of the drying conditions during day and along year drive the need for achieving low cost sensors that would enable to characterize the drying process and to react accordingly. This paper provides three different and complementary approaches for model based sensors that make use of the psychrometric properties of the air inside the drying chamber and the temperature oscillations of the wood along day. The simplest smart sensor, Smart-1, using only two Sensirion sensors, allows to estimate the accumulated water extracted from wood along a complete drying cycle with a correlation coefficient of 0.97. Smart-2 is a model based sensor that relays on the diffusion kinetics by means of assesing temperature and relative humidity of the air inside the kiln. Smart-2 model allows to determine the diffusivity, being the average value of D for the drying cycle studied equal to 5.14 × 10−10 m2 s−1 and equal to 5.12 × 10−10 m2 s−1 for two experiments respectively. The multidistributed supervision of the dryer shows up the lack of uniformity in drying conditions supported by the wood planks located in the inner or center of the drying chamber where constant drying rate kinetics predominate. Finally, Smart-3 indicates a decreasing efficiency along the drying process from 0.9 to 0.

    Identifying efficient Nitrate reduction strategies in the Upper Danube

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    Nitrogen losses in the form of Nitrate (N-NO3) from point and diffuse sources of pollution are recognized to be the leading cause of water body impairment throughout Europe. Implementation of conservation programs is perceived as being crucial for restoring and protecting the good ecological status of freshwater bodies. The success of conservation programs depends on the efficient identification of management solutions with respect to the envisaged environmental and economic objectives. This is a complex task, especially considering that costs and effectiveness of conservation strategies depend on their locations. We applied a multi-objective, spatially explicit analysis tool, the R-SWAT-DM framework, to search for efficient, spatially-targeted solution of Nitrate abatement in the Upper Danube Basin. The Soil Water Assessment Tool (SWAT) model served as the nonpoint source pollution estimator for current conditions as well as for scenarios with modified agricultural practices and waste water treatment upgrading. A spatially explicit optimization analysis that considered point and diffuse sources of Nitrate was performed to search for strategies that could achieve largest pollution abatement at minimum cost. The set of optimal spatial conservation strategies identified in the Basin indicated that it could be possible to reduce Nitrate loads by more than 50% while simultaneously provide a higher income
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