La eficacia erosiva de la acción nival y su relación con la herencia geomorfológica: macizo de Peñalara, Sistema Central

[Resumen] [Abstract] An automatic station for monitoring bedload transport has been installed in a gravel-bed river. The station has two slot samplers with the pressure-pillow system (Birbeck-type) that allow a continuous measurement of bedload transport. The paper shows the bedload sampler operation, the load tests and the first results obtained. It is the first time that bedload transport is registered continuously in a river of the Iberian Peninsula.[Abstract] This article examines how snow plays a role in current erosive processes in a high mountain area (1800-2400 m a.s.l.) known as Peñalara, located in Spain's Central Range (40º 50' N; 3º 58' W). Snow depth and the movement of selected blocks at each site were recorded from October 1990 to June 1995. The relationship among late-lying snowpatches, geomorphologic heritage and current erosive processes was deternúned

Graphene-coated holey metal films: tunable molecular sensing by surface plasmon resonance

We report on the enhancement of surface plasmon resonances in a holey bidimensional grating of subwavelength size, drilled in a gold thin film coated by a graphene sheet. The enhancement originates from the coupling between charge carriers in graphene and gold surface plasmons. The main plasmon resonance peak is located around 1.5 microns. A lower constraint on the gold-induced doping concentration of graphene is specified and the interest of this architecture for molecular sensing is also highlighted.Comment: 5 pages, 4 figures, Final version. Published in Applied Physics Letter

The Fifth International Little Owl Symposium, 4–6 February 2011, Vic, Catalonia (Spain)

The First International Little Owl Symposium took place in Champ–sur–Marne (France) in November 2000, organized by the International little owl Working Group (ILOWG). It was the first international meeting regarding a sole owl species in Europe. Since then, efforts have been made to improve our knowledge and develop management plans for little owl conservation, and every new advance has been shared among all of us, owl researchers and owl friends, at regular international meetings. The Fifth Symposium gave continuity to the series of previous meetings held in France, England and Belgium. The most recent meeting was held in Herzele, Flanders, and the highlight was the presentation of the latest little owl monograph of Van Nieuwenhuyse et al., 2008. This meeting demonstrated the need to promote future gatherings of researchers.The First International Little Owl Symposium took place in Champ–sur–Marne (France) in November 2000, organized by the International little owl Working Group (ILOWG). It was the first international meeting regarding a sole owl species in Europe. Since then, efforts have been made to improve our knowledge and develop management plans for little owl conservation, and every new advance has been shared among all of us, owl researchers and owl friends, at regular international meetings. The Fifth Symposium gave continuity to the series of previous meetings held in France, England and Belgium. The most recent meeting was held in Herzele, Flanders, and the highlight was the presentation of the latest little owl monograph of Van Nieuwenhuyse et al., 2008. This meeting demonstrated the need to promote future gatherings of researchers.The First International Little Owl Symposium took place in Champ–sur–Marne (France) in November 2000, organized by the International little owl Working Group (ILOWG). It was the first international meeting regarding a sole owl species in Europe. Since then, efforts have been made to improve our knowledge and develop management plans for little owl conservation, and every new advance has been shared among all of us, owl researchers and owl friends, at regular international meetings. The Fifth Symposium gave continuity to the series of previous meetings held in France, England and Belgium. The most recent meeting was held in Herzele, Flanders, and the highlight was the presentation of the latest little owl monograph of Van Nieuwenhuyse et al., 2008. This meeting demonstrated the need to promote future gatherings of researchers

Possibilities of recovery for different digested sewage sludges

La legislación actual en la Unión Europea recomienda que los lodos de depuradora de aguas residuales se utilicen como fertilizante. Sin embargo, la presencia de metales pesados puede limitar esta aplicación, lo cual es más probable en caso de lodos de aguas residuales industriales. Por lo tanto, una segunda opción es la recuperación energética de los lodos. En el presente trabajo, se han analizado lodos digeridos procedentes de siete distintas depuradoras de aguas residuales españolas y se ha estudiado su viabilidad para usarse como fertilizantes, como combustible derivado de residuos o ser enviados a vertedero. Para determinar el poder fertilizante se ha realizado el análisis elemental (C, H, O, N y S) además del contenido en carbono orgánico asimilable, metales pesados, PO4 y potasio. El poder calorífico (Poder Calorífico Inferior) y el contenido en cenizas se han determinado también para evaluar la posibilidad de recuperación energética. Además, conocer el contenido en metales pesados, Cl, F, C, N y S es fundamental para estimar las emisiones atmosféricas generadas durante su incineración. Por otro lado, se incluye una comparación de estos lodos con otros tipos de combustiblesThe current European legislation regarding digested sludge from wastewater treatment plants recommends its use as a fertilizer. The presence of heavy metals, however, may limit this application and this clearly becomes even more important in the case of industrial wastewater treatment plants. Therefore, another option is the recovery of energy from the sludge. In this work, digested sludge coming from seven different wastewater treatment plants belong to an industrial estate in Spain are analysed. These sludges, either separately or altogether, can be used as fertilizers or refuse-derived fuel or sent to a landfill. In order to determine the fertilizing power, an elementary analysis (C, H, O, N and S) was conducted to establish the content in readily assimilated organic carbon, heavy metals, PO4 and potassium. The calorific value (lower heating value) and the ash content must be known in order to assess the possibility of energy recovery. Furthermore, analysis of heavy metal, Cl, F, C, N and S content is compulsory to be able to estimate atmospheric emissions generated during their incineration. A comparison of the sludges with other sorts of fuels is also provide

Influencia de las variables climáticas y socio-económicas en la generación de residuos urbanos en España

This paper analyses the generation of household waste in Spanish towns and cities with more than 5000 inhabitants. Data were obtained from questionnaires sent out to 216 town councils that were selected at random and from a previous study. The total composition of the household waste and the values of the annual generation rate of the total amounts of urban waste (AGRuw) were calculated using 53 % of the towns and cities in the sample. Additionally, variables concerning the size of the towns and cities, the climatic zones and the tourist areas were also defined in order to determine whether there were any significant differences as regards the generation of waste according to those variables. Results of comparisons revealed that the size of the town or city was the only variable that did not have an effect on the AGRuw. Linear regression models were also calculated in order to model the generation of urban wastes according to the socioeconomic variables (foreigners, unemployment and people/car) by zones. Find- ings showed that the model with the best fit was the one related to the touristic area.En este estudio se analiza la generación de los residuos domiciliarios en las ciudades españolas mayores de 5000 habitantes. Los datos se han obtenido mediante cuestio- narios enviados a 216 ayuntamientos seleccionados aleatoriamente y mediante un estudio anterior. Con el 53 % de las ciudades de la muestra se ha calculado la tasa de generación anual del total de los residuos urbanos (TGAru). Además se han definido variables relativas al tamaño de los municipios, las zonas climáticas y las zonas turís- ticas para determinar si existen diferencias significativas en cuanto a la generación de los residuos según dichas variables. Con los contrastes realizados se ha obtenido que el tamaño del municipio es la única variable que no influye en la TGAru. También se han calculado modelos de regresión lineal para modelizar la generación de residuos urbanos en función de variables socioeconómicas (extranjeros, desempleados y hab/ coche) en cada una de las zonas consideradas. Con ello se ha obtenido que el modelo que da mejor ajuste es el relativo a la zona turística

Actitud ante la recolección selectiva de biorresiduos

El objetivo de este estudio es analizar el grado de aceptación de la recolección selectiva de los biorresiduos en un municipio español donde ya se recoge en forma selectiva las fracciones de papel/cartón, vidrio y envases ligeros. Para ello, se ha diseñado un cuestionario basado en la metodología de valoración contingente y estructurado en las siguientes partes: descripción del bien que se pretende valorar, valoración del bien e información sobre la persona entrevistada. Se realizaron 400 entrevistas telefónicas, garantizando el nivel de confianza de 95.5 % y un error máximo del 5 %. Además de obtener información sobre los hábitos de separación en origen de las fracciones que actualmente se recogen en forma selectiva en el municipio, se obtuvo que más del 80 % de los entrevistados estaría dispuesto a separar también en origen los biorresiduos, y que el 40 % estaría dispuesto a pagar algo más en la tasa de recolección de residuos si fuera necesario.The aim of this research is to analyze the level of acceptance of the separate collection of bio-wastes in a Spanish municipality where paper/cardboard, glass and light packag- ing fractions are already collected separately. For that, a survey based on contingent valuation has been designed. The survey has been structured in the following parts: description of the specific good to value, valuation of the good and information about the surveyed person. Four hundred telephone interviews were performed, guaranteeing 95.5 % of confidence level and a maxim error of 5 %. As well as obtaining informa- tion about the separation in origin habits of the fractions which are already collected separately in the municipality, we obtained that 80 % of the surveyed population would be willing to separate in origin also bio-waste, and that 40 % would be willing to pay an increase in the waste collection tax if it were necessary

Numerical simulations of stellar SiO maser variability. Investigation of the effect of shocks

A stellar hydrodynamic pulsation model has been combined with a SiO maser model in an attempt to calculate the temporal variability of SiO maser emission in the circumstellar envelope (CE) of a model AGB star. This study investigates whether the variations in local physical conditions brought about by shocks are the predominant contributing factor to SiO maser variability because, in this work, the radiative part of the pump is constant. We find that some aspects of the variability are not consistent with a pump provided by shock-enhanced collisions alone. In these simulations, gas parcels of relatively enhanced SiO abundance are distributed in a model CE by a Monte Carlo method, at a single epoch of the stellar cycle. From this epoch on, Lagrangian motions of individual parcels are calculated according to the velocity fields encountered in the model CE during the stellar pulsation cycle. The potentially masing gas parcels therefore experience different densities and temperatures, and have varying line-of-sight velocity gradients throughout the stellar cycle, which may or may not be suitable to produce maser emission. At each epoch (separated by 16.6 days), emission lines from the parcels are combined to produce synthetic spectra and VLBI-type images. We report here the results for v=1, J=1-0 (43-GHz) and J=2-1 (86-GHz) masers.Comment: 16 pages, 8 figures, accepted by A&

Biometanización a partir de lodos de EDAR y rechazos de planta de compostaje

La mezcla de rechazos procedentes de plantas de compostaje y de lodos de EDAR urbanas se plantea como una alternativa para la valorización de estos residuos mediante su biometanización. Con ello se puede obtener un último beneficio de unos residuos que, de otra forma, irían a parar a vertedero. El rendimiento energético de esta valorización es aceptable y el residuo resultante de la digestión anaerobia podría, después de secarse, ser empleado como fertilizante o incinerado. En cualquier caso, la aplicación de este proceso a plantas de compostaje y a estaciones depuradoras de aguas residuales sólo sería rentable si se disminuyen y optimizan las distancias entre los lugares de generación y las instalaciones de biometanizaciónMixing reject material from composting plants and sludge from urban sewage treatment facilities is proposed as an alternative method for energy recovery from this waste by means of biomethanation. The aim of this process is to be able to extract one last benefit from waste that would otherwise end up in a sanitary landfill. The energy efficiency of this recovery is acceptable and the waste material resulting from the anaerobic digestion could, after drying, be used as a fertiliser or incinerated. In any case, applying this process to composting plants and to sewage treatment facilities would only be cost-effective if the distances between the points where the waste is generated and the biomethanation facilities are reduced and optimise