Search results for " medio ambiente"
showing 10 items of 967 documents
New insights in the metabolic behaviour of PAO under negligible poly-P reserves
2017
[EN] In a previous study the authors confirmed the ability of PAOs to perform GAO metabolism in short-term experiments. However, what happens when PAOs are exposed to poly-P shortage for an extended period of time? The answer to this question was the aim of this work from a macroscopic and microscopic point of view. Therefore, the poly-P was removed from a PAO enriched SBR and maintained without poly-P during five solid retention time. The PAOs were found to quickly change their metabolism to a clear GAO performance and remained without GAO colonization for the entire experimental period, even though GAO was present (around 5%) at the beginning of the experiment. Unlike the results obtained…
Mixed microalgae culture for ammonium removal in the absence of phosphorus: Effect of phosphorus supplementation and process modeling
2014
Microalgal growth and ammonium removal in a P-free medium have been studied in two batch photobioreactors seeded with a mixed microalgal culture and operated for 46 days. A significant amount of ammonium (106 mg NH4-Nl(-1)) was removed in a P-free medium, showing that microalgal growth and phosphorus uptake are independent processes. The ammonium removal rate decreased during the experiment, partly due to a decrease in the cellular phosphorus content. After a single phosphate addition in the medium of one of the reactors, intracellular phosphorus content of the corresponding microalgal culture rapidly increased, and so did the ammonium removal rate. These results show how the amount of phos…
Microalgae cultivation in wastewater: nutrient removal from anaerobic membrane bioreactor effluent
2012
This study investigated the removal of nitrogen and phosphorus from the effluent of a submerged anaerobic membrane bioreactor (SAnMBR) by means of a lab-scale photobioreactor in which algae biomass was cultured in a semi-continuous mode for a period of 42 days. Solids retention time was 2 days and a stable pH value in the system was maintained by adding CO2. Nitrogen and phosphorus concentrations in the SAnMBR effluent fluctuated according to the operating performance of the bioreactor and the properties of its actual wastewater load. Despite these variations, the anaerobic effluent proved to be a suitable growth medium for microalgae (mean biomass productivity was 234 mgl(-1) d(-1)), achie…
La educación ambiental en las Agendas 21 Locales de la provincia de Valencia
2017
La Educación Ambiental nació con la vocación de colaborar en la mejora ambiental, para ello, es de suma importancia incorporarla en los procesos de participación ciudadana de las Agendas 21. Consecuentemente se hace necesaria la planificación de la Educación Ambien tal Municipal mediante planes y programas en las Agendas 21 Locales. En este trabajo analizamos en qué medida se ha incorporado la Educación Ambiental en la Red de M unicipios firmantes de la Carta de Xàtiva en la Provincia de Valencia. Para la recolección de datos se utilizó el cuestionario estructurado que fue enviado a los 213 municipios firmantes de dicho documento. Los resultados obtenidos nos permiten afirmar que son escaso…
Correlación entre las temperaturas y las precipitaciones de las estaciones meteorológicas de Valencia-Viveros y la Devesa de l'Albufera
1990
Se realiza una comparación de las estaciones meteorológicas ubicadas en la Devesa de l'Albufera y Valencia-Viveros para el período comprendido entre agosto (1986), mes y año de inicio de los registros de la primera estación, y diciembre (1990). El estudio climático ha demostrado que ambas estaciones pertenecen a la misma subregión fitoclimática (IV3), correspondiendo a un clima mediterráneo: C4s4 -Devesay C2s2 -Valencia-. Bioclimáticamente quedan incluidas en el piso de vegetación Termomediterráneo cálido de ombroclima Seco. El análisis de correlación de las temperaturas (máximas, mínimas, medias) y precipitaciones mensuales ha resultado altamente significativo (? =0,001). Por otro lado, co…
P-recovery in a pilot-scale struvite crystallisation reactor for source separated urine systems using seawater and magnesium chloride as magnesium so…
2019
[EN] Practical recovery of a non-renewable nutrient, such as phosphorus (P), is essential to support modern agriculture in the near future. The high P content of urine, makes it an attractive source for practicing the recovery of this crucial nutrient. This paper presents the experimental results at pilot-plant scale of struvite crystallisation from a source-separated urine stream using two different magnesium sources, namely magnesium chloride and seawater. The latter was chosen as sustainable option to perform P-recovery in coastal areas. Real seawater was used to assess in a more realistic way its efficiency to precipitate P as struvite, since its composition (with noticeable concentrati…
El consumo de productos petrolíferos en el País Valenciano
1981
Evolution of small-scale magnetic elements in the vicinity of granular-size swirl convective motions
2014
Advances in solar instrumentation have led to a widespread usage of time series to study the dynamics of solar features, specially at small spatial scales and at very fast cadences. Physical processes at such scales are determinant as building blocks for many others occurring from the lower to the upper layers of the solar atmosphere and beyond, ultimately for understanding the bigger picture of solar activity. Ground-based (SST) and space-borne (Hinode) high-resolution solar data are analyzed in a quiet Sun region displaying negative polarity small-scale magnetic concentrations and a cluster of bright points observed in G-band and Ca II H images. The studied region is characterized by the …
A new Aphid genus and species (Hemiptera: Aphididae: Macrosiphini) living on ferns in Costa Rica and Mexico
2013
AbstractAphid species colonising ferns belong to the subfamily Aphidinae (Hemiptera: Aphididae) and the majority of these to the tribe Macrosiphini. A new genus in this tribe and its type species: Gibbomyzus pteridophytorumnew genus, new species, are established. Apterous and alate viviparous females are described from specimens collected on Blechnum buchtienii Rosenstock (Blechnaceae) in Costa Rica and on Pteridium aquilinum (Linnaeus) Kuhn (Dennstaedtiaceae) and an unidentified fern in Mexico. The taxonomic validity of the two new taxa is discussed based on morphological and molecular data. Morphologically, the new genus is compared with genera with swollen siphunculi recorded in the New …
Geografía: espacio social e imágenes de marca : el análisis de "Flor de mayo" de Vicente Blasco Ibáñez
1988
A TRAVES DE UN ANALISIS MINUCIOSO DE LA OBRA DEL NOVELISTA VALENCIANO VICENTE BLASCO IBAÑEZ (1867-1928), "FLOR DE MAYO", PODEMOS RECONSTRUIR EL ESPACIO VIVIDO DE LOS HABITANTES DEL CABANYAL DE PRINCIPIOS DE SIGLO. LA ACCION DE LA NOVELA, QUE FUE ESCRITA EN 1895, RECOGE LAS FORMAS DE VIDA DE LOS MARINEROS Y PESCADORES VALENCIANOS, EN SUS DIFERENTES ESPACIOS OPERATIVOS: EL ESPACIO DE LA PESCA, EL ESPACIO DEL CONTRABANDO, EL PROPIO PUEBLO DEL CABANYAL, LA CIUDAD DE VALENCIA, ARGEL, AFRICA, EL MEDITERRANEO. BLASCO IBAÑEZ RECOGIO CON VERACIDAD LOS ESPACIOS DE ACCION DE SUS PERSONAJES Y, GRACIAS A SU POPULARIDAD, HA CONTRIBUIDO A CREAR Y RECREAR ENTRE SUS LECTORES, LAS "IMAGENES DE MARCA" DE LUGA…