14 research outputs found

    Organic matter accumulation during the Holocene in the Guadalquivir marshlands (SW Spain)

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    The distribution of biomarker compounds and magnetic susceptibility observed in the sediment from a 20 m core drilled in the marshlands of the estuarine region of the Guadalquivir River (southwest coast of Spain) has allowed us to reconstruct the palaeoenvironmental evolution of this area during the Holocene. Several organic compounds (n-alkanes, ra-ketones, n-alkanols, n-alkanoic acids and organic sulphur), as well as different biomarker ratios, have been used to show changing environmental conditions through time. These geochemical proxies suggest good preservation of the organic matter, although some diagenesis has occurred to particular organic compounds, especially the n-alkanoic acids. Our data indicate a major allochthonous supply of terrestrial plants, with less influence from aquatic plants or algae through the core. There are markedly different palaeoenvironmental conditions between the uppermost 5 m (last 6ka cal. B.P.) and the rest of the core. From 5 m (ca 6ka cal. B.P.) to 19 m (ca 8ka cal. B.P.) depth the palaeoenvironmental conditions were almost constant. Based on organic sulphur content and n-alkane content logs, anoxic conditions prevailed from 8 to 6ka cal. B.P., while oxic conditions with enhanced convection of water (prevalence of fluvial input), and consequently a greater organic matter supply, predominated in the upper 5 m of the core. Similarly, little variation in the magnetic susceptibility profile below 5 m indicates stable environmental conditions, while in the upper 5 m conditions shifted to one with elevated water input and clastic sediment supply. This is linked to palaeofloral alterations in the Guadiamar/Guadalquivir drainage basins and/or anthropogenic effects. We propose that from ca 8 to 6 ka cal. B.P. a stable landscape physiognomy in the surroundings of the estuarine area of the Guadalquivir River, with a predominance of pines and grassland. However, over the last 6ka cal. B.P. a variation in the terrestrial plant biomarker compounds suggests an alternation of relatively dry and humid phases and/or the impact of human populations on altering the vegetation community have occurred

    Reconstrucci贸n paleoclim谩tica y paleoambiental de la Pen铆nsula Ib茅rica durante el Cuaternario, aplicaci贸n de modelos geoprospectivos para la evaluaci贸n de escenarios futuros

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    Esta comunicaci贸n trata de resumir el trabajo realizado por el ITGE, BRGM, CCMA, IPE, ETSIMM y ENRESA en el proyecto titulado "Paleoclimatological Revision of Climate Evolution and Environment in Western Mediterranean Region. Evaluation of future evolution scenarios in the Iberian Peninsula", en el marco del Programa de la Comisi贸n de las Comunidades Europeas sobre Gesti贸n y Almacenamiento de Residuos Radioactivos (contrato CEC FI2WCT91- 0075)

    Aportaciones al conocimiento de la evoluci贸n paleoclim谩tica y paleoambiental en la Pen铆nsula Ib茅rica durante los dos ultimos millones de a帽os a partir del estudio de trasvertinos y espeleotemas

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    En este trabajo se contemplan los resultados principales del Proyecto" Reconstrucci贸n Paleoclim谩tica desde el Pleistoceno Medio a partir de an谩lisis geocronol贸gicos e isot贸picos de travertinos espa帽oles" (P. CEC FI2W-CT91-0075 " Paleoclimatological revision of climate evolution in the Western Mediterranean Region, Evaluation of altered scenarios) . Se seleccionaron cuatro 谩reas de dep贸sitos travert铆nicos de car谩cter fluvial (Priego, R铆o Blanco), lacustre (R铆o Blanco, Banyoles) y aluvial (Tolox) as铆 como una zona con dep贸sitos espeleot茅micos (Karst de la Cueva del Reguerillo). En ellas se obtuvieron datos sobre la evoluci贸n del paisaje y del clima, los travertinos y espeleotemas son indicadores de clima c谩lido s.l. que de forma abreviada son: O Mediante la geomorfolog铆a y dataciones (paleomagnetismo, U/Th, Resonancia de esp铆n Resumen electr贸nico y racemizaci贸n de amino谩cidos), se determin贸 las historia fluvial de los travertinos de Priego y R铆o Blanco as铆 como del Karst de la Cueva del Reguerillo donde, adem谩s, se dataron un paleosismo y fen贸menos de neotect贸nica. La data m谩s antigua obtenida mediante Resonancia de esp铆n electr贸nico fue 950ka, mientras que mediante racemizaci贸n de amino谩cidos se dataron dep贸sitos de m谩s de 750ka. Mediante dataciones, sedimentolog铆a, an谩lisis de is贸topos estables y palinolog铆a se determinaron aspectos de la evoluci贸n clim谩tica de algunas 谩reas de la Pen铆nsula Ib茅rica. La correlaci贸n entre palinolog铆a e isotop铆a permiti贸 la validaci贸n de algunos de los resultados. Tambi茅n se obtuvieron datos cualitativos sobre input hidra煤licos a los sistemas fluviales o k谩rsticos

    Ordenaci贸n minero-ambiental de recursos de rocas industriales : aplicaci贸n a la reserva estatal de pizarras de la Cabrera (Le贸n)

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    La tesis tiene como objetivo principal el dise帽o de una metodolog铆a general, soportada y gestionada en Sistemas de Informaci贸n Geogr谩fica (SIG), para la realizaci贸n de Mapas de Ordenaci贸n Minero - Ambiental de los recursos de rocas y minerales industriales. Para el dise帽o y puesta a punto de esta metodolog铆a se ha realizado un estudio piloto de investigaci贸n metodol贸gica en el Reserva Estatal de pizarras de La Cabrera (Le贸n), que ha tenido como resultado primario y directo la realizaci贸n del "Mapa de Ordenaci贸n Minero - Ambiental del Yacimiento de Pizarras de La Cabrera (Le贸n). Este estudio piloto se inicia con un cap铆tulo donde se describe el inventario ambiental de la comarca natural de La Cabrera, donde se analizan los diferentes elementos que constituyen el medio, tanto f铆sico como socio socioec贸mico y cultural; a continuaci贸n sigue un cap铆tulo dedicado a la explotaci贸n minera de la pizarra. Se aborda a continuaci贸n el estudio de Diagn贸stico Territorial, cuyo objetivo es el an谩lisis de la capacidad de acogida del territorio de La Cabrera parala explotaci贸n de sus recursos de pizarra, mediante la definici贸n de un modelo impacto/aptitud. Para las evaluaci贸n del valor para la conservaci贸n, del impacto, y de la aptitud para la explotaci贸n mionera de cada una unidad territorial se ha dise帽ado un m茅todo basado en la desagradaci贸n en componentes, y obtenci贸n de los valores agregados mediante la asignaci贸n de coeficientes de ponderaci贸n a cada componente. El an谩lisis de la capacidad de acogida del territorio para la actividad minera se basa en el establecimiento de un modelo de impacto/aptitud, en el cual, sobre una matriz de doble entrada (rangos de impacto y rangos de aptitud), se definen las clases de capacidad de acogida. El Mapa de Ordenaci贸n Minero - Ambiental se obtiene a partir de una zonificaci贸n del territorio basada en la capacidad de acogida y en la aplicaci贸n de criterios excluyentes y condicionantes para la actividad minera. Este mapa zonifica el territorio soporte de los recursos de pizarra en tres categor铆as de ordenaci贸n: zonas de protecci贸n ambiental, donde no sea recomendable la ezplotaci贸n minera, y zonas explotables con dos niveles con dos niveles de prioridad

    Waste-to-Energy Process to Recover Dangerous Pollutants in an Environmental Protected Area

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    The present study aims to extract the polluting material from a lagoon and use it as an alternative fuel in cement industries. To this end, in the methodology will analyze two alternatives for the waste: fuel generation and incineration. The polluting material from the Arganda lagoon has highly calorific value to be used as fuel. Thus, not only are these wastes used, but also an area with potentially hazardous waste is decontaminated. After the extraction, which due to the characteristics of the material is chosen for the novel pumping extraction, and subsequent generation of fuel, the process for using this waste is through the distribution of the created fuel to nine cement plants in Spain, leading to significant environmental benefits. The results of the process shows an energy efficiency of 97% for using the waste as fuel, and a consumed energy of approximately 6000 kWh/t路waste to the process that leads to the desired environmental benefit. The use of waste contributes to the reduction of CO2 emissions and a decrease in the use of fossil fuels

    Correlation between mRNA levels and functional role of 1-adrenoceptor subtypes in arteries: evidence of 1L as a functional isoform of the 1A-adrenoceptor

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    10 pages, 3 figures, 10 tables.-- PMID: 15951348 [PubMed]The mRNA levels for the three alpha1-adrenoceptor subtypes, alpha1A, alpha1B, and alpha1D, were quantified by real-time RT-PCR in arteries from Wistar rats. The alpha1D-adrenoceptor was prominent in both aorta (79.0%) and mesenteric artery (68.7%), alpha1A predominated in tail (61.7%) and small mesenteric artery (73.3%), and both alpha1A- and alpha1D-subtypes were expressed at similar levels in iliac artery. The mRNA levels of the alpha1B-subtype were a minority in all vessels (1.7-11.1%). Concentration-response curves of contraction in response to phenylephrine or relaxation in response to alpha1-adrenoceptor antagonists on maximal sustained contraction induced by phenylephrine were constructed from control vessels and vessels pretreated with 100 micromol/l chloroethylclonidine (CEC) for 30 min. The significant decrease in the phenylephrine potency observed after CEC treatment together with the inhibitory potency displayed by 8-{2-[4-(2-methoxyphenyl)-1-piperazinyl]-8-azaspiro (4,5) decane-7-dionedihydrochloride} (BMY-7378, an alpha1D-adrenoceptor antagonist) confirm the relevant role of alpha1D-adrenoceptors in aorta and iliac and proximal mesenteric arteries. The potency of 5-methylurapidil (an alpha1A-adrenoceptor antagonist) and the changes in the potency of both BMY-7378 and 5-methylurapidil after CEC treatment provided evidence of a mixed population of alpha1A- and alpha1D-adrenoceptors in iliac and distal mesenteric arteries. The low potency of prazosin (pIC50 < 9) as well as the high 5-methylurapidil potency in tail and small mesenteric arteries suggest the main role of alpha1A/alpha1L-adrenoceptors with minor participation of the alpha1D-subtype. The mRNA levels and CEC treatment corroborated this pattern and confirmed that the alpha1L-adrenoceptor could be a functional isoform of the alpha1A-subtype.This work was supported by a research grant from the Spanish Comisi贸n Interministerial de Ciencia y Tecnolog铆a (SAF2001-2656). Daniel Mart铆 Canet received a fellowship from Universidad Cardenal Herrera-CEU.Peer reviewe
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