150 research outputs found

    Decoloración y detoxificación de aguas de alperujo mediante el empleo de esmectitas e hidrotalcita

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    2 páginas.-- 1 figura.-- 1 tablas.-- 8 referencias.-- Poster presentado en XXIV Reunión de la Sociedad Española de Arcillas Sevilla. Libro de Resúmenes: Noviembre de 2015 en Sevilla.El alperujo es el residuo sólido del proceso de extracción de aceite de oliva virgen en dos fases, que se produce en grandes cantidades en diversas regiones españolas y cuyo empleo como fertilizante y enmendante de suelos, una vez compostado, facilita una salida sostenible para estos contribuyendo favorablemente al secuestro de carbono (1,2) No obstante también puede dar lugar a algunos efectos adversos: a) Coloración de las aguas, b) Deterioro del suelo por su acidez y sales, c) Solubilización, transporte y lixiviación de algunos metales pesados y plaguicidas (3, 4) y d) Fitotoxicidad sobre plantas y microrganismos acuáticos, si no han sido previamente compostados o tratados (5). Sobre la hipótesis del conocido potencial de los materiales arcillosos de interaccionar con la materia orgánica soluble (MOS) de suelos, sedimentos o residuos (4, 6), el objetivo del presente trabajo ha sido evaluarla capacidad de arcillas catiónicas y aniónicas como adsorbentes de la MOS procedente de alperujo, responsable de los efectos adversos descritos. La finalidad última es el posible desarrollo y utilidad de adsorbentes naturales para reducir la coloración y toxicidad de aguas de lavado de almazaras, o para su posible co-aplicación con alperujo a suelos agrícolas disminuyendo los efectos adversos sobre semillas o plantas o para corregir los efectos de un vertido puntual incontrolado.Este trabajo ha sido financiado a través de los proyectos P07-AGR-03077 y P11-AGR-07400 y AGR-264 de la Junta de Andalucía, cofinanciados por FEDER y FSE; y el Convenio RECUPERA 2020 del MINECO-CSIC.Peer reviewe

    Enantioselective behavior of metalaxyl in soil under repeated applications

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    10 páginas.-- 5 imágenes.-- 2 tablas.-- 52 referenciasBACKGROUND: Soil incubation and column leaching experiments were conducted to address the question of whether the type of formulation (unsupported versus clay supported) and repeated applications of the chiral fungicide (RS)-metalaxyl affected the enantioselectivity of its dissipation and leaching in a slightly alkaline, loamy sand agricultural soil. RESULTS: Regardless of the type of formulation and the number of fungicide applications, the R-enantiomer of metalaxyl was degraded faster than the S-enantiomer, but the individual degradation rates of R- and S-metalaxyl were highly affected by the different application regimes assayed (t1/2 = 2-104 days). Repeated applications accelerated the degradation of the biologically active R-metalaxyl enantiomer, whereas they led to slower degradation of the non-active S-metalaxyl enantiomer. The type of formulation had less influence on the dissipation rates of the enantiomers. For all formulations tested, soil column leachates became increasingly enriched in S-enantiomer as the number of fungicide applications was increased, and application of metalaxyl to soil columns as clay-based formulations reduced the leaching of both enantiomers. CONCLUSION: Pesticide application conditions can greatly influence the enantioselective dissipation of chiral pesticides in soil, and hence are expected to exert a great impact on both the biological efficacy and the environmental chiral signatures of pesticides applied as mixtures of enantiomers or racemates to agricultural soils. © 2015 Society of Chemical Industry.This work has been financed by the Spanish Ministry of Economy and Competitiveness (MINECO Project AGL2011-23779) and Junta de Andalucía (Research Group AGR-264), cofinanced by European FEDER-FSE funds (Operative Programme 2007-2013). Beatriz Gámiz thanks the Junta de Andalucía for a post-doctoral contract linked to the project P07-AGR-03077. María Adelino thanks MINECO for a predoctoral FPI fellowship. The authors also thank MJ Calderón (IRNAS, CSIC),MI Cardo (IRNAS, CSIC) and P Franco (Chiral Technologies Europe) for technical assistance, and Dr. S Redondo and Dr. E Mateos (University of Seville) for their help with the statistical treatment of the data.Peer reviewe

    Assessing the Effect of Organoclays and Biochar on the Fate of Abscisic Acid in Soil

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    10 páginas.-- 6 figuras.-- 2 tablas.-- 56 referencias.-- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jafc.6b03668The potential use of allelopathic and signaling compounds as environmentally friendly agrochemicals is a subject of increasing interest, but the fate of these compounds once they reach the soil environment is poorly understood. This work studied how the sorption, persistence, and leaching of the two enantiomers of the phytohormone abscisic acid (ABA) in agricultural soil was affected by the amendments of two organoclays (SA-HDTMA and Cloi10) and a biochar derived from apple wood (BC). In conventional 24-h batch sorption experiments, higher affinity toward ABA enantiomers was displayed by SA-HDTMA followed by Cloi10 and then BC. Desorption could be ascertained only in BC, where ABA enantiomers presented difficulties to be desorbed. Dissipation of ABA in the soil was enantioselective with S-ABA being degraded more quickly than R-ABA, and followed the order unamended > Cloi10-amended > BC-amended > SA-HDTMA-amended soil for both enantiomers. Sorption determined during the incubation experiment indicated some loss of sorption capacity with time in organoclay-amended soil and increasing sorption in BC-amended soil, suggesting surface sorption mechanisms for organoclays and slow (potentially pore filling) kinetics in BC-amended soil. The leaching of ABA enantiomers was delayed after amendment of soil to an extent that depended on the amendment sorption capacity, and it was almost completely suppressed by addition of BC due to its irreversible sorption. Organoclays and BC affected differently the final behavior and enantioselectivity of ABA in soil as a consequence of dissimilar sorption capacities and alterations in sorption with time, which will affect the plant and microbial availability of endogenous and exogenous ABA in the rhizosphere.This work has been financed by the Spanish Ministry of Economy and Competitiveness (MINECO Project AGL2014- 51897-R), EU FACCE-JPI (Designchar4food Project), and Junta de Andalucıa (P011-AGR-7400 and Research Group ́ AGR-264), cofinanced with European FEDER funds. The use of trade, firm, or corporation names in this paper is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the U.S. Department of Agriculture, the Agricultural Research Service, or the Instituto de Recursos Naturales y Agrobiologıa de Sevilla ́ (IRNAS-CSIC) of any product or service to the exclusion of others that may be suitablePeer reviewe

    Effect of organic amendments on herbicide sorption as related to the nature of the dissolved organic matter

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    It has been assessed the influence of four organic amendments (OA) consisting of two commercial humic amendments (liquid LF and solid SF) from olive-mill wastes, a solid urban waste (SUW), and a sewage sludge (SS) on the sorption properties and leaching potential of simazine and 2,4-D. A sandy soil (TR) and a sandy-clay soil with a relatively high montmorillonite content (A) were treated with the diverse OA. Dissolved organic matter (DOM) was extracted from the amendments, the soils, and the amended soils and studied by fluorescence spectroscopy. A humification index (HIX) was calculated from the fluorescence data. Sorption was determined with the batch technique. Spectroscopical studies revealed that the DOM of the LF differs from the other OA by having a very low ability to absorb and to fluoresce and by its very low HIX values, which indicates that the LF contains large amounts of nonhumified material and consists of small molecules. On the other hand, the SF amendment contains the highest amounts of highly humified material and a large number of carboxylic groups. Amended soils sorbed simazine and 2,4-D to a greater extent than the untreated soils, except in the case of simazine sorption in the LF amended soil A, which had a lower simazine sorption than the original soil. The small molecules of DOM in the LF compete with simazine for montmorillonite sorption sites in soil A. This is not the case for 2,4-D, since this herbicide does not sorb on montmorillonite. In the case of the soil TR, with a lower montmorillonite content, there is no competition between simazine and the LF molecules for sorption sites. Soils amended with the highly humified SF were the best sorbents for simazine but not for 2,4-D, which can be attributed to repulsion between negatively charged 2,4-D molecules and COOgroups, which are more abundant in SF.This project has been supported by Junta de Andalucía through Research group 4092, CICYT through AMB96-0445- CO2-O2, the Deutsher Akademischer Austauschdienst and Ministerio de Educación y Cultura through Acciones Integradas HA98-0072, and by the European Science Foundation within its Groundwater Pollution Program (G-Poll). Municipal treatment plant EMASESA is also acknowledged for providing the sewage sludge.Peer Reviewe

    Localization Method for Autonomous Vehicles by using Vertical Elements in the Environment

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    The goal of this work is to provide autonomous cars with an alternative method to estimate their position in the world. It focuses on those situations when the GPS signal gets imprecise, weak or even lost due to environment conditions (long tunnels, dense forests, high buildings around, etc.). By installing two Velodyne VLP-16 LiDAR devices on the top of the car, located on both front corners of the vehicle structure, it is possible to acquire a 3D representation of this environment as a point cloud. This point cloud will be analyzed in order to find thin, vertical elements, such as traffic signals, traffic lights and so on. If these elements have been previously georeferenced, this is, their coordinates have been acquired and saved, the method will try to compare and match the incoming information from the environment to the georeferenced objects, i.e., performing data association. If the detected elements match any of the georeferenced ones, the car will correct an estimate of its position in a global frame.RoboCity2030-DIH-CM, Madrid Robotics Digital Innovation Hub, S2018/NMT-4331, funded by R&D Activities Program in Comunidad de Madrid and cofunded by EU Structural Funds.Peer reviewe

    Efecto de la coaplicación de herbicidas y adición de alperujo como enmienda en el comportamiento de diurón y terbutilazina en un suelo arcillo-limoso

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    Congreso celebrado del 21-24 de septiembre 2010, en Granada, España.Los herbicidas se aplican a los cultivos como formulaciones que habitualmente incluyen más de un principio activo. Sin embargo, los estudios sobre comportamiento de herbicidas en suelos en el laboratorio suelen hacerse aplicando los herbicidas de forma individual.Peer reviewe

    Nanohybrids of Mg/Al layered double hydroxide and long-chain (C18) unsaturated fatty acid anions: Structure and sorptive properties

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    10 páginas.-- 8 figuras.-- 1 tabla. 59 referencias.-- Appendix A. Supplementary data con 6 páginas (3 tablas y 2 figuras.-- Número espeical: Clay Science & Technology (XV International Clay Conference)Long-chain (C18) unsaturated fatty acid anions, elaidate (ELA), oleate (OLE), linoleate (LINO), and linolenate (LINOLEN), were intercalated into Mg/Al (3:1) layered double hydroxide (LDH) and the resultant organo-LDH nanohybrid materials were characterized and subsequently evaluated as sorbents of six pesticides (clopyralid, imazethapyr, diuron, atrazine, alachlor, and terbuthylazine). The effect of the degree (18:1, 18:2, 18:3) and type (cis/trans) of unsaturation in the fatty acid alkyl chain on both the structure and sorptive properties of the LDH-unsaturated fatty acid nanohybrids was determined. All fatty acid anions were readily intercalated into the LDH, yielding structures with basal spacing values ranging between 32 Å (LDH-LINOLEN) and 40 Å (LDHELA). The bend imposed by the cis geometry of the double bonds present in OLE, LINO and LINOLEN was identified as a major factor determining the arrangement of these anions in the LDH interlayer space. Intercalation of cis-unsaturated fatty acid anions led to less densely packed structures and reduced the interlayer distance of the resultant nanohybrid compared to the structures resulting from intercalation of the linear, trans-unsaturated elaidate anion. All organo-LDHs displayed higher affinity to uncharged pesticides as compared to unmodified LDH, but double bonds in the fatty acid alkyl chain, particularly when present in cis configuration, reduced the affinity of the organo-LDHs to all pesticides, presumably because they led to structures with reduced hydrophobicity as compared to those resulting from the incorporation of linear organic anions.This work has been financed by the Spanish Ministry of Economy and Competitiveness (MINECO Project AGL2011-23779) and Junta de Andalucía (JA Projects P07-AGR-03077 and P11-AGR-7400 and Research Group AGR-264), cofinanced with European FEDER-FSE funds (Operative Program 2007–2013). B. Gámiz thanks JA for a post-doctoral contract linked to the project P07-AGR-03077. M.A. Adelino thanks MINECO for her pre-doctoral FPI fellowship.Peer reviewe

    Microclimatic studies in Paranhos water galleries, Porto (Portugal)

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    Sanz Rubio, Enrique et al.-- 4 pages, 3 figures, 4 references.-- Proceedings of the International Congress on Science and Technology for the Conservation of Cultural Heritage, held 2-5 october, Santiago de Compostela, España.Paranhos constitutes one of the main water galleries excavated in the granite substratum of Porto City (Portugal) to gather the groundwater for public use during the past six centuries. The interest of this water gallery is double: a) Cultural Heritage and scientific value, b) Underground geoturism. A multidisciplinary research to study the microclimatology, geochemistry, mineralogy and geomicrobiology of the Paranhos catchwork galleries is currently in progress. The characterization of the main environmental parameters (air-rock temperature, relative humidity, CO2, 222Rn, etc.) in the internal atmosphere would allow the establishment of: a) Fluid-rock interactions and development of a physical-chemical model of air-water-rock, as a base to define their relations with unusual mineral formations and microbial communities b) Microclimatic parameters and determination of effective radioactive dose for visitors based on 222Rn studies, as potential use as underground geotourism site under safe conditions.This research was supported by the Spanish Project CGL2011-25690.Peer reviewe

    Die Wettbewerbsfähigkeit der arabischen Mittelmeerländer im internationalen Vergleich

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    6 p.- Papers presented at the International Workshop "The Conservation of Subterranean Cultural Heritage", held 25-27 March 2014, in Seville, Spain.Paranhos constitutes one of the main water galleries excavated in the granite substratum of Porto City (Portugal) to gather the groundwater for public use during the past five centuries. This gallery is a Subterranean Cultural Heritage site with a potential use for underground geotourism under safe conditions. An environmental monitoring programme has been conducte in the site comprising rapid multi-parameters. This programme has allowed the identification of urban-induced causes of contamination of the aquifer and internal tunnel atmosphere (waste-water and gas leakage). This study has also comprised the determination of effective radioactive dose in different sectors of the tunnel for potential visitors based on 222Rn studies.Financiado con el Proyecto (HAR-2010-11432-E) Red de Ciencia y Tecnología para la Conservación del Patrimonio CulturalPeer reviewe

    Effect of exogenous carbon on movement of simazine and 2,4-D in soils. Soil Sci

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    ABSTRACT stimulate soil microbial activity, which could potentially lead to accelerated degradation, reducing the total Topp et al., 1996
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