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Mine driven trace elements' pollution entails environmental risks and causes soil infertility. In the last decades, in situ techniques such as phytostabilization have become increasingly important as ways to tackle these negative impacts. The aim of this study was to test the individual and combined effects of different aided phytostabilization techniques using substrate from barren tailings of a Cu mine, characterized by extreme infertility (high acidity and deficiency of organic matter and nutrients). The experiment analyzed the growth of Populus nigra L. planted alone (P) or in co-cropping with Trifolium repens L. (PT), in pots containing mine soil amended with compost (1, 10, compost, soil, w/w) non inoculated (NI) or inoculated with plant growth promoting rhizobacteria (PGP), mycorrhizae (MYC) or a combination of bacterial and fungal inocula (PGPMYC). Non-amended, non-planted and non-inoculated reference ports were also prepared. Plants were harvested after 110 days of plant development and several biometric and phytopathological parameters (stem height, aerial biomass, root biomass, wilting, chlorosis, pest and death) and macro and micronutrient composition were determined. The growth substrate was analyzed for several physicochemical (pH, CECe, and exchangeable cations, total C and N, P Olsen and availability of trace elements) and microbiological (community level physiological profiles: activity, richness and diversity) parameters. The use of the amendment, P. nigra plantation, and inoculation with rhizobacteria were the best techniques to reduce toxicity and improve soil fertility, as well as to increase the plant survival and growth. Soil bacterial functional diversity was markedly influenced by the presence of plants and the inoculation with bacteria, which suggests that the presence of plant regulated the configuration of a microbial community in which the inoculated bacteria thrive comparatively better. The results of this study support the use of organ

Soils are complex and dynamic systems that perform essential functions contributing to the sustainability of terrestrial ecosystems and the support of life. They participate in a wide variety of ecosystem functions/services (e.g., Baveye et al., 2016), including those related to the production of biomass, the regulation of carbon and nutrient cycles, and the regulation of water resources and air quality, due to their filtering and buffering capacity.

Hexachlorocyclohexane (HCH) has been one of the most used pesticide from 1950 to early 2000 and has led to a current global soil pollution. HCH isomers are considered persistent organic pollutants (Stockholm Convention, 2009) and restoration of HCH-contaminated soils is urgently required. Bioremediation is one of the most promising remediation techniques and its effectiveness can be enhanced through the application of surfactants, which solubilize the contaminant, and hence increase its bioavailability. However, their application in situ is challenging due to their reported toxicity. In this context, we evaluated the micellar effect of a wide structurally diverse group of Surface- Active Ionic Liquids (SAILs) and conventional surfactants (non-ionic, cationic and anionic) on the modification of the apparent solubility of HCH in water. The synergistic effect of a combined system of a SAIL and a surfactant was verified using two blends with different SAIL/surfactant proportions. SAILs/surfactant solutions of different concentrations (>critical micelle concentration) were contaminated with HCH isomers (at a concentration ca. 10 times their solubility limit) and left under constant agitation until equilibrium (24 h). Then, the solubilized fraction of HCH isomers was analysed by GC/MS, and the solubility enhancement caused by SAILs/surfactants was calculated by normalization with a SAIL/surfactant-free control. Additionally, two ecotoxicological assessments were carried out: a) germination and early growth of Lolium perenne and Trifolium pratense; and b) inhibition of bacterial bioluminescence of Aliivibrio fischeri. HCH solubility enhancement varied depending on the concentration and the structure of SAILs/surfactants, inducing also different effects among individual isomers. In general, anionic compounds showed a higher effect on the solubilisation of HCH, reaching up to a ca. 7-fold increase with regard to the control. However, most of them were toxic to plants and/or

The application of an effective and sensitive analytical method to determine soil contaminants is a crucial step in monitoring and remediation processes. In the present work, we optimized the analysis of volatile organic compounds (VFOC) commonly present in fuel: oxygenates (FO-MTBE and ETBE-) and monoaromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene (BTEX). Headspace (HS) and headspace-solid phase microextraction (HS-SPME) were optimized in water samples, and validated for contaminated soils, using artificially spiked soils. Contaminants were identified and quantified by gas chromatography coupled to mass spectrometry (GC/MS). Matrix effect correction with surrogate standards resulted essential when analyzing soil samples, especially when the sample exerted a strong sorption on the contaminants, La aplicación de metodologías analíticas sensibles y efectivas para la determinación de los contaminantes del suelo es una etapa crucial para la realización de experimentos de monitorización y remediación. En el presente trabajo, se optimizó el análisis de compuestos orgánicos volátiles (VFOC) comúnmente presentes en combustibles: incluyendo compuestos oxigenados (FO-MTBE y ETBE-) e hidrocarburos monoaromáticos, tales como benceno, tolueno, etilbenceno y xileno (BTEX). Los métodos de extracción en headspace (HS) y microextracción en fase sólida en headspace (HS-SPME) fueron optimizados para aguas contaminadas y después validadas para suelos, utilizando muestras contaminadas de forma artificial. La corrección del efecto matriz con estándares tipo surrogate fue esencial para el análisis de muestras de suelos, especialmente para aquellas que ejercían una fuerte adsorción sobre los contaminantes, A aplicação de um método analítico eficaz e sensível para determinar contaminantes orgânicos do solo e da água é um passo essencial durante os processos de monitorização e recuperação ambiental. No presente trabalho optimizou-se a análise de alguns compostos orgânicos voláteis que surgem, usualmente, nos combustíveis: compostos oxigenados (FOMTBE e ETBE-) e hidrocarbonetos monoaromáticos tais como benzeno, tolueno, etilbenzeno e xileno (BTEX). As metodologias de extracção headspace (HS) e microextracção em fase sólida em modo headspace (HS-SPME) foram otimizadas em amostras de água e validadas para amostras de diferentes solos contaminados artificialmente. Os contaminantes orgânicos foram identificados e quantificados por cromatografia gasosa associada a espectrometria de massa (GC/MS). A correção do efeito da matriz com padrões surrogate foi essencial para a análise das amostras de solo, especialmente em solos que apresentavam uma forte adsorção dos contaminantes

The plant-microorganism-soil system of three pseudometallophytes (Betula celtiberica, Cytisus scoparius and Festuca rubra) growing in a Pb/Zn mine was characterised. Plant metal accumulation, soil metal fractions (rhizosphere and non-vegetated) and bacterial densities were determined. Total Cd, Pb and Zn in non-vegetated soils was up to 50, 3000 and 20,000 mg kg−1 dry weight, respectively. The residual fraction dominated non-vegetated soils, whereas plant-available fractions became important in rhizosphere soils. All plant species effectively excluded metals from the shoot. F. rubra presented a shoot:root transport factor of ≤0.2 and this population could be useful in future phytostabilisation trials. Culturable bacterial densities and diversity were low (predominantly Actinobacteria). Rhizosphere soils hosted higher total and metal-tolerant bacterial densities. Seventy-four metal-tolerant rhizobacteria were isolated, and characterised genotypically (BOX-PCR, 16S rDNA) and phenotypically [Cd/Zn tolerance, biosurfactant production and plant growth promoting (PGP) traits]. Several isolates resisted high concentrations of Cd and Zn, and only a few presented PGP traits. Fourteen isolates were evaluated for promoting plant growth of two species (Salix viminalis and Festuca pratensis). Thirteen inoculants enhanced growth of F. pratensis, while only three enhanced growth of S. viminalis. Growth enhancement could not always be related to isolate PGP traits. In conclusion, some isolates show potential application in phytostabilisation or phytoextraction techniques.

Bacterial strains were isolated from the rhizosphere of three populations of the Ni-hyperaccumulator Alyssum serpyllifolium subsp. lusitanicum (A. pintodasilvae; M, S, and L), one population of Ni-hyperaccumulator A. serpyllifolium subsp. malacitanum (A. malacitanum; SB), and one population of the non-hyperaccumulator A. serpyllifolium subsp. serpyllifolium (A. serpyllifolium; SN). Isolates were characterized genotypically by BOX-PCR genomic DNA fingerprinting and comparative sequence analysis of partial 16S rRNA gene, and phenotypically by their Ni tolerance (0–10 mM), presence of plant growth promoting traits (indoleacetic acid (IAA)-, siderophore-, or organic acid-production, and phosphate solubilization) or capacity to produce biosurfactants. Among the collection of rhizobacteria, 84 strains were selected (according to their BOX-PCR profiles and phenotypic characteristics) to assess their ability to modify Ni extractability from Ni-rich (serpentine) soils. Metabolites produced by 13 of the isolates mobilized soil Ni (originating from the rhizosphere of both Ni-hyperaccumulators and non-hyperaccumulator). In contrast, Ni extraction using culture medium filtrates which had supported the growth of 29 strains was significantly reduced. The remaining strains had no effect on Ni mobility. Bacterial induced Ni mobilization was not related to Ni resistance or the phenotypic traits tested. Isolates with potential use in phytoremediation techniques will be further studied in a plant-microorganism-soil system.

Mining activities are important sources of trace elements in the environment. Tailings resulting from this type of activity tend to present high concentrations of trace elements and host metal-tolerant plants and their associated microorganisms. These plant-microbial associations may be of potential use in phytoremediation techniques. In this study, individuals of three plant species (Betula, Cytisus, Festuca) growing in a Pb/Zn mine in Rubiais (NW Spain) were sampled. Whole plants and their adhering soil, and nonvegetated soil, were collected. Bulk and rhizosphere soils were analysed for physico-chemical properties (pH, organic C/N, TOC, CEC, total metal (Cd, Pb and Zn) content, metal fractionation) and microbiological characteristics. Plant tissues were analysed for total metal content. All species excluded metals from shoot tissues, and Betula was found growing in the more contaminated points (hot spots). Plant-available fractions of metals (including less mobile metals such as Pb) were significantly higher in the rhizosphere. The number of colony forming units was determined in bulk and rhizosphere soils on mineral medium without metals or supplemented with increasing concentrations of Cd or Zn (0.1 or 1.0 mM Cd, 1 mM or 3 mM Zn). As expected, rhizosphere soils host higher total bacterial densities but also a higher proportion of metal-tolerant bacteria compared to nonvegetated soil. Of the three species, Cytisus hosts the highest densities of metal tolerant rhizobacteria. Eighty bacterial strains were isolated from rhizosphere soils. These strains were characterized by BOX-PCR profiling and comparative sequence analysis of 16S rRNA genes and screened for their ability to produce IAA, siderophores, biosurfactants and organic acids, to solubilise phosphate and for their Zn and Cd tolerance. Potentially useful metal-resistant or plant-growth promoting rhizobacteria will be selected for further plant inoculation studies in phytoremediation trials.

In this study we determine culturable microbial densities (total heterotrophs, ammonifiers, amylolytics and cellulolytics) and bacterial resistance to Co, Cr, and Ni in bulk and rhizosphere soils of three populations of the Ni-hyperaccumulator Alyssum serpyllifolium subsp. lusitanicum and the excluder Dactylis glomerata from ultramafic sites (two populations in Northeast (NE) Portugal (Samil (S), Morais (M)) and one population in Northwest (NW) Spain (Melide (L)). The relationship between bioavailable metal concentrations (H2O-soluble) and microbial densities were analysed. Significant differences in microbial densities and metal-resistance were observed between the two species and their three populations. The hyperaccumulator showed higher microbial densities (except cellulolytics) and a greater rhizosphere effect, but this was only observed in S and M populations. These populations of A. serpyllifolium also showed selective enrichment of Ni-tolerant bacteria at the rhizosphere where Ni solubility was enhanced (densities of Ni-resistant bacteria were positively correlated with H2O-soluble Ni). These rhizobacteria could solubilise Ni in the soil and potentially improve phytoextraction strategies.

España es líder mundial en producción de pizarras de techar; la producción supera las 600.000 toneladas de pizarra de gran calidad, suponiendo mas de 300 millones euros. La aplicación de la pizarra con productos protectores permite comercializar placas más oxidables reduciendo escombreras y problemas ambientales. El presente protocolo sirve para evaluar estos nuevos productos protectores que empiezan a utilizarse en el sector pizarrero. Se propone una combinación de tres ensayos tecnológicos junto con un cuestionario visual para otorgar índices de calidad. Cada ensayo está orientado para clarificar una propiedad importante en el uso de la pizarra de techar: (i) Ciclo térmico para determinar el grado de oxidación de los sulfuros de hierro; (ii) Exposición al gas SO2 para conocer su comportamiento en ambientes urbanos ácidos; (iii) Exposición a la niebla salina y rayos UV para evaluar la eficacia de la capa protectora frente a la corrosión salina y la radiación solar. Los ensayos físico-químicos han sido realizados en el Centro Tecnológico de la Pizarra de Orense mientras que las caracterizaciones químico-estructurales de las pizarras naturales, impregnadas y alteradas fueron realizadas por difracción de rayos X y microscopias ópticas y electrónicas de barrido en la Universidad de Santiago de Compostela. Los análisis cuantitativos de los grados de alteración, se han realizado con software libre (IMAGEJ) a partir imágenes de placas de pizarra muy planas tomadas con un escáner. El protocolo se ha experimentado con muestras de los productos protectores de pizarra más importantes que actualmente son siloxanos, resinas orgánicas y poliuretanos.

[ES] La apertura de la mina de lignitos de As Pontes, prácticamente hasta su base, ha permitido estudiar con detalle la naturaleza y procesos de formación de un yacimiento Oligoceno-Miocénico con hasta 500 m de depósitos sedimentarios producidos durante unos 10-11 millones de años. El yacimiento está caracterizado por la alternancia de capas de carbón (lignitos, fundamentalmente lignito pardo) separadas por capas de sedimentos detríticos de textura variada. Dentro de esta secuencia se ha podido comprobar que la formación del carbón se ha producido mayoritariamente en un ambiente pantanoso, con vegetación dominada por géneros como Thypha y Juncus, que se desarrollaron en suelos hidromorfos, fundamentalmente Gleisoles e Histosoles. En condiciones de pH próximas a la neutralidad y ambiente anóxico-subóxico en el que el Fe se reduce al estado ferroso, dando origen a la formación de nódulos y concreciones de siderita y sulfuros biogénicos. La siderita, aparece claramente asociada a la rizosfera de macrófi tos acuáticos dentro de antiguos horizontes gleicos, con segregación y movilización de Fe (Bg y Cg o Cr) teniendo la respiración de las raíces una clara relación con la formación del mineral. Estos suelos tenían horizontes superfi ciales muy ricos en materia orgánica (H Hísticos o A móllicos o úmbricos) que, posteriormente fueron fosilizados por aportes torrenciales ricos en materiales caoliníticos derivados de suelos bien drenados (probablemente suelos ferralíticos) del entorno de la cuenca. La fosilización y posterior subsidencia de los suelos hidromorfos dio origen a la conversión de los horizontes superfi ciales en las capas de carbón y a la compactación de los materiales. Posteriormente, el material torrencial de cobertura fue edafi zado de nuevo con mayor o menor intensidad y duración. En los sistemas laterales de los depósitos aluvio-torrenciales se han identifi cado Plinthosoles, suelos rojos fermonosialíticos muy evolucionados y corazas lateríticas, lo que pone, [EN] The excavation of the lignite mine of As Pontes, almost to its base, allowed to sample and study in detail the nature and process of formation of an Oligocene-Miocene lignite deposit with up to 500 m of sedimentary material, produced in a time span of 10-11 million years. The site is characterized by alternating layers of coal (lignite) and detrital sediments of varied texture. Within the sequence the process of coal formation seems to have occurred mostly in a swampy environment, with vegetation dominated by Juncus and Thypha, that developed on hydromorphic soils, mainly Gleysols and Histosols. At a pH close to neutrality and under anoxic-suboxic conditions, Fe was reduced to ferrous state, leading to the formation of nodules and concretions of siderite and biogenic sulfi des. Siderite, is clearly associated to the rhizosphere of aquatic plants in gleyic soil horizons, with segregation and mobilization of Fe, being root respiration clearly related to the formation of the mineral. These soils had surface horizons rich in organic matter (H o A) which were later fossilized by fl uvial-torrential sediments derived from soils and saprolites of kaolinitic soils formed in well-drained conditions (probably lateritic soils) at the margins of the basin. Fossilization and subsequent subsidence of the hydromorphic soils led to the transformation of surface horizons into lignite and the compaction of the materials. Afterthat, the new sediments underwent pedogenesis with varying intensity and duration. In the systems at the margins of basin Plinthosols, fermonosialithic red soils highly evolved and lateritic crusts were found, which highlights the variety of soil conditions and climate evolution that occurred. Alternating conditions of biostaxy (formation of hydromorphic soils in the watershed and well drained, kaolinitic soils in the slopes) and rhesistaxy (erosion, alluvium-torrential sedimentation and fossilization of soils) may be responded to climatic change (probably

Effects of the landspreading of pig slurry on the yield and composition of capsi cum annuum. M. P. Bernal, A. Roig, J. Cegarra and R. Madrid.-- Características micromorfológicas de suelos de humedales en zonas semiáridas (Cuenca del Duero). J. Benayas, M. a T. de la Cruz y J. M. a Rey. Benayas.-- Aplicación de la técnica de porosimetría por intrusión de mercurio en el estudio de la porosidad de un conjunto de suelos del NW de España. E. Benito, A. Paz y R. Pini.-- Cambios físicos y químicos durante la maduración de Vitis vinífera, variedad Monastrell, en la D. O. Jumilla. G. Navarro, F. Pardo, P. Jiménez, J. Oliva y S. Navarro.-- Micorrizas vesículo - arbusculares en parcelas que se encuentran en sucesión- regeneración en Jos Andes tropicales. M. Montilla, R. A. Herrera y M. Monasterio.-- Efectos de los incendios forestales sobre el suelo. J. González, M. C. Fernández y G.P. Gimeno.-- Mineralogía de suelos formados sobre calizas en Galicia. M. T. Taboada, M. B. Silva y M. c. Villar.-- Efecto de tratamientos foliares con Ti (IV) sobre nutrición, producción y calidad de fruto en plantas de Capsicum annuum, L. F. Martínez-Sánchez, J. L. Giménez, M. Carvajal, A. Moreno, J. L. Fuentes y C. F. Alcaraz.-- Poder discriminante de las clasificaciones: aplicación a los suelos de la depresión Guadix- Baza (Granada). A. Iriarte, E. Barahona y C. Gil de Carrasco.-- Aspects of elm propagation by soft and hardwood cuttings. L. Mittempergher, G. Bartolini, F. Ferrini and M. Panicucci.-- Metales pesados en las escombreras de la mina Puentes (La Coruña): influencia de las condiciones Eh- pH. F. Macíass, M. T. Barral, C. Monterroso y R. M. Calvo.-- Incidencia del fósforo en la mineralización del nitrógeno orgánico de un lodo de depuradora en dos suelos calizos. Extracción mediante EUF. l. Verdú, l. Gómez, F. Burló y J, Mataix.-- Dinámica del proceso de sorción de fósforo en suelos. Definición de indicadores. T. Crisanto y P. P. Iturbe.-- Estudio de la adsorción de atrazina por polimero

A comparative study of the effect of soil boron on yield, yield attributes and nutrient uptake by susceptible and tolerant varieties of wheat. Por B. R. Chhipa and P. Lal.-- Suelos y vegetación de las Peñas de Aya (Navarra y Guipúzcoa. Por J. Peralta, J. Íñiguez y J. C. Bascones.-- Presencia de horizonte plácico en Ñadis (Placaquands) y Trumaos (Placudands) en el sur de Chile. Por W. Luzio, C. Barros, M. Aroncibia y S. Alcayaga.-- Retención de 0,0-Dimetil, S-(Z, Metilamino- 2, Oxoetil -Ditiofosfato (Dimetoato) por Vermiculitas homoionicas. l.-cinética del proceso. Por C. Valenzuela Calahorro, A. García Rodríguez y A. Bernalte García.-- Estudio edafogenético en suelo~ de Rañas. Distribución de hierro y aluminio. Por Mª P. García Rodr(guez, J. Forteza Bonnin, y L. F. Lorenzo Martín.-- Water retention equations and their relationship with particle size distribution and bulk density for undisturbed samples. Por A. Andriulo, N. Amiotti y C. Pecorari.-- Evolución regresiva de diversos parámetros edáficos en agroecosistemas (Cafetales, cañaverales) derivados del bosque mesófilo de montaña (México). Por N. García Calderón, F. Velasco y N. Aguilera.-- Micronutrients distribution in grown soils (Fe and Zn) prediction equations of contenta. Por A. Ruiz-Nieto, E. Barahona, S. Jaime, F. Huertas, A. Aguilar and J. Linares.-- Contenido de azufre total en muestras superficiales de suelos de la provincia de la Coruña. Por A. Merino García, C. Monterroso Martínez y E. García -Rodeja G.-- Aspectos termodinámicos de la adsorción de Clorprofan por suelos. Por G. Dios Cancela, J. A. Guillén Alfara y S. González García.-- Consideraciones acerca de las interralaciones entre suelos. Vegetación y paleoprocesos morfogenéticos en el Macizo de Ayllón y la Sierra de Alto Rey (Sector oriental del Sistema Central). Por J. J. Ibáñez Martín, F. Fernández González y A. García Alvarez.--Composición Geoquímica de unas ferricretas en el entorno de un monte isla de Ciudad Real. Por R. Jiménez Ballesta, A

El lenguaje es una capacidad humana compleja y necesaria para relacionarnos con los demás; por ello, cualquier problema o interrupción que se produzca en él genera un quiebre en la comunicación, lo cual repercutirá en el desarrollo del niño. El presente estudio de caso tiene como objetivo diseñar un plan de evaluación e intervención que responda a las dificultades que muestra un niño de 5 años 3 meses con trastorno del lenguaje, el cual es definido como la anormal adquisición, comprensión o expresión del lenguaje hablado o escrito, que puede estar relacionado a uno o a todos los componentes del sistema lingüístico. En el plan de intervención se priorizan los componentes léxico semántico en los contenidos de vocabulario y relaciones de significado entre palabras y, morfosintáctico con el contenido de organización y estructuración gramatical. Los resultados obtenidos evidencian un incremento sustancial de vocabulario que permitió al niño comunicarse con mayor precisión y relacionar conceptos de manera acertada, logrando realizar asociaciones por similitud, categoría semántica y complementariedad; además de, producir oraciones simples con una adecuada concordancia gramatical. Se concluye que el proceso de intervención favoreció el desarrollo del componente léxico semántico a nivel comprensivo y expresivo así como del componente morfosintáctico, según los contenidos programados.