Availability and transfer to grain of As, Cd, Cu, Ni, Pb and Zn in a barley agri-system: Impact of biochar, organic and mineral fertilizers

With biochar becoming an emerging soil amendment and a tool to mitigate climate change, there are only a few studies documenting its effects on trace element cycling in agriculture. Zn and Cu are deficient in many human diets, whilst exposures to As, Pb and Cd need to be decreased. Biochar has been shown to affect many of them mainly at a bench or greenhouse scale, but field research is not available. In our experiment we studied the impact of biochar, as well as its interactions with organic (compost and sewage sludge) and mineral fertilisers (NPK and nitrosulfate), on trace element mobility in a Mediterranean agricultural field (east of Madrid, Spain) cropped with barley. At harvesting time, we analysed the soluble fraction, the available fraction (assessed with the diffusive gradients in thin gels technique, DGT) and the concentration of trace elements in barley grain. No treatment was able to significantly increase Zn, Cu or Ni concentration in barley grain, limiting the application for cereal fortification. Biochar helped to reduce Cd and Pb in grain, whereas As concentration slightly increased. Overall biochar amendments demonstrated a potential to decrease Cd uptake in cereals, a substantial pathway of exposure in the Spanish population, whereas mineral fertilisation and sewage sludge increased grain Cd and Pb. In the soil, biochar helped to stabilise Pb and Cd, while marginally increasing As release/mobilisation. Some of the fertilisation practises or treatments increased toxic metals and As solubility in soil, but never to an extent high enough to be considered an environmental risk. Future research may try to fortify Zn, Cu and Ni using other combinations of organic amendments and different parent biomass to produce enriched biochars.

Experiencias de Educación Vial en Asturias : premiadas por la D.G.T. en el Concurso Nacional de 2007.

'Un viaje a la fantasía' del CP de Lada y el proyecto 'Puntos grises' del IES de Candás merecieron dos primeros premios, al tiempo que 'Trompita y la Educación Vial' del CP Begoña de Gijón y la experiencia 'Una calle para todos' del CP El Parque de Blimea, se hicieron acreedores a dos de los segundos premios otorgados

Educación vial.

Se desarrolla un proyecto de innovación educativa que pretende que toda la comunidad educativa del CRIELE trabaje en torno a la Educación Vial y la seguridad en todos los aspectos con el alumnado de Educación Primaria. El trabajo se ha desarrollado en tres fases: en la primera se preparan las actividades y materiales; en la segunda se desarrollan las actividades a lo largo de todo el curso, siendo la planificación semanal en función de la asistencia de los grupos; y en el tercer momento se realiza la evaluación de las actividades desarrolladas a lo largo de todo el curso semanalmente al finalizar la estancia de cada uno de los grupos. Para la realización del proyecto se utiliza fundamentalmente el parque de tráfico homologado por la DGT y ubicado en el CRIELE con los kars, diverso material gráfico y de cartelería, juegos didácticos, chalecos homologados, muñecos de primeros auxilios y materiales diversos para la creación de un semáforo. Se ha creado una amplia variedad de materiales como elementos decorativos, murales señales viales, semáforos, adornos, viseras y chalecos viales, fichas viales, planos, revistas, cuadernillos o carnets. En el CRIELE acuden grupos escolares de diferentes localidades semanalmente y disfrutan de una convivencia continuada y una planificación de actividades desde el plano socioeducativo. Se trabaja intensamente el tema transversal y línea prioritaria a tratar en el currículo, Educación Vial y seguridad, en todos sus aspectos, desde diferentes ángulos y visiones, tratando de alcanzar la educación integral de base en el alumnado como peatón y futuro conductor responsable del hoy y del mañana. Un logro importante alcanzado es el grado de coordinación de los centros de origen con el tema antes de la convivencia de los alumnos y alumnas, y después, ya que al finalizar se entrega a cada persona toda la documentación generada para seguir trabajando desde sus lugares de procedencia con los tutores.

Construcción de un programa de modificación de actitudes hacia el tráfico y de comportamiento en el uso del ciclomotor para su aplicación al finalizar la educación secundaria.

Evaluar el comportamiento en el uso del ciclomotor y/o bicicleta y las actitudes de los jóvenes en educación secundaria. Construir un programa de modificación de actitudes y comportamientos en el uso del ciclomotor y/o bicicleta para la misma etapa. Evaluar la eficacia en la aplicación del programa.. Está constituida por 140 adolescentes de edades comprendidas entre los 16 y los 18 años; pertenecen a centros de educación secundaria que voluntariamente desearon participar en un 'programa de sensibilización hacia los problemas del tráfico con ciclomotor'.. Parte de la justificación teórica sobre la necesidad de modificar las actitudes para reducir la accidentabilidad. Hace referencia a los informes anuales de la Dirección General de Tráfico pública (DGT) . Se elabora un programa de intervención cuyos fines son los siguientes: 1. dar información a los jóvenes acerca de las causas y consecuencias de los accidentes de tráfico; 2. intentar eliminar falsas creencias acerca del control en el manejo del ciclomotor y-o bicicleta; 3. desarrollar recursos de actuación para hacer frente a situaciones de riesgo. La variable independiente en este estudio es el programa de enseñanza. Las variables de control son: la personalidad, estilos de vida y habilidades sociales. Las variables dependientes son: las actitudes hacia la seguridad vial, los conocimientos de normativa sobre tráfico y la tendencia a elegir conductas de conducción seguras.. Se aplican diferentes pruebas: a. un cuestionario de personalidad de Eysenck y Eysenck; b. un cuestionario sobre estilos de vida; c. un cuestionario de habilidades sociales; d. un cuestionario de actitudes ante la seguridad vial; e. un test estándar para evaluar los conocimientos sobre la normativa de tráfico; f. un cuestionario situacional para evaluar la intensidad en la tendencia a elegir conductas de conducción seguras.. Se trata de un estudio cuasi experimental con grupos no equivalentes: grupo en espera, grupo de control y grupo experimental. A este último se le administra el programa de modificación de actitudes hacia el tráfico y de comportamientos en el uso del ciclomotor y/o bicicleta (PMCAT); el grupo de control recibió un programa de sensibilización general hacia las normas de tráfico; el grupo de espera no recibió ningún programa. Los resultados se reflejan en tablas y gráficos en los que aparecen numerosos estadísticos descriptivos.. El PMCAT ha servido para mejorar en el grupo de adolescentes sus habilidades sociales para defender una actitud de seguridad y rechazar conductas arriesgadas. Han mejorado también significativamente los comportamientos de seguridad así como sus creencias respecto a las actitudes que sus compañeros tienen a partir de ahora en relación al uso del ciclomotor.. Se confirman las expectativas del estudio en cuanto se da una mejora significativa en las actitudes y las conductas contra el riesgo. Sin embargo se ve la necesidad de continuar realizando estudios de este tipo con la finalidad de aumentar la tolerancia y el respeto hacia las normas..

Trace-metal biogeochemistry in the Mediterranean Thau Lagoon, a shellfish farming area

The present study contributes to the knowledge of the biogeochemistry of Pb, Cd, Cu, and Ni in the Mediterranean Than Lagoon, southern France, which is an important shellfish farming system. The concentrations of the metals were determined in sediment cores and the overlying waters using inductively coupled plasma mass spectrometry. Particular attention was given to the determination of dissolved Cu species because of their dual role as essential nutrient and toxicant to planktonic organisms. Dissolved Cu speciation was determined using the diffusive gradient in thin-film technique (DGT) and competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV). Our data indicated a significant historical contamination of the sediments, which commenced in the second half of the 19th century, with trace metal inputs persisting until the end of the 20th century. In recent years a decrease in metal contamination has become apparent. The maxima observed for Pb, Cd, and Cu profiles probably indicate the occurence of anoxia crises. A strong complexation of the dissolved Cu species was observed in the waters of the Than Lagoon, which reduced the bioavailability of Cu. The dissolved Cu(2+) concentrations were probably too low to cause direct toxic effects on shellfish, but the highest concentration (5.29 pM) observed in this study can potentially influence phytoplankton communities. A comparison between the Cu speciation data indicates that up to 50% of the complexed Cu determined using CLE-ACSV was DGT labile.

Trace metal speciation in the Pieman River catchment, western Tasmania

The Pieman River catchment has seen continuous mining of economic deposits of gold, silver, lead, copper, zinc and tin since the 1870’s. Tributaries of this river which receive mining effluent, either directly or from acid mine drainage (AMID), have total metal concentrations considerably above background levels and are of regulatory concern. The lower Pieman River is however classified as a State Reserve in which recreational fishing and tourism are the major activities. It is therefore important that water entering the lower Pieman River from upstream hydroelectric impoundments is of high quality. Metals in natural waters exist in a variety of dissolved, colloidal and particulate forms. The bioavailability and hence toxicity of heavy metal pollutants is very dependant on their physico form. Knowledge of the speciation of a metal in natural aquatic environments is therefore necessary for understanding its geochemical behaviour and biological availability. Complexation of metal ions by natural ligands in aquatic systems is believed to play a significant role in controlling their chemical speciation. This study has investigated temporal and spatial variation in complexation of metal ions in the Pieman River. The influence of pH, temperature, organic matter, salinity, ionic strength and time has been investigated in a series of field studies and in laboratory-based experiments which simulated natural and anthropogenic disturbances. Labile metals were measured using two techniques in various freshwater and estuarine environments. Diffusive gradients in thin-films (DGT) allowed in situ measurement of solution speciation whilst differential pulse anodic stripping voltammetry (DPASV) was used to measure labile metal species in water samples collected from the catchment. Organic complexation was found to be a significant regulating mechanism for copper speciation and the copper-binding ligand concentration usually exceeded the total copper concentration in the river water. Complexation was highly dependent on pH and at the river-seawater interface was also regulated by salinity, probably as a result of competitive complexation by major ions in seawater (eg. Ca 2+ ions). Zinc complexation was also evident, however total zinc concentrations in the water column often far exceeded the potential binding capacity of available ligands. In addition to organic complexation, Zn speciation may also be associated with adsorption by flocculated or resuspended colloidal Mn and/or Fe oxyhydroxides. Metal ion complexation and hence speciation was found to be highly variable within the Pieman River catchment. This presents major difficulties for environmental managers, as it is therefore not possible to make catchment-wide assumptions about the bioavailability of these metals. These results emphasise the importance of site-specific sampling protocols and speciation testing, ideally incorporating continuous, in situ monitoring.

Caracterização funcional de dois cDNAs homólogos à ciclofilina e à proteína reprimida por auxina (ARP) identificados em bibliotecas subtrativas a para floração em tomateiro

Flowering is a fundamental process in the life cycle for plant. This process is marked by vegetative to reproductive apical meristem conversion, due to interactions between several factors, both internal and external to plant. Therefore, eight subtractive libraries were constructed using apical meristem induced or not induced for two contrasting species: Solanum lycopersicum cv. Micro-Tom and Solanum pimpinellifolium. Several cDNAs were identified and among these, were selected two cDNAs: one homologous cDNA to cyclophilin (LeCYP1) and the other to Auxin repressed protein (ARP). It has observed that LeCYP1 and ARP genes are important in the developmental process to plants. In silico analysis, were used several databases with the exclusion criterion E-value <1.0x10-15. As a result, conservation was observed for proteins analyzed by means of multiple alignments and the presence of functional domains. Then, overexpression cassettes were constructed for the ARP cDNA in sense and antisense orientations. For this step, it was used the CaMV35S promoter. The cDNA orientation (sense or antisense) in relation to the promoter was determined by restriction enzymes and sequencing. Then, this cassette was transferred to binary vector pZP211 and these cassettes were transferred into Agrobacterium tumefaciens LBA4404. S. lycopersicum cv. Micro-Tom (MT) and MT-Rg1 plants were transformed. In addition, seedlings were subjected to hormone treatments using a synthetic auxin (- naphthalene acetic acid) and cyclosporin A (cyclophilin inhibitor) treatments and it was found that the hormone treatment there were changes in development of lateral roots pattern, probably related to decreases in auxin signaling caused by reduction of LeCYP1 in MT-dgt plants while cyclosporin A treatments, there was a slight delay in flowering in cv. MT plants. Furthermore, assay with real-time PCR (RT-qPCR) were done for expression level analysis from LeCYP1 and ARP in order to functionally characterize these sequences in tomato plants.

Coeficientes de difusão de metais em materiais não convencionais (agarose e acetato de celulose) usados na técnica de difusão em filmes finos por gradientes de concentração

The DGT technique allows one to measure quantitatively free and labile metal species in aquatic systems. Nevertheless, for this approach, knowledge is required of the diffusion coefficients of the analytes in a diffusive layer. In this study, the diffusion coefficients of Hg(II), As(III), Mn(II), Mg(II), Cu(II), Cd(II) were determined in agarose gel and those of Ba(II), Cd(II), Cu(II), Mg(II), Mn(II) e Zn(II) in cellulose acetate membranes. These materials presented good performance and the reported results can be used as a data base for further DGT studies.

Biochemical and histological characterization of tomato mutants

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biochemical dissection of diageotropica and Never ripe tomato mutants to Cd-stressful conditions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Tomato (Solanum Lycopersicum cv. Micro-Tom) Natural Genetic Variation Rg1 and the DELLA Mutant Procera Control the Competence Necessary to Form Adventitious Roots and Shoots

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Use of diffusive gradients in thin films and tangential flow ultrafiltration for fractionation of Al(III) and Cu(II) in organic-rich river waters

Diffusive gradients in thin films (DGT) and tangential-flow ultrafiltration (TF-UF) were combined for fractionation of Al and Cu in river water containing high content of dissolved organic carbon. A procedure based on ultrafiltration data is proposed to determine diffusion coefficients of the analytes in water samples and model solutions containing both free metal (M) and complex (metal - humic substance). Aiming to evaluate the accuracy of the proposed approach, the DGT results were compared with those from a protocol for determination of labile Al and Cu based on solid phase extraction (SPE). Good agreement between data from DGT and SPE were attained for model solutions. For analysis of real organic-rich water samples, differences between DGT and SPE measurements were consistent with the time-scales of the techniques. The concentration of labile Al determined by DGT were lower than the total dissolved concentrations (determined by inductively coupled plasma mass spectrometry) and exceeded the ultrafiltered concentration, indicating that inorganic Al species (species small enough to pass through 1 kDa membrane) were minor species as compared with Al organic complexes. For both Al and Cu, there were species not measured by DGT as they are not sufficiently labile. (C) 2007 Elsevier B.V. All rights reserved.

Speciation of lead in seawater and river water by using Saccharomyces cerevisiae immobilized in agarose gel as a binding agent in the diffusive gradients in thin films technique

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Paper-based diffusive gradients in thin films technique coupled to energy dispersive X-ray fluorescence spectrometry for the determination of labile Mn, Co, Ni, Cu, Zn and Pb in river water

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determination of labile inorganic and organic species of Al and Cu in river waters using the diffusive gradients in thin films technique

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)