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Acción colectiva e imaginarios en disputa. Etnografía a los asentamientos pro sustentabilidad en Chile
(Universidad de Chile, 2019)
Balance Social.
(Universidad de ChileUniversidad de Chile. Programa Cybertesis, 2004)
internacionales sobre sustancias peligrosas. 33
Convenio de Basilea 34
Protocolo De Montreal 36
- 3 -
Convenio De Rotterdam 37
Convención Sobre Contaminantes Orgánicos Persistentes 39
La influencia de los Acuerdos Internacionales en las Políticas...
producción de residuos. Según estudios publicados por la ONU la población mundial a finales del año 2003 es de 6,3 billones y se proyecta que la población mundial en el año 2050 será de 8,9 billones. Se esta creciendo a la tasa del 1,2% anual lo que...
producción de residuos. Según estudios publicados por la ONU la población mundial a finales del año 2003 es de 6,3 billones y se proyecta que la población mundial en el año 2050 será de 8,9 billones. Se esta creciendo a la tasa del 1,2% anual lo que...
Influencia de la aplicación de biosólidos sobre la biodisponibilidad de elementos traza (Cu, Cr, Ni Y Zn) en suelos, determinada a travéz de un método predictivo (DGT) y bioensayos con plantas de maravilla (Helianthus annuus)
(Universidad de Chile, 2014)
razón, los biosólidos pueden ser benéficamente utilizados como co-fertilizantes en suelos agrícolas o en la recuperación de suelos degradados. No obstante, los biosólidos poseen metales pesados y otros contaminantes orgánicos que pueden contribuir a la...
One of the use options that currently is being given to the stabilized sludge or biosolids, is their application in agricultural soils due to the high content of organic matter, macro and micro nutrients required for plant growth, therefore, biosolids can be beneficially co-used as fertilizer on agricultural land or in the recovery of degraded soils. However, biosolids have heavy metals and other organic pollutants that can contribute to the soils contamination, and through of this medium, to reach to groundwater and agricultural land. To assess on the soil, the environmental effect of a contaminant, it is necessary knowing its bioavailable fraction. The bioavailable fraction determination is important in evaluating the risk of contamination, and can be estimated by various methods, one of them is the sequential extraction procedure, which involves the use of different reagents, to obtain the metal form, which is associated with different components of the soil. Bioavailability is usually determined through living systems, which help to study the level and/or impact of the pollutants on the environment, which requires more work and time. For this reason, new techniques have been developed, to simulate this parameter faster and equally reliable: the technique of diffusion gradient in thin film (DGT) employs a cation exchange resin Chelex, a diffusive gel and filter membrane in a plastic device, so that the ions diffuse through the filter and to achieve diffusive resin gel and thus, mimic metal uptake by the plant. To relate the metal concentration in the resin with bioavailability, a computational model DIFS (DGT Induced Fluxes in Soils and Sediments) that quantifies the response of DGT in relation to the diffusion characteristics of the soil and the rate of supply from the solution to solid phase. This study assessed the influence of biosolid application to soil at various rates,: 0, 30, 90 and 200 Mg ha-1, on bioavailability of some trace elements (Cu, Cr, Ni and Zn) in agricultural soils of the Metropolitan Region. Three methods were used to determine the metal bioavailability in soils: bioassay with sunflower plants (Helianthus annuus), the first fraction of a sequential extraction procedure (BCR) and diffusion gradient in thin films technique (DGT). Excepting Ni, metal concentrations, in the biosolids are under of the limits allowed by the Chilean regulation (DS-4, 2009), to be applied to agricultural soils as a method of disposal. The metal concentration in the biosolid and soils increases in the following order: Ni < Cu < Cr < Zn , and Ni < Cr < Cu < Zn respectively. The results in the sequential extraction procedure showed that the metals are mainly found in the residual fraction of the soil, the application of biosolids generally decreased this fraction, while there was an increase in the acid soluble fraction or labile fraction, usually associated with the bioavailability. The contents of trace elements in plants grown in the soils studied, increased with increasing biosolids rates, applied to soils.CE for Cu, determined with DGT technique, decreased with increasing biosolid rate, however, CE for Cr, Ni and Zn increased by the biosolids rate applied at different soils. The results obtained for metal contents in sunflower plants, the concentration in the acid soluble fraction through sequential extraction procedure, and the CE determined by DGT-DIFS technique, were compared using an analysis of simple regression, to assess the efficiency of these techniques respect of the metal bioavailability estimation in soils. The metal content in plants and CE showed a good correlation only for Zn in Lampa soil (R = 0,862), the correlation coefficient for Cr and Zn in the Lampa soil, was achieved by comparing the metals content in the plants and the acid soluble fraction, was 0,879 and 0,941 respectively, while in other soils, were obtained correlation coefficients no significant. However, the comparison with the acid-soluble fraction and CE shown the best correlation coefficients for Cr, Ni and Zn in the three soils studied...
One of the use options that currently is being given to the stabilized sludge or biosolids, is their application in agricultural soils due to the high content of organic matter, macro and micro nutrients required for plant growth, therefore, biosolids can be beneficially co-used as fertilizer on agricultural land or in the recovery of degraded soils. However, biosolids have heavy metals and other organic pollutants that can contribute to the soils contamination, and through of this medium, to reach to groundwater and agricultural land. To assess on the soil, the environmental effect of a contaminant, it is necessary knowing its bioavailable fraction. The bioavailable fraction determination is important in evaluating the risk of contamination, and can be estimated by various methods, one of them is the sequential extraction procedure, which involves the use of different reagents, to obtain the metal form, which is associated with different components of the soil. Bioavailability is usually determined through living systems, which help to study the level and/or impact of the pollutants on the environment, which requires more work and time. For this reason, new techniques have been developed, to simulate this parameter faster and equally reliable: the technique of diffusion gradient in thin film (DGT) employs a cation exchange resin Chelex, a diffusive gel and filter membrane in a plastic device, so that the ions diffuse through the filter and to achieve diffusive resin gel and thus, mimic metal uptake by the plant. To relate the metal concentration in the resin with bioavailability, a computational model DIFS (DGT Induced Fluxes in Soils and Sediments) that quantifies the response of DGT in relation to the diffusion characteristics of the soil and the rate of supply from the solution to solid phase. This study assessed the influence of biosolid application to soil at various rates,: 0, 30, 90 and 200 Mg ha-1, on bioavailability of some trace elements (Cu, Cr, Ni and Zn) in agricultural soils of the Metropolitan Region. Three methods were used to determine the metal bioavailability in soils: bioassay with sunflower plants (Helianthus annuus), the first fraction of a sequential extraction procedure (BCR) and diffusion gradient in thin films technique (DGT). Excepting Ni, metal concentrations, in the biosolids are under of the limits allowed by the Chilean regulation (DS-4, 2009), to be applied to agricultural soils as a method of disposal. The metal concentration in the biosolid and soils increases in the following order: Ni < Cu < Cr < Zn , and Ni < Cr < Cu < Zn respectively. The results in the sequential extraction procedure showed that the metals are mainly found in the residual fraction of the soil, the application of biosolids generally decreased this fraction, while there was an increase in the acid soluble fraction or labile fraction, usually associated with the bioavailability. The contents of trace elements in plants grown in the soils studied, increased with increasing biosolids rates, applied to soils.CE for Cu, determined with DGT technique, decreased with increasing biosolid rate, however, CE for Cr, Ni and Zn increased by the biosolids rate applied at different soils. The results obtained for metal contents in sunflower plants, the concentration in the acid soluble fraction through sequential extraction procedure, and the CE determined by DGT-DIFS technique, were compared using an analysis of simple regression, to assess the efficiency of these techniques respect of the metal bioavailability estimation in soils. The metal content in plants and CE showed a good correlation only for Zn in Lampa soil (R = 0,862), the correlation coefficient for Cr and Zn in the Lampa soil, was achieved by comparing the metals content in the plants and the acid soluble fraction, was 0,879 and 0,941 respectively, while in other soils, were obtained correlation coefficients no significant. However, the comparison with the acid-soluble fraction and CE shown the best correlation coefficients for Cr, Ni and Zn in the three soils studied...
Informe País: Estado del medio ambiente en Chile. Comparación 1999-2015
(Universidad de Chile, Instituto de Asuntos Públicos, 2016)
.3.2.1. Control de residuos industriales y silvoagropecuarios 145
2.3.3. Marco jurídico institucional 146
2.3.3.1. Caudales ecológicos 146
2.3.3.2. Instrumentos de gestión de la le ley 19.300 148
2.3.3.3. Organizaciones de usuarios de agua 150
2...
expansión urbana 513 8.2.4 Áreas verdes 514 8.2.5 Reciclaje 516 8.2.6 Generación de residuos 518 8.2.6.1 Residuos Sólidos Municipales (RSM) 518 8.2.6.2 Residuos Sólidos Industriales (RSI) 520 8.2.6.3 Residuos Industriales Líquidos (RILES) 521 8...
expansión urbana 513 8.2.4 Áreas verdes 514 8.2.5 Reciclaje 516 8.2.6 Generación de residuos 518 8.2.6.1 Residuos Sólidos Municipales (RSM) 518 8.2.6.2 Residuos Sólidos Industriales (RSI) 520 8.2.6.3 Residuos Industriales Líquidos (RILES) 521 8...
Evaluación experimental de las saponinas del quillay (Quillaja saponaria) como inhibidora del desarrollo de coccidias intestinales en pollos de engorda
(Universidad de Chile, 2014)
,
constituyendo un problema de Salud Pública. Todo esto, sumado a las políticas de
inocuidad alimentaria que restringen la presencia de residuos de medicamentos en los
alimentos, ha conllevado al desarrollo de vacunas y/o programas de rotación de vacunas
4...
silvestres y polvo. La viabilidad del ooquiste es de pocos días en la cama de aves y de hasta semanas en el suelo, viéndose disminuida por la liberación de calor y amonio por compostaje y la acción de bacterias. El ooquiste muere al ser expuesto a...
silvestres y polvo. La viabilidad del ooquiste es de pocos días en la cama de aves y de hasta semanas en el suelo, viéndose disminuida por la liberación de calor y amonio por compostaje y la acción de bacterias. El ooquiste muere al ser expuesto a...
Parque de la tierra. Los Maitenes - Puchuncaví
(Universidad de Chile, 2015)
Bioseguridad en ganadería ovina de la zona centro-sur perteneciente a la agricultura familiar campesina
(Universidad de Chile, 2008)
, ropas,
botas, etc., desinfectándolos correctamente.
iii. Luego de transcurrido el periodo de cuarentena de un grupo de animales, el corral debe
ser limpiado correctamente, eliminando los desechos orgánicos y restos de alimento y luego
desinfectado de...
Centro de capacitación e investigación en montaña : El Manzano, Cajón del Maipo
(Universidad de Chile, 2012)
Utilización agroindustrial del nopal
(FAO, 2006)
114
Uso como leña 115
Utilización de residuos de nopal en la producción de biogás 115
Usos de residuos para lombricultura y...
Centro de Encuentro y Educación del Vino : comuna de Nancagua
(Universidad de Chile, 2018)