Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-Graduação em Química. / Made available in DSpace on 2012-10-19T01:29:15Z (GMT). No. of bitstreams: 0 / Este trabalho consiste do estudo das características ácidas de substâncias Húmicas (SH) sedimentares extraídas dos manguezais dos Rios Itacorubi e Ratones (Ilha de Santa Catarina), através de métodos químicos e de titulação potenciométrica. Os dados potenciométricos foram tratados por regressão linear da curva de titulação, usando o método modificado de Gran, assim como por regressão não´linear, usando o programa BEST7. As interações metal-SH foram estudadas com os seguintes íons metálicos: Cu+2, Zn+2 e Fe+3.

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Copies of author's previously published works inserted. Bibliography: leaves 260-299. This thesis describes the concept of organic matter turnover and various methods to measure the decay rates of organic materials in the soil. Methods are developed to separate SOM from different locations within the soil matrix. Free particulate organic matter (POM), located between or outside the soil aggregates is isolated. Occluded POM is disaggregeted by sonification. The compositional differences noted among the three components of SOM are used to describe the changes that OM undergoes during decomposition. The process is followed as organic matter enters the soil, is enveloped in aggregates and is eventually incorporated into the microbial biomass and metabolites then becoming associated with clay minerals.

Copies of author's previously published works inserted. / Bibliography: leaves 260-299. / xxii, 299 leaves, [7] leaves of plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis describes the concept of organic matter turnover and various methods to measure the decay rates of organic materials in the soil. Methods are developed to separate SOM from different locations within the soil matrix. Free particulate organic matter (POM), located between or outside the soil aggregates is isolated. Occluded POM is disaggregeted by sonification. The compositional differences noted among the three components of SOM are used to describe the changes that OM undergoes during decomposition. The process is followed as organic matter enters the soil, is enveloped in aggregates and is eventually incorporated into the microbial biomass and metabolites then becoming associated with clay minerals. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1997

Memoria para optar al título de Químico / La materia orgánica disuelta (MOD) presente en suelos, aguas superficiales, y enmiendas orgánicas (EO) puede modificar los procesos de adsorción de contaminantes como metales pesados, pesticidas y Bifenilos Policlorados (PCBs), por la formación de complejos solubles en agua que pueden movilizarse a través del perfil de suelo. Dentro de los contaminantes orgánicos de mayor interés están los PCBs por su alta toxicidad, persistencia y bioacumulación, que constituyen una familia de 209 congéneres, los cuales pueden difundir a través del medioambiente. El objetivo de este estudio fue evaluar la movilidad de PCBs a través del perfil de suelo por efecto de la MOD de distintas fuentes; así como la movilidad de estos contaminantes por efecto de la incorporación de EO a un suelo contaminado. Para las experiencias se utilizó suelo de la Región Metropolitana del sector de La Farfana (LF), Santiago, Chile (UTM 19H 0331733, 6293931), el cual fue fortificado con una mezcla de 8 congéneres de PCB (8, 20, 28, 52, 101, 118, 138 y 180), por otro lado se prepararon mezclas de suelos con adición de PCB y EO (Humex) a distintos niveles de carbono orgánico (CO) ( 0 – 5,6 - 12 y 25 % CO). Se desarrolló una metodología de extracción con solvente y sonicación para estimar la concentración pseudototal de PCB en los suelos fortificados. Para evaluar la movilidad de PCB en columnas de suelo se utilizó MOD proveniente de Suelo LF, Biosólido, Humex y Ac. Húmico comercial. Para los experimentos de movilidad se utilizaron columnas de vidrio para empacar los suelos, las cuales fueron conectadas a los cartridge de C-18 para realizar la extracción en fase sólida (SPE) de forma continua, los eluidos recolectados fueron llevados a sequedad y reconstituidos con nhexano con adición de estándar interno para su cuantificación mediante GC-μECD. A partir de los resultados de la caracterización de los suelos se determinó que posee una textura Franco Arenosa, con un alto contenido de Cu y Mn, pH en agua de 8,09 y una capacidad de intercambio catiónico de 34 cmolkg-1. Los resultados de la optimización de la metodología desarrollada para la determinación del contenido seudototal de los PCB en suelo, dieron cuenta que el tiempo de sonicación es un factor que interviene en los porcentajes de extracción de los analitos, donde se determinó que existe una relación indirecta entre el PCB analizado y el porcentaje de recuperación obtenido, determinándose que para los PCB 28 y 180 el tiempo al cual se obtuvo un mayor porcentaje de recuperación fue de 15 min, para el PCB 52 de 60 min y para el PCB 101 de 20 min. Los porcentajes no siguieron una tendencia clara, lo que puede estar relacionado al efecto matriz observado en el suelo sin fortificar. Con respecto a la caracterización de la materia orgánica disuelta utilizada para este estudio se determinó a través de los espectros de IR-TF, así como la determinación de SUVA que la distribución de los grupos funcionales presentes en la MOD, así como su polaridad, depende del origen de ésta, determinándose una similitud entre los espectros de IR-TF LF -Acido húmico comercial, y MOD de Humex –Biosólido. A partir de los experimentos de movilidad de PCB a través del perfil de suelos se determinó que no hay diferencias significativas en cuanto al origen de la MOD, por lo que la movilidad podría estar influenciada, principalmente por la MOD de Suelo LF Finalmente los resultados de la lixiviación de los congéneres de PCB a través del suelo con adición de EO fueron directamente proporcional a la cantidad de enmienda incorporada al suelo, siendo aquellos con menor grado de cloración más eluidos. A través de la determinación del contenido de CO fue posible establecer que los PCBs son movilizados por la MOD proveniente del suelo, y que las EO aportan MOD que incrementa la movilidad de estos contaminantes orgánicos a través del perfil de suelo / Dissolved organic matter (DOM) present in soil, water, and organic amendments (OA) can modify the adsorption of pollutants such as heavy metals, pesticides and polychlorinated biphenyls (PCBs), by forming water-soluble complexes that can move through the soil profile. Among the organic pollutants of greatest interest are PCBs, due to their high toxicity, persistence and bioaccumulation, which constitute a family of 209 congeners, which can spread through the environment. The aim of this study was to assess the mobility of PCBs through the soil profile by the effect of MOD from different sources; as well as mobility of these contaminants due to the addition of OA to contaminated soil. The study was conducted with soil obtained from the sector "The Farfana" (LF), Santiago, Chile (UTM 19H 0,331,733, 6,293,931), which was fortified with a mixture of 8 congeners of PCBs (8, 20, 28, 52, 101, 118, 138 and 180) on the other hand mixtures were prepared by adding to the soil fortified with PCB, different amounts of AO to obtain 4 levels of organic carbon (OC): 0; 5.6; 12 and 25%. A methodology of extraction with solvent and sonication was developed to estimate the pseudototal concentration of PCB in soil fortified. MOD from LF, Biosolid, Humex and commercial humic acid was used to assess the mobility of PCBs in soil columns. The experiments of mobility were carried out in glass columns packed with the different mixtures, the columns were connected to the cartridge of C-18 to perform solid phase extraction (SPE) continuously, and the collected eluates were taken to dryness and reconstituted with n-hexane with added internal standard for quantification of PCBs by GC-μECD. The results indicate that the soil has a sandy loam texture, with a high content of Cu and Mn, 8.09 pH in water and cation exchange capacity of 34 cmolkg-1. The results of the optimization of the methodology for the determination of pseudototal content of PCBs in soil, indicate that the sonication time is a factor involved significantly in the percentage of recovery of the analytes from the matrix, finding there an indirect relationship between the PCB analyzed and the recovery rate obtained, so for PCBs 28 and 180 the time required for a higher percentage recovery was 15 min, for the PCB 52 was 60 min, and for the PCB 101 was 20 min. The percentages did not follow a clear trend, which may be related to the matrix effect observed in the soil unfortified. With respect to the characterization of the DOM used for this study it was determined by IR spectroscopy (FTIR) and molecular spectroscopy (SUVA) that the distribution of the functional groups present on the MOD and its polarity depends on the origin of this. Spectroscopic analysis indicates a similarity in the FTIR spectra of the DOM, depending on their origin, being similar LF with commercial humic acid, and Humex with biosolids. Based on mobility experiments of PCBs through the soil profile it was determined that there are no significant differences according to the origin of the MOD, so that mobility can be influenced mainly by the MOD that exists naturally in the soil LF. Finally the results from the leaching of PCB congeners through soil with EO addition indicate that the amount leached was directly proportional to the amount of OA incorporated into the soil, being more eluted the PCBs with lower degree of chlorination. The determination of OC allowed to establish that the PCBs are mobilized by the MOD from soil, and the OA increase the mobility of these organic contaminants through the soil profile

Reproduction de : Thèse de doctorat : Sciences des agroressources : Toulouse, INPT : 2006. / Titre provenant de l'écran-titre. Bibliogr. 200 réf.

Thesis (Ph. D.)--Oregon State University, 2003. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph. D.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 136-153). Also available on the World Wide Web.

Soil is defined in a number of ways (Muller, 1960). It is regarded as the biochemically weathered portion of the regolith (Lyon et al., 1952:3) and as possessing, among other properties, certain "biological characteristics" (Joffe, 1936:37; Handley, 1954:1). From a zoological point of view Drift's (1951:6) definition of soil is adequate. [...]

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