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Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-02-02T17:29:36Z No. of bitstreams: 1 TESE_FINAL.AlineMansur.04092016.pdf: 3671406 bytes, checksum: 0deab42bbd5b80baf1c0a321d755a707 (MD5) / Made available in DSpace on 2017-02-02T17:29:36Z (GMT). No. of bitstreams: 1 TESE_FINAL.AlineMansur.04092016.pdf: 3671406 bytes, checksum: 0deab42bbd5b80baf1c0a321d755a707 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Fundação de Amparo à pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências- Geoquímica Ambiental. Niterói, RJ / As estações de tratamento de água (ETA) são projetadas para fornecer água continuamente, de maneira a atender a critérios de potabilidade. No entanto, além da água tratada e potável, essas estações são igualmente produtoras de resíduo, o material em suspensão decantado da água, reconhecido como resíduo de Estações de Tratamento de Água, ou resíduo de ETA. O descarte direto de resíduos de ETA em corpos d`água deve ser evitado, considerando que a essas descargas podem comprometer a qualidade da água, podendo gerar efeitos crônicos na comunidade aquática O Reservatório de Juturnaíba, considerado o segundo maior reservatório de água do estado do Rio de Janeiro, foi o repositório final dos resíduos produzidos por duas Estações de Tratamento de Água por cerca de 30 anos. Estes resíduos foram descartados nas margens do reservatório, podendo comprometer a qualidade da água e do sedimento do reservatório. Este estudo teve como objetivo avaliar se a disposição de resíduos de ETAs nas margens do reservatório causou contaminação no ambiente, através do estudo sobre mobilidade de metais (Al, Fe, Mn, Zn, Cr, Cu e Ni) entre os compartimentos: resíduos de ETAs, sedimentos superficiais e água do reservatório. Foram realizadas análises quantitativas e qualitativas dos resíduos de ETAs, bem como uma avaliação diagnóstica dos sedimentos superficiais adjacentes as áreas de descarte de resíduos. Através de modelos digitais de terreno construídos no software Surfer® e por equações matemáticas usando dados declarados pela empresa, foi possível calcular os volumes de resíduos presentes nas margens do reservatório, totalizando em cerca de 60.370 e 62.479 toneladas de resíduos em cada pilha de resíduo. Método de extrações de metais foram aplicados, para elucidar o teor pseudo-total (USEPA 3051A) e as frações geoquímicas dos metais (extração sequencial - BCR) nos resíduos de ETAs e nos sedimentos adjacentes a área de descarte. O fracionamento geoquímico de metais mostrou que existe uma a variação espacial entre os sedimentos localizadas próximos e distantes das áreas de descarte de resíduos. Os sedimentos localizados distantes da área de descarte não mostraram anomalias nas concentrações de metais, estando os metais Al, Fe, Zn e Cr associados predominantemente à fração residual (F4). O fracionamento do Al apresentou ser um bom traçador da presença de resíduos de ETA em sedimentos, já que apenas nos sedimentos localizados próximos aos resíduos, esse metal esteve predominantemente associado às frações prontamente mobilizáveis (F1+F2+F3) do sedimento, com elevadas concentrações na fração ácido-solúvel (F1). Assim, através do modelo de atenuação das concentrações pseudo-totais de Al no sedimento, aliado as avaliações de fracionamento geoquímico desse metal no sedimento, foi possível delimitar a área de abrangência da contaminação do sedimento, provenientes da dispersão espacial dos resíduos de ETAs. Experimentos usando microcosmos foram realizados para avaliar a dessorção de metais entre resíduo de ETA e a água do Reservatório, sob diferentes condições físico-químicas. Esses experimentos mostraram que o contato direto do resíduo com a água propicia a liberação de Al, Fe e Mn, e que a acidificação e o incremento de ácido húmico dissolvido na água favorece a dessorção do Al do resíduo. Conclui-se que a contaminação do sedimento por resíduos de ETAs está restrita a pequenas áreas localizadas próximas aos descarte de resíduo. No entanto, devido a proporção de Al associada as frações prontamente mobilizáveis do resíduo, a presença de resíduos de ETAs em contato direto com a água do reservatório, funciona como uma fonte pontual de Al para o ambiente. / Water treatment plants (WTP) are conceived to continuously produce clean water, responding to defined criteria of portability. However, besides treated and potable water, water treatment plants produce sludge resulting from decantation of the suspended matter that are disposed in the environment. The discharge of the water treatment residue into aquatic ecosystems may cause negative environmental impact on the natural water quality and chronic effects in the aquatic community. Juturnaíba Lake is an important water reservoir in Rio de Janeiro. For about 30 years, the residue generated by two Water Treatment Plants, were systematically discarded in two restricted areas in the Juturnaíba Reservoir edges. In direct contact with water, this residues may have been spread throughout the reservoir, affecting water and sediment quality. The aim of this study was to access the contamination of the Juturnaíba Reservoir, by evaluating the mobility of the metals (Al, Fe, Mn, Zn, Cr, Cu e Ni), between sludge, sediment, and water spatial and geochemical distribution of metals, mainly the Al, in the superficial sediments. Quantitative and qualitative analysis were performed, as a diagnostic evaluation of surface sediments adjacent waste disposal areas. The calculated mass of the residues piles are similar and respectively 60.3170 e 62.479. The residue mass was calculated based on the model terrain digital model and mathematical equations, which provided the following measures 60.370 e 62.479 tons in each piles of residue. Pseudo-total metal in sediment was assessed after aqua regia inverted digestion, with microwave assistance (EPA 3051A). The BCR sequential extraction procedure was applied, and geochemical fractions of Al, Fe, Mn, Zn, Cu, Cr e Ni were determined. The geochemical fractionation of metals showed that there is a spatial variation between near and far located sediments of residue disposal areas. In distant located sediments of the waste disposal area, the highest percentages Al, Zn, Fe and Cr was found in the residual fractions (F4), meaning that these metals were strongly bound to the sediments. Fractionation Al showed to be a good marker for the presence of ETA waste sludge, since only in the sediments located near the waste sludge, had aluminum predominantly associated with the mobile fractions (F1 + F2 + F3), with high concentrations in the acid-soluble fraction (F1). Through the model of attenuation of Al pseudo-total concentration in the sediment and along the geochemical fractionation assessments of Al in the sediments, it was possible to delimit the area of extent of sediment contamination, from the spatial dispersion of water treatment residue. Experiments using microcosms were performed to evaluate the desorption of metals from the residue and water reservoir under different physicochemical conditions. These experiments showed that the direct contact of the residue with water, promotes the release of Al, Fe and Mn, and that the acidification and the increase of humic acid dissolved in the water favor the desorption of Al present in the residue. The results show that the residue affected the sediment quality, although this contamination does not spread uniformly through the reservoir. It was concluded that the sediment contamination by water treatment residue is restricted to small areas located close to residue disposal. However, because the proportion of the Al associated with the mobility fractions, the presence of such residues in direct contact with the reservoir water,acts as a source of Al to the environment.

Le chlorométhane (CH3Cl) est un composé organique volatile responsable de plus de 15 % de la dégradation de l’ozone stratosphérique due aux composés chlorés. Il est produit majoritairement par les plantes vivantes ou en décomposition. Les bactéries capables d’utiliser le CH3Cl comme source de carbone pour leur croissance peuvent jouer un rôle de filtre dans les émissions de CH3Cl vers l'atmosphère. Ce processus biologique reste à quantifier dans l'environnement, notamment pour les sols forestiers considérés comme un puits majeur de ce composé.Dans les études environnementales, le gène cmu A est utilisé comme biomarqueur de la dégradation bactérienne du CH3Cl. Il code une chlorométhane méthyltransférase essentielle à la croissance bactérienne avec le CH3Cl parla voie cmu (pour chloromethane utilisation), la seule caractérisée à ce jour. Mon projet de thèse avait un double objectif : i) l’approfondissement des connaissances de l’adaptation au CH3Cl chez une bactérie méthylotrophe modèle, Methylobacterium extorquens CM4; ii) l’exploration de la diversité des bactéries CH3Cl-dégradantes de sols forestiers. L’étude RNAseq chez la souche CM4 a montré que la croissance avec le CH3Cl s'accompagne de différences dans la transcription de 137 gènes de son génome (6.2 Mb) par rapport à sa croissance sur le méthanol (CH3OH). Les gènes de la voie cmu, ainsi que d’autres gènes impliqués dans le métabolisme de cofacteurs essentiels à l’utilisation du CH3Cl par cette voie et eux aussi portés par le plasmide pCMU01 de la souche, en font partie. Les paralogues de ces gènes localisés sur le chromosome ne sont quant à eux pas différentiellement exprimés. En revanche, d’autres gènes du chromosome, potentiellement impliqués dans l’excrétion de protons produits lors de la déshalogénation (hppA), la régénération du NADP+ (pnt), ou le métabolisme du cofacteur tétrahydrofolate(gènes gcvPHT), le sont. L’étude de la diversité des bactéries CH3Cl-dégradantes de sol forestier de la réserve naturelle de Steigerwald (Allemagne) a été réalisée sur des microcosmes par une approche de « Stable Isotope Probing ». Les microorganismes capables d’assimiler le CH3Cl marqué au [13C] incorporent cet isotope lourd du carbone dans leur ADN. L'analyse des séquences amplifiées par PCR des gènes codant l’ARN 16S des fractions d'ADN enrichies en [13C] a permis de mettre en évidence de nouveaux phylotypes, du genre Methylovirgula et de l’ordre des Actinomycetales, distincts de ceux auxquelles les souches dégradant le CH3Cl isolées jusqu'ici sont affiliées. En revanche, les séquences du gène cmuA et d’autres gènes du métabolisme méthylotrophe obtenues par PCR à partir de l'ADN enrichi en [13C] sont très proches de celles des souches CH3Cl-dégradantes connues. Les résultats obtenus suggèrent ainsi que des bactéries ayant acquis par transfert horizontal les gènes de dégradation de la voie cmu ou ne possédant pas de gène cmuA contribuent au filtrage biologique du CH3Cl des sols forestiers. A l'avenir, le couplage de différentes méthodes moléculaires et des approches culturales visera à découvrir de nouvelles voies microbiennes de l’utilisation du CH3Cl, et à caractériser l’abondance et la diversité des métabolismes impliqués dans la dégradation du CH3Cl dans les sols et d'autres compartiments environnementaux. / Chloromethane (CH3Cl) is a volatile organic compound responsible for over 15% of stratospheric ozone degradation due to chlorinated compounds. It is mainly produced by living and decaying plants. Bacteria utilizing CH3Cl as sole carbon and energy source for growth were shown to be involved in the filtering of CH3Cl emissions to the atmosphere. This biological process remains to be quantified in the environment, especially for forest soil, a major CH3Cl sink. The cmuA gene is used as a biomarker of bacterial CH3Cl degradation in environmental studies. It encodes a CH3Cl methyltransferase essential for bacterial growth by the cmu (chloromethane utilization) pathway for growth with CH3Cl and the only one characterized so far. My thesis project had a double aim: i) In depth studies of CH3Cl adaptation of a model methylotrophic bacterium, Methylobacterium extorquens strain CM4; ii) Exploration of bacterial CH3Cl-utilizers in forest. An RNAseq study of strain CM4 has shown that growth with CH3Cl leads to a difference of transcription of 137 genes in its 6.2 Mb genome compared to growth with methanol (CH3OH). Among those, genes of the cmu pathway and other genes involved in the metabolism of essential cofactors for CH3Cl utilization by this pathway, are all plasmid pCMU01-encoded. Paralogous genes located on the chromosome were not differentially expressed. On the other hand, other chromosomal genes potentially involved in extruding protons generated during CH3Cl deshalogenation (hppA), NADP+ regeneration (pnt), or in the cofactor tetrahydrofolate metabolism (gcvPHT) were differentially expressed. The diversity of CH3Cl-degrading bacteria in forest soil of the German natural park of Steigerwald was studied in microcosms using stable isotope probing. Microorganisms able to assimilate labeled [13C]- CH3Cl incorporate this heavy carbon isotope in their DNA. Sequence analysis of the PCR-amplified 16S RNA encoding gene from [13C]-DNA fractions uncovered phylotypes of the genus Methylovirgula and of the order of the Actinomycetales, which were not associated with bacterial CH3Cl degradation so far. In contrast, PCR-amplified sequences of cmuA and other genes of methylotrophic metabolism were closely related to known CH3Cl-degrading isolates. These results suggest that bacteria containing genes of the cmu pathway acquired by horizontal gene transfer as well as bacteria lacking the cmu pathway contribute to biological filtering of CH3Cl in forest soil. Future experiments coupling molecular and culture methods will aim to discover new CH3Cl-degrading pathways and to characterize the abundance and diversity of CH3Cl-degradation metabolism in soil and other environmental compartments.