The impact of liming (10 t ha-1 of calcitic and dolomitic limestone, separately) on the soil solution and soil matrix was investigated in an acidic metal-contaminated soil from Sudbury, ON. A soil mesocosm experiment was performed; columns were leached with simulated rainwater and the soil solution collected at various locations throughout the soil column. The dissolution rate of calcitic limestone used for this experiment was found to be approximately double that of the dolomitic limestone investigated. Calcium and Mg released during limestone dissolution migrated through the soil profile to the Bf-BC interface. The addition of limestone increased the pH and decreases the bioavailability of Ni, Cu, Co, Cd, As, Ba, Mn, and Zn the LFH horizon. Amending acid, contaminated soils with calcitic or dolomitic limestone has profound effects on soil solution chemistry.

Made available in DSpace on 2014-06-11T19:29:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-14Bitstream added on 2014-06-13T19:17:18Z : No. of bitstreams: 1 araujo_mm_me_sjrp.pdf: 1487042 bytes, checksum: 0cb591f27f66e82e9cdb8ae34683ea7d (MD5) / Instituto de Pesquisas Tecnologicas / Este trabalho apresenta o estudo experimental do comportamento térmico do inseticida hexaclorociclohexano, para avaliar se a técnica de dessorção térmica é indicada no processo de descontaminação do solo para este tipo de contaminante. Para a realização deste estudo, amostras do inseticida foram submetidas a diversas temperaturas com diferentes tempos, no intuito de avaliar as perdas de massa e verificar a possível geração de contaminantes por meio das emissões gasosas durante o aquecimento. Os resultados indicaram que no aquecimento do inseticida houve liberação de cloro e possível decomposição do inseticida e das impurezas presentes na amostra. Observou-se também a formação de bifenilas policloradas, furanos, benzeno, clorobenzeno, dentre outros, e a volatilização dos compostos presentes na amostra. A concentração dos isômeros do inseticida quando submetido à temperatura de 350°C diminuiu após quatro dias de aquecimento, ao ponto de ficar próximos dos valores orientadores para solo estabelecidos pela CETESB. Pode-se concluir que o comportamento térmico do inseticida HCH mostrou-se satisfatório para a aplicação da técnica de dessorção térmica, pois sua concentração diminuiu significativamente nos experimentos realizados. Verifica-se que a aplicação da técnica exige o tratamento das emissões gasosas geradas / This paper presents the experimental study of the thermal behavior of the insecticide hexachlorocyclohexane, to evaluate the technique of thermal desorption is indicated in the process of decontamination of soil for this type of contaminant. For this study, samples of the insecticide were subjected to different temperatures at different times, in order to evaluate the mass losses and check the possible generation of contaminants through gaseous emissions during heating. The result indicates that the heating of the insecticide was release of chlorine and possible decomposition of the insecticide and the impurities in the sample. We also observed the formation of polychlorinated biphenyls, furans, benzene, chlorobenzene, among others, and evaporation of the compounds present in the sample. The concentration of the insecticide isomers when subjected to a temperature of 350 °C decreased after four days of heating, the point of being close to the guiding values for soil established by CETESB. It can be concluded that the thermal behavior of the insecticide HCH was satisfactory for the application of the technique of thermal desorption, since its concentration decreased significantly in the experiments. It appears that the technique requires the treatment of gaseous emissions generated

Orientador: Ieda Ap. Pastre Fertonani / Banca: Marisa Spirandeli Crespi / Banca: Vera Aparecida de Oliveira Tiera / Resumo: Este trabalho apresenta o estudo experimental do comportamento térmico do inseticida hexaclorociclohexano, para avaliar se a técnica de dessorção térmica é indicada no processo de descontaminação do solo para este tipo de contaminante. Para a realização deste estudo, amostras do inseticida foram submetidas a diversas temperaturas com diferentes tempos, no intuito de avaliar as perdas de massa e verificar a possível geração de contaminantes por meio das emissões gasosas durante o aquecimento. Os resultados indicaram que no aquecimento do inseticida houve liberação de cloro e possível decomposição do inseticida e das impurezas presentes na amostra. Observou-se também a formação de bifenilas policloradas, furanos, benzeno, clorobenzeno, dentre outros, e a volatilização dos compostos presentes na amostra. A concentração dos isômeros do inseticida quando submetido à temperatura de 350°C diminuiu após quatro dias de aquecimento, ao ponto de ficar próximos dos valores orientadores para solo estabelecidos pela CETESB. Pode-se concluir que o comportamento térmico do inseticida HCH mostrou-se satisfatório para a aplicação da técnica de dessorção térmica, pois sua concentração diminuiu significativamente nos experimentos realizados. Verifica-se que a aplicação da técnica exige o tratamento das emissões gasosas geradas / Abstract: This paper presents the experimental study of the thermal behavior of the insecticide hexachlorocyclohexane, to evaluate the technique of thermal desorption is indicated in the process of decontamination of soil for this type of contaminant. For this study, samples of the insecticide were subjected to different temperatures at different times, in order to evaluate the mass losses and check the possible generation of contaminants through gaseous emissions during heating. The result indicates that the heating of the insecticide was release of chlorine and possible decomposition of the insecticide and the impurities in the sample. We also observed the formation of polychlorinated biphenyls, furans, benzene, chlorobenzene, among others, and evaporation of the compounds present in the sample. The concentration of the insecticide isomers when subjected to a temperature of 350 °C decreased after four days of heating, the point of being close to the guiding values for soil established by CETESB. It can be concluded that the thermal behavior of the insecticide HCH was satisfactory for the application of the technique of thermal desorption, since its concentration decreased significantly in the experiments. It appears that the technique requires the treatment of gaseous emissions generated / Mestre

Orientador: Lucia Regina Durrant / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-10T12:19:48Z (GMT). No. of bitstreams: 1 Santos_EderdaCostados_D.pdf: 13848159 bytes, checksum: 4e9d5c77145b57ba74b6fa2e9c764982 (MD5) Previous issue date: 2008 / Resumo: Hidrocarbonetos, metais pesados e defensivos agrícolas são poluentes que oferecem alto risco à saúde humana e de animais. No entanto, estão constantemente sendo introduzidos no meio ambiente como resultado de atividades petroquímicas, industriais, agrícolas e do próprio estilo de vida moderna, necessitando que processos de remedição sejam empregados para a sua completa eliminação. A biorremediação é um processo mediado por microrganismos que possui grande potencial para recuperação de ambientes contaminados, mas a falta de informação sobre fatores que regulam o crescimento e o metabolismo das comunidades microbianas em ambiente poluído limita sua implementação. Técnicas aplicadas à bioquímica do solo e análises metaproteômicas podem avaliar as atividades microbianas e identificar as alterações fisiológicas decorrentes da exposição a agentes tóxicos. O objetivo do presente estudo foi monitorar parâmetros bioquímicos tais como: respiração, biomassa microbiana, qCO2 e atividades de enzimas específicas envolvidas nos principais ciclos biogeoquímicos, assim como a identificação dos perfis metaproteômicos de solos impactados. De uma maneira geral, os hidrocarbonetos afetaram todos os parâmetros bioquímicos avaliados, sendo que na presença de metais pesados tais efeitos foram mais acentuados. Para a realização das análises metaproteômicas foi elaborado um protocolo para extração direta de proteínas do solo que permitiu a separação de 1600 spots bem resolvidos em géis 2D-PAGE. Os perfis metaproteômicos revelaram proteínas qualitativamente e quantitativamente expressadas diferentemente em decorrência da presença dos contaminantes. As análises metaproteômicas dos distintos solos expuseram proteínas expressadas em comum, envolvidas no sistema de resposta a estresse ambiental, tais como: chaperonas, fatores de elongação EF-Tu, superóxido dismutases, proteínas de transporte da superfamília ABC, Alquil hidroperóxidos redutases, peptidil prolil cis-isomerases, bem como outras específicas do metabolismo. Estes resultados demonstram que a metaproteômica é uma ferramenta robusta que pode auxiliar no entendimento das comunidades microbianas complexas, revelando alterações dinâmicas da população frente a alterações no ecossistema. Com base na literatura internacional este é o primeiro estudo metaproteômico ¿in situ¿ de solos contaminados / Abstract: Hydrocarbons, heavy metals and agricultural defensives are high risk pollutants to human health. These pollutants are constantly introduced into the environment as a result of petrochemical, industrial, agricultural activities and our modern life style, requiring remediation processes that are used to their complete elimination. Bioremediation is a process carried out by living organisms which has great potential for the recuperation of contaminated environments, but the lack of information about the factors that regulate growth and metabolism of microbial communities in polluted environments limits its implementation. Soil biochemistry techniques and metaproteomics analyses can assess the microbial activity and identify the physiological changes resulting from exposure to toxic agents. The objective of this study was to determine biochemical parameters such as: respiration, microbial biomass, qCO2 and activities of specific enzymes involved in major biogeochemical cycles, as well as the identification of metaproteomics profiles of contaminated soil. In general hydrocarbons affected all the biochemical parameters evaluated, and the presence of heavy metals caused an increase in these parameters. A protocol for direct extraction of soil proteins that allowed the separation of more than 1600 spots settled in 2D PAGE gels was developed. The metaproteomics profiles revealed, qualitatively and quantitatively, that proteins were expressed differently due to the presence of these contaminants. Metaproteomics analyses of different exposed soils showed proteins expressed in common, involved in the response to environmental stress, such as: chaperones, elongation factors, EF Tu, superoxide dismutases, ABC transport protein superfamily, alkyl hydroperoxide redutases, peptidyl prolil cis isomerases, as well as the other specific of the metabolism. These results show that metaproteomics is a robust tool that can assist in the understanding of complex microbial communities, revealing the dynamic of the population opposed to changes in the ecosystem. Based on the international literature this is the first "in situ" metaproteomic study of contaminated soils / Doutorado / Doutor em Ciência de Alimentos

Ce travail de recherche porte sur l'optimisation des procédés de lavage de sol permettant le traitement des sites contaminés par des métaux lourds. Cette étude se concentre sur le cycle complet de ce type de traitement, incluant la possibilité de réutilisation et un traitement adapté de la solution de lavage de sol utilisée. La conception et l'exploitation d'un procédé de lavage de sol sont étudiées dans le but d'optimiser leur coût et leur efficacité. Dans ce but, les paramètres et la configuration du réacteur utilisé pour ce procédé sont étudiés en détail à travers des tests à l'échelle du laboratoire, et les cinétiques sont simulées par une modélisation mathématique. Les échantillons de sol utilisés au cours de cette étude proviennent de terres agricoles présentant une forte contamination en cuivre. Parmi plusieurs agents chélateurs de la famille des aminopolycarboxylates, il a été choisi d'utiliser l'acide éthylènediamine-N, N'-disuccinique (EDDS) pour sa biodégradabilité - largement rapportée dans la littérature – et son efficacité importante d'extraction des métaux lourds, y compris du cuivre. Le travail bibliographique a permis d'identifier les deux paramètres cruciaux pour l'optimisation du procédé de lavage de sol : le rapport molaire EDDS : Cu et le rapport liquide-solide (L/S). Des tests réalisés dans un réacteur à agitation continue (RAC) en fonctionnement discontinu ont permis d'étudier l'influence de ces deux paramètres sur le rendement et la cinétique d'extraction du cuivre. L’augmentation du rapport molaire EDDS : Cu a permis une meilleure amélioration de l'efficacité du procédé, comparée à l'augmentation du rapport L/S. Par ailleurs, les tests réalisés en discontinu ont clairement mis en évidence une première étape cinétique rapide au début du traitement, suivie d'une seconde étape d'extraction plus lente jusqu'à la fin du traitement. Il a donc été formulé un modèle empirique basé sur deux termes cinétiques. Les paramètres du modèle ont été calibrés puis validés grâce à deux séries de données expérimentales différentes. Ce modèle permet d'abord d'évaluer la validité de l'hypothèse d'un procédé reposant sur deux étapes cinétiques différentes. Cela représente aussi un nouvel outil pour prévoir l'efficacité du procédé en fonction de l'évolution du ratio molaire EDDS : Cu et du temps de traitement. Les coûts d'exploitation du procédé ont été minimisés en étudiant différentes configurations de traitement. En particulier, deux configurations en réacteur piston ont été analysées et comparées à celle en RAC. Les réacteurs pistons ont été simulés en utilisant plusieurs réacteurs en série et en variant les temps de rétention et le fractionnement de l'injection de la solution de lavage de sol. Comparés à la configuration en RAC, les résultats obtenus en réacteur piston ont montré une amélioration du rendement et de la cinétique d'extraction du cuivre, ainsi qu'une réduction de la quantité de solution de lavage utilisée. Pour finir, un procédé électrochimique a été mis en place pour le traitement et la récupération de la solution d'EDDS utilisée. Des tests en réacteur discontinu ont permis d'optimiser les paramètres de ce procédé (densité de courant, pH et conductivité de la solution de lavage de sol). La solution récupérée a ensuite été utilisée pour d'autres étapes de lavage de sol. Les résultats obtenus ont prouvé l'efficacité du traitement électrochimique pour la récupération de la solution d'EDDS, et permettent d'envisager l'application de cette technique pour réduire le coût des procédés de lavage de sol utilisant l'EDDS / The object of the present research work is the optimization of soil-washing processes applied to heavy metal contaminated soils. The work focuses on the whole cycle of these treatments, including the possible recovery and the proper disposal of the used washing solution. Both the design and the exploitation of a soil washing treatment are investigated, in order to maximize their efficacy, in terms of cost and process efficiency. At this aim process parameters and reactor configurations are studied in details through lab-scale tests, and the observed kinetics are simulated through mathematical modeling. Soil samples used for the experimental activity were collected from an agricultural field located in Southern Italy, mainly contaminated by copper. Among several Aminopolycarboxylate (APC) chelating agents, Ethylenediamine-N,N'-disuccinic acid (EDDS) was selected, for its recognized biodegradability, widely reported in literature works, and its efficiency as extracting agent towards several heavy metals, including Cu. Literature review allowed determining the two most important process parameters to be investigated for washing optimization. The two parameters were identified as EDDS : Cu molar ratio and liquid to soil ratio (L/S). In order to investigate the effect of these parameters on process kinetics and Cu extraction yield, batch washing tests in continuous-stirred tank reactor configuration (CSTR) were carried out. EDDS : Cu molar ratio increase was found to be able to enhance process efficiency more than L/S increase. Batch tests clearly displayed a first fast kinetic step at the beginning of the treatment, followed by a second slower kinetic extraction step, which lasted until the end of the treatment. According to this observation, an empirical mathematical model based on two-kinetic terms was formulated. Model parameters were firstly calibrated and then validated using two different sets of experimental data. The derived mathematical model was useful to assess the validity of the two-kinetic steps process hypothesis, and to provide a tool for process efficiency prediction depending on EDDS : Cu molar ratio and treatment time length. Exploitation costs of the process were minimized studying different treatment configurations. In details two Plug-Flow configurations were analyzed and compared to the CSTR one. The two Plug-Flow configurations were simulated using several reactors in series, varying the detention time of the reactors, and fractionating the injection of the washing solution. Achieved results displayed improvements in terms of Cu extraction yield and process kinetic for the tested Plug-Flow conditions compared to the CSTR one, and showed that the use of a Plug-Flow reactor allows to reduce the amount of required washing solution. Finally, an electrochemical process was tested for the treatment and the recovery of the spent EDDS solution. Batch tests were carried out to optimize electrochemical process parameters (e.g. current density, washing solution pH and conductivity). The recovered solution was also used for a multi-washing test. Results proved the effectiveness of the electrochemical treatment for EDDS solution recovery and its potential application as technique for EDDS-enhanced soil washing costs reduction

Les biochars sont au cœur de la lutte contre les changements globaux. Ils constituent aussi un enjeu pour la gestion durable des sols contaminés. Ces travaux ont été conduits afin de mieux comprendre les effets du biochar sur la mobilité des métaux dans les sols et leur transfert vers les plantes. Une série d’expériences de complexité croissante ont été conduites, impliquant un biochar obtenu par pyrolyse de bois à 450 °C, et deux sols, l’un acide et l’autre alcalin, contaminés par Cd, Pb et Zn suite à l'activité d'une fonderie. Une gamme d’espèces végétales aux réponses contrastées vis-à-vis des métaux a été testée. Des essais de sorption en batch et de lixiviation en colonnes couplés à une caractérisation microscopique et spectroscopique du biochar ont été réalisés, ainsi que des expériences de croissance végétale en vases de végétation, en rhizotrons et en lysimètres. Les résultats démontrent que les phases minérales carbonatées du biochar jouent un rôle prépondérant dans l'immobilisation des métaux. Elles interviennent dans la sorption directe des métaux à la surface du biochar par co-précipitation. Leur dissolution contribue également à l'augmentation du pH du sol, conduisant à une rétention accrue des métaux à la surface des particules du sol. Le biochar modifie le transfert des métaux vers la plante en diminuant la disponibilité des métaux, mais également en diminuant la mobilité de cations majeurs et en modifiant la surface racinaire développée par la plante. Une diminution du transfert du métal vers les parties aériennes de la plante a généralement été observée avec Lolium perenne ou Zea mays, alors qu'une augmentation du prélèvement de Cd et Zn par l'hyperaccumulateur Noccaea caerulescens a été mise en évidence. En conclusion, le biochar contrôle la mobilité des métaux dans les systèmes sol-plante grâce à une série de mécanismes différents. Au plan pratique, le biochar favorise les stratégies de phytostabilisation et de phytoextraction des métaux dans les sols contaminés / Biochars play a central part in the mitigation of global changes. They also represent a challenge for the sustainable management of contaminated soils. This work was conducted in order to better understand the effects of biochar on the mobility of metals in soils and their uptake by plants. A range of experiments was set up following a gradual increase of complexity, with a wood-derived biochar obtained by pyrolysis at 450 °C and two soils, acidic or alkaline, contaminated by Cd, Pb and Zn from smelter activity. Various plant species with contrasting response to metals were tested. Batch sorption and column leaching experiments coupled to microscopic and spectroscopic characterization of biochars were conducted, together with plant growth experiment in pots, rhizoboxes and lysimeters. Results demonstrate that biochar's carbonated mineral phases play a dominant role in the immobilization of metals. They lead to metals direct sorption on the surface of biochar by co-precipitation. Their dissolution also contributes to the increase of soil pH, leading to an increased retention of metals on soil particles. Biochar alters the transfer of metals to the plants by decreasing the availability of metals, but also by decreasing the mobility of major cations and by modifying root surface. A decrease of metal transfer to the shoots was generally observed with Lolium perenne or Zea mays, while an increase of the uptake of Cd and Zn by the hyperaccumulator Noccaea caerulescens was evidenced. In conclusion, biochar controls the mobility of metals in soil-plant systems through a range of different mechanisms. From a practical point of view, biochar promotes both strategies of phytostabilization and phytoextraction of metals in contaminated soils

The contamination of soils, with polycyclic aromatic hydrocarbons (PAHs), remains a widespread environmental concern. In the past two decades, many physical, chemical and biological methods have been developed and evaluated for the degradation of PAHs. However, due to their low aqueous solubility, high sorption affinity, hydrophobicity and recalcitrance, the environmental remediation of PAHs in soil continues to be economically challenging. In addition to PAH contamination, the presence of oxygenated derivatives of PAHs (OPAHs), in soils, has increasingly become a concern due to their greater toxic properties compared to parent PAH compounds. To date, no investigations on OPAH-remediation methods have been presented in the literature. The use of zero-valent metals (ZVMs) has been reported for several halogenated contaminants in solution systems, but the effectiveness of ZVM to degrade sorbed PAHs and OPAHs has been rarely addressed. This present research focuses on the development of a combined technique for the feasible desorption and degradation of PAHs and OPAHs in soils. PAH and OPAH degradation efficiency, using activated magnesium (Mg) metal combined with an ethanol-ethyl lactate cosolvent (1:1 ratio), was initially examined in soil-free systems. This metal/cosolvent system demonstrated adequate degradation (above 80%) for high-molecularweight (HMW) PAHs, which were subsequently converted into hydroaromatic compounds; while OPAHs were degraded and converted into hydroxylated or hydrogenated derivatives. Further soil-free studies revealed that the degradation rate was affected by the surface or reactive iv sites of the metal and that optimum degradation efficiency were obtained with Mg ball milled with graphite (Mg/C). In a bench-scale feasibility test, the efficacy of this system was assessed on a soil spiked with a mixture of three HMW PAHs compounds and three OPAHs compounds with amounts ranging from 0.033 mmol to 0.060 mmol. The experimental results show that 2 mL of an ethanol-ethyl lactate solvent mixture resulted in 58% to 85% extraction efficiency for the selected contaminants in 1 g of spiked soil, followed by 64 - 87% degradation efficiency of the extracted contaminants with 4.11 mmol of the activated metal. This activated-Mg/cosolvent system can be considered as a promising alternative method for ex situ remediation of PAH and OPAH-contaminated soils.

La phytoextraction représente une solution environnementale prometteuse face au problème de contamination des sols en éléments traces (É.T). La présente étude s’intéresse aux différences intra et interspécifiques (S. purpurea, S. dasyclados, S. miyabeana) de trois cultivars de saule lorsqu’ils sont utilisés pour la phytoextration de six É.T. (As, Cd, Cu, Ni, Pb et Zn). Les objectifs sont (i) décrire les variations intrapécifiques du cultivar FISH CREEK (S. purpurea) lorsqu’il est utilisé pour la phytoextraction sur deux sites d’étude; et (ii) décrire les variations intra et interspécifiques des cultivars FISH CREEK (S. purpurea), SV1 (S. dasyclados) et SX67 (S. miyabeana) lorsqu’ils sont utilisés pour la phytoextraction d’un site d’étude. Les indicateurs de variations intra et interspécifiques sélectionnés sont les suivants : la biomasse totale, les concentrations en É.T. extraits et les facteurs de translocation (x ̅ pondérée des conc. É.T. dans les parties aériennes / conc. É.T. dans les racines). La contribution des propriétés du sol (degré de contamination, caractéristiques physicochimiques) à la phytoextraction a été évaluée. Les cultivars ont présenté des variations interspécifiques significatives. Cependant, les variations intraspécifiques sur un site d’étude étaient parfois plus importantes que celles mesurées entre les trois différents cultivars. L’amplitude des variations intraspécifiques que présentent le cultivar FISH CREEK sur deux sites d’étude est attribuée à l’influence du pH, de la minéralogie et au contenu en matière organique, lesquelles diffèrent entre les deux sites. Il a aussi été démontré que la phytoextraction des É.T. n’était pas systématiquement corrélée de façon positive avec le degré de contamination. Cela suggère que les concentrations en É.T. mesurées dans le sol ne peuvent pas expliquer à elles seules la variation des concentrations mesurées dans les tissus. L’implication des mécanismes de rétention dans le sol semblent être davantage responsable des variations observées. La compartimentation des É.T. suggère que le saule est efficace pour l’extraction du Cd et du Zn et qu’il est efficace pour la phytostabilisation de l’As, du Cu, du Ni, et du Pb. En ce qui concerne les quantités extraites, le cultivar FISH CREEK semble le plus performant dans la présente étude. / Phytoextraction is a promising solution to the environmental problem of soil contamination by trace elements (TE). This study focuses on intra and interspecific differences (S. purpurea, S. dasyclados, S. miyabeana) of three willow cultivars used for phytoextration of six TE (As, Cd, Cu, Ni, Pb and Zn). The objectives are (i) describe the interspecific variations of FISH CREEK cultivar (S. purpurea) used for phytoextraction on two study sites; and (ii) describe intra and interspecific variations of FISH CREEK (S. purpurea) SV1 (S. dasyclados) and SX67 (S. miyabeana) cultivars used for phytoextraction of a study site. The selected indicators of intra and interspecific variations are : total biomass, TE concentrations extracted and translocation factors (x ̅ weighted TE conc. in aerial parts / conc. TE in the roots). The contribution of soil properties (contamination level, physicochemical characteristics) to phytoextraction was evaluated. The cultivars showed significant interspecific variations. However, intraspecific variations were sometimes more important than variations measured between the three different cultivars grown on one study site. The magnitude of intraspecific variations of FISH CREEK cultivar grown on two study sites is attributed to the influence of pH, mineralogy and organic matter content, which differ between the two sites. It was also shown that the phytoextraction of TE was not consistently correlated positively with the contamination level. This suggests that the TE concentrations measured in soil can not by themselves explain the variation in the measured tissue concentrations. The involvement of retention mechanisms in soil appear to be more responsible for the observed variation. ET compartmentalization suggests that the willow is effective for Cd and Zn extraction and is effective for As, Cu, Ni, and Pb phytostabilisation. Regarding the amount extracted, cultivar FISH CREEK seems the most effective cultivar in this study.

L'augmentation de la dégradation des sols et ses conséquences sur les services écosystémiques nécessite le développement de stratégies de restauration de ces sols. La constitution de Technosols, résultant de l’assemblage de sols pollués et de déchet industriels, est une approche innovatrice pouvant à la fois permettre de restaurer les sols et de recycler des sous-produits industriels. Des études récentes ont mis en évidence que les Technosols pouvaient assurer des services écosystémiques tels que la production primaire. Toutefois, notre connaissances des autres services écosystémiques rendus par les Technosols tels que les cycles biogéochimiques est limitée. En raison de la contribution significative des communautés microbiennes aux cycles biogéochimiques dans les sols, l’objectif de ce travail de thèse était l’effet du type de Technosol sur les communautés microbiennes et plus particulièrement les communautés fonctionnelles impliquées dans le cycle de l’azote. Dans ce contexte, (i) la densité et la diversité de la communauté bactérienne totale, (ii) la densité de la communauté crenarchéenne ainsi que (iii) la densité et les activités des communautés nitrifiante et dénitrifiante ont été étudiées dans deux types de Technosols différents. Les résultats obtenus montrent que la diversité et la composition de la communauté bactérienne des deux Technosols n'étaient pas significativement différentes entre elles, et similaires à celles de ‘sols naturels’, les Proteobacteria étant le phylum dominant (50-80%). La densité de la communauté bactérienne oxydant l’ammonium était non seulement plus importante que celle des crenarcheae qui oxyde l’ammonium, mais est également corrélée avec l'activité potentielle de nitrification suggérant ainsi que les bactéries sont responsables de l’oxydation de l’ammonium dans les Technosols. La densité des dénitrifiants et de la communauté oxydant l’ammonium sont du même ordre de grandeur que celles observées dans les sols agricoles. L’analyse de la distribution de l'activité et de la densité des communautés nitrifiante et dénitrifiante dans les différents horizons des Technosols montre un effet négatif de la profondeur, cet effet étant plus marqué que l’effet du type de Technosol étudié. Les propriétés physico-chimiques des Technosols et la densité de la communauté bactérienne oxydant l’ammonium sont corrélés à l'activité de nitrification alors que l'activité de dénitrification était contrôlée principalement par les propriétés physico-chimiques des Technosols, et dans une moindre mesure par la densité de la communauté dénitrifiant possédant le gène nirS. L'estimation de la stabilité fonctionnelle du processus de dénitrification vis-à-vis de périodes stress hydrique et thermique a montré que les Technosols présentaient une plus haute résistance et une meilleure résilience que des sols remédiés par traitement thermique uniquement. Ce travail souligne le potentiel des Technosols à assurer les services écosystémiques tels que le cycle de l’azote, ainsi que leur forte capacité à résister et à se remettre de stress environnementaux. Tout ceci semble donc indiquer que la construction de Technosols est une technologie prometteuse qui pourrait permettre la restauration de friches industrielles et le recyclage des déchets industriels / Increasing soil degradation and its consequences on overall ecosystem services urge for restoration strategies. Construction of Technosols through assemblage of treated soil and industrial wastes is an innovative technology for the restoration of polluted land and re-use of industrial by-products. Recent studies have evidenced that Technosols could support ecosystemic services such as primary production but the knowledge about other soil functions, such as biogeochemical cycling, is limited. Due to the significant contribution of microbial communities to soil functioning, this PhD work was carried out to study the effect of the type of Technosol on microbial communities with a focus on functional guilds involved in N cycling. For this purpose, the abundance and diversity of the total bacterial community and the abundance of crenarchaeal community together with the abundance and activities of the nitrifying and denitrifying communities were investigated in two types of Technosols. Results demonstrated that diversity and composition of the bacterial community were similar to ‘natural soils’ and were not significantly different between the two Technosols with Proteobacteria being the dominant phylum (50-80%). The bacterial ammonia oxidizers were greater in number than crenarchaeal ammonia oxidizers but also correlated to the potential nitrification activity suggesting that bacteria are the dominant ammonia oxidizers in Technosols. The abundance of both the ammonia oxidizers and the denitrifiers were in the same range than that observed in other soil systems. Analyses of the vertical distribution of the activity and abundance of N-cycling communities in the Technosols showed a significant depth-effect, which was more important than the Technosol type-effect. Technosols physicochemical properties and the abundance of the bacterial ammonia oxidizers were the main drivers of the nitrification activity whereas the denitrification activity was controlled mainly by the Technosols physicochemical properties and, to a minor extent, by the abundances of the nirS denitrifiers. The estimation of the functional stability of the denitrification process against the heat-drought stresses revealed that Technosol exhibited the high resistance and resilience in comparison to the thermally treated soil. This work highlighted the potential of constructed Technosols to ensure the N cycling ecosystem services, along with a high capacity to resist and recover from environmental stresses, suggesting that construction of Technosols is a promising technology and a solution for the restoration of industrial wastelands and waste recycling

O presente trabalho tem por objetivo monitorar o agrotóxico Mancozeb no solo em diferentes sistemas de plantios de tomate utilizando a metodologia de decomposição dos ditiocarbamatos (DTCs) com geração de dissulfeto de carbono (CS2). Este método é amplamente utilizado na determinação dos resíduos de DTCs em alimentos, tendo sido adaptado para trabalhar com amostras de solo artificiais e reais. O método foi avaliado utilizando amostras contaminadas artificialmente a partir de uma amostra de solo controle, proveniente da Amazônia. A contaminação foi realizada com uma solução de campo (2 g.L-1 em água) do agrotóxico Manzate 800 (Mancozeb). A partir do momento em que foram determinadas as condições ideais de operação do método de decomposição dos DTCs, analisou-se o teor de Mancozeb em amostras reais, provenientes de uma área cultivada com tomate, no Município de São José de Ubá (RJ), sob sistemas de Plantios Convencional, Mínimo e Direto. Foi possível constatar a presença de teores de Mancozeb nas amostras reais de solo em estudo, coletadas nas profundidades 0 - 5 cm; 5 - 10 cm; 10 - 20 cm e 20 - 40 cm. Os resultados mostraram que os solos provenientes dos sistemas convencional e mínimo apresentaram, na camada superficial, um teor de Mancozeb de (7,44 mg.kg-1 e 5,70 mg.kg-1) superior ao obtido no sistema direto, que apresentou teores de (1,14 mg.kg-1 e 1,95 mg.kg-1) de Mancozeb / The present work aims to evaluate Mancozeb pesticide monitoring on the ground in different systems of tomato seeding using the methodology of decomposition of dithiocarbamates (DTCs) with carbon disulfide (CS2) generation. This method is widely used to determinate DTCs residues in foods and it was adapted to work with artificial and real soil samples. The method was evaluated using artificially contaminated samples from a control soil sample proceeding from Amazônia. The contamination was carried out with a field solution (2 g.L-1 in water) of Manzate 800 (Mancozeb). From the moment the operational conditions of decomposition method of the DTCs were determined, the content of Mancozeb was analyzed in real samples proceeding from an area cultivated with tomato, in São Jose de Ubá city (Rio de Janeiro), under Conventional, Minimum and Direct systems of seeding. It was possible to evidence Mancozeb content in the real samples collected in 0 - 5 cm; 5 -10 cm; 10 - 20 cm and 20 - 40 cm depths. The results showed the soil samples proceeding from conventional and minimum systems (7.44 mg.kg-1 e 5.70 mg.kg-1) seeding presented Mancozeb content on the ground surface in higher level than the one obtained in direct system (1.14 mg.kg-1 e 1.95 mg.kg-1)