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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Hunters or gardeners? Plant-microbe interactions in rootless carnivorous Utricularia / Hunters or gardeners? Plant-microbe interactions in rootless carnivorous Utricularia

SIROVÁ, Dagmara January 2012 (has links)
Various aspects of the ecophysiology of rootless carnivorous Utricularia plants were assessed, with focus on nutrient acquisition and mutualistic interactions within trapping organs. The study includes extracellular enzyme measurements, the evaluation of commensal microbial community structure and function, stable isotope labelling to determine plant carbon allocation, and ion chromatography analyses of trap fluid composition
92

Gradients in benthic community structure and bioturbation potential along the Nordic Seas continental margin

Shields, Mark Aiden January 2008 (has links)
The Nordic Seas region marks a transitional zone between the temperate North Atlantic Ocean and the polar Arctic Ocean. The influence of contrasting fluxes of organic matter on benthic community structure and function within the deep waters of the region were investigated. Samples of the macrofaunal community were collated throughout the region employing a standardised method. In the summer of 2002, during the RRS James Clark Ross 75 cruise, replicated samples were obtained with the SMBA multiple corer and the USNEL boxcorer from four stations located at similar sampling depths along a latitudinal transect at the Norwegian Sea continental margin. Additional replicated samples were obtained with a megacorer at six stations located along two bathymetric transects across the Norwegian Sea continental margin in the summer of 2005 during the RRS James Clark Ross 127 cruise. Contrasting fluxes of organic matter influenced benthic community structure, functional ecology and bioturbation potential. Species known to adopt the feeding strategy of the sub-surface storage of organic matter occurred in areas characterised by a seasonal input of organic matter. Species richness and diversity was highest at the Svalbard Margin, located within the marginal ice zone. Bathymetric patterns of macrofaunal biomass were comparable with previously reported global patterns. However, bathymetric patterns of macrofaunal abundance were higher than global patterns. The previously reported rapid subduction of organic matter by the sipunculan Nephasoma sp. and associated deep burrow networks on the Voring Plateau was linked to the species Nephasoma lilljeborgi. It is proposed that N. lilljeborgi is an ecosystem engineer.
93

Avaliação do teor de carbono orgânico total na qualidade da água: aplicação na radiofarmácia / Evaluation of total organic carbon content in the quality of the water: application in radiopharmacy

BENEDETTI, STELLA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:53Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
94

Atributos físicos e químicos de um latossolo vermelho cultivado com cana-de-açúcar, com a conservação do palhiço e aplicações de torta de filtro e vinhaça

Silva Junior, Gilberto Leite da [UNESP] 12 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-12Bitstream added on 2014-06-13T20:39:16Z : No. of bitstreams: 1 silvajunior_gl_me_ilha.pdf: 751239 bytes, checksum: 3d40f0de35ad6d9b9cf19b65f73836f0 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Com o aumento das áreas onde o canavial é colhido sem a queima prévia, novos estudos se fazem necessários para medir as alterações que poderão ocorrer no ambiente de adoção dessa prática, associando a decomposição do palhiço da cana-de-açúcar juntamente com o uso de subprodutos agroindustriais. Assim, o presente trabalho teve como objetivo avaliar a influência do uso ou não de vinhaça, palhiço e torta de filtro sobre indicadores da qualidade física e química de um Latossolo Vermelho, cultivado com cana-de-açúcar, no município de Sud Mennucci, SP. Para isso foram testados cinco tratamentos: solo descoberto e sem aplicação de resíduos (sem preservação do palhiço); solo com preservação do palhiço e sem aplicação de resíduos (vinhaça e torta de filtro); solo com preservação do palhiço e aplicação de vinhaça; solo com preservação do palhiço e aplicação de torta de filtro; solo com preservação do palhiço e aplicações de vinhaça e torta de filtro. Utilizou-se o delineamento experimental de blocos ao acaso com cinco repetições. Foram avaliados os atributos físicos: porosidade do solo; granulometria, densidade do solo; distribuição e estabilidade dos agregados em água e, químicos: pH, fósforo, matéria orgânica, capacidade de troca catiônica, potássio, cálcio, magnésio, acidez potencial, alumínio e, calculadas a soma de bases e saturação por bases, nas camadas de 0- 0,10 m, 0,10-0,20 m e 0,20-0,40 m. Os resultados foram analisados efetuando-se a variância e teste de Tukey a 5% de probabilidade. Foram avaliadas também a biometria e qualidade tecnológica pré-colheita da cultura da cana soca. A aplicação de vinhaça e torta de filtro sobre o palhiço, em primeira soca, não influenciou nos atributos físicos do solo... / The increase of the areas where sugarcane is harvested without prior burning further studies are needed to measure the changes that can occur due to the adoption of these practices involving straw sugar cane decomposition and the use of agroindustrial subproducts. The aim of this work was to evaluate the physical and chemical influence of using vinasse, straw and filter cake on the chemical quality of a Red Latosol (Oxisol) cultivated with sugar cane, located at Sud Mennucci city, São Paulo, Brazil. Five treatments were tested: bare soil without waste application and preservation of straw; soil and straw preservation without waste application (vinasse and filter cake); soil and straw preservation with vinasse application; soil with straw preservation and filter cake application; soil and straw preservation with vinasse and filter cake application. Randomized blocks, with five replications, were used as experimental design. The physical and chemical attributes were evaluated and submitted to ANOVA and Tukey test at 5% probability. The physical attributes were: soil porosity, particle size distribution, soil bulk density, distribution and aggregate stability in water, and chemical were: pH, P, organic matter, cation exchange capacity, K, Ca, Mg, H+Al, Al, sum of bases and bases saturation in the layers from 0 to 0.10 m; 0.10 to 0.20 and 0.20 to 0.40 m. Were also evaluated biometrics technology and quality pre-harvest sugar cane second cutting.The application of vinasse and filter cake on straw, about the second cutting, did not influence the physical attributes of the soil or the length, number and mass of stems and technological quality of the same, the quality of soil under study was influenced by the application vinasse and filter cake on straw, just improving the levels of phosphorus and potassium increases in phosphorus... (Complete abstract click electronic access below)
95

Qualidade do solo medida por indicadores fÃsicos em Ãrea com aplicaÃÃo de resÃduo de caju / Soil quality measurement in physical indicators in area with application of waste cashew

RÃgis dos Santos Braz 15 March 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O avanÃo das fronteiras agrÃcolas e a intensificaÃÃo do uso da terra devido à necessidade de atender à demanda por alimentos e fibras tÃm feito com que o solo perca sua qualidade, pois em muitos casos nÃo se adotam prÃticas de conservaÃÃo, causando grandes perdas da qualidade ambiental. A aplicaÃÃo de resÃduos orgÃnicos, como o resÃduo de caju, sobre a superfÃcie do solo intensifica a atividade biolÃgica no solo, à medida que esse material se incorpora, cujos produtos de decomposiÃÃo e de sÃntese proporcionam alteraÃÃes na geometria porosa da matriz do solo. Diante disso, esse trabalho objetivou avaliar a qualidade do solo medida por indicadores fÃsicos em Ãrea com aplicaÃÃo de resÃduo de caju. Para tal, foram coletadas amostras com estrutura preservada e nÃo preservada para a realizaÃÃo das seguintes determinaÃÃes: anÃlise granulomÃtrica, densidade do solo, densidade de partÃculas, curva de retenÃÃo de Ãgua no solo, resistÃncia do solo à penetraÃÃo e determinaÃÃo do intervalo hÃdrico menos limitante. Foi adotado o delineamento em blocos ao acaso (DBC), quatro blocos e cinco tratamentos. Sendo os tratamentos T1 = 0, T2 = 16 t ha-1, T3 = 32 t ha-1, T4 = 48 t/ha e T5 = 64 t/ha. Para verificar a normalidade dos dados foi aplicado o teste de Kolmogorov-Smirnov e anÃlise de variÃncia (ANOVA) para testar a hipÃtese. Os valores de densidade do solo estiveram acima do estabelecido para solos arenosos. A densidade de partÃculas esteve prÃxima aos valores estabelecidos para solos minerais. Observou-se a predominÃncia de macroporoso sobre os microporos. A resistÃncia do solo à penetraÃÃo nÃo ultrapassou o limite crÃtico de 2,0 MPa. O intervalo hÃdrico menos limitante teve a capacidade de campo como limite superior e ponto de murcha permanente como limite inferior. PorÃm, nenhumas dessas variÃveis citadas anteriormente tiveram diferenÃa estatÃstica significativa. As curvas de retenÃÃo de Ãgua no solo tiveram comportamento tÃpico de solos arenosos, observando-se uma reduÃÃo da capacidade de retenÃÃo de Ãgua nos tratamentos onde o resÃduo foi aplicado. As doses de resÃduo de caju nÃo surtiram efeitos significativos sobre as variÃveis analisadas, exceto na curva de retenÃÃo de Ãgua no solo. / The advancement of the frontiers agricultural, due to the necessity to meet the demand for food and fiber, causes loss of soil quality, because in many cases it is not adopt conservation practices, and this has caused great losses of environmental quality. The application of organic waste, such as cashew residue, on the soil surface enhances the biological activity in soil, as that material is incorporated, and decomposition and synthesis cause changes in the geometry of the porous matrix of the soil. Therefore, this study aimed to evaluate the physical quality of soil in the area of application of doses of cashew residue, analyze how these doses interfere on the soil condition and propose alternatives for maintaining or improving its quality. Samples were collected with preserved structure and not preserved structure for the achievement of the following determinations: particle size analysis, bulk density, particle density, soil water retention curve, soil resistance to penetration and least limiting water range. In this work were adopted a DBC, five treatments in four blocks. The treatments T1 = 0, T2 = 16 t ha-1, T3 = 32 t ha-1, T4 = 48 t/ha and T5 = 64 t/ha. To verify the normality of the data was applied the Kolmogorov-Smirnov test and analysis of variance (ANOVA) to test the hypothesis. The values of soil density was above the established for sandy soils. The particle density was close to the values established for mineral soils. There is a predominance of macropores compared to micropores. The resistance to penetration did not exceed the critical threshold of 2.0 MPa. The least limiting water range obtained field capacity as the upper limit and permanent wilting point as the lower limit. However, none of these variables mentioned above were statistically significant. The soil water retention curves had typical behavior of sandy soils, observing a reduced capacity for water retention in treatments where residue was applied. Doses of cashew residue had no effect on the significant variables, except the water retention curve.
96

Avaliação do teor de carbono orgânico total na qualidade da água: aplicação na radiofarmácia / Evaluation of total organic carbon content in the quality of the water: application in radiopharmacy

BENEDETTI, STELLA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:53Z (GMT). No. of bitstreams: 0 / Radiofármacos são preparações farmacêuticas que possuem um radionuclídeo em sua composição. Cerca de 95% deles são utilizados com finalidade diagnóstica e em sua maioria são administrados por via parenteral, requerendo o uso de água purificada (AP) e para injeção (API) nos processos de produção, controle de qualidade e pesquisa de novos radiofármacos. A produção de radiofármacos no Brasil deve atender às Boas Práticas de Fabricação (BPF), RDC n. 17/2010 e RDC n. 63/2009 da ANVISA e requisitos de qualidade definidos pelas farmacopeias vigentes. Considerando que os volumes dos lotes de fabricação de radiofármacos são reduzidos, de algumas dezenas a centenas de mililitros, e a sua validade é de algumas horas a alguns dias, frequentemente tem sido utilizados sistemas purificadores de uso laboratorial para a produção de AP e API nas radiofarmácias. A determinação de carbono orgânico total (COT) é um dos requisitos a serem atendidos na avaliação da qualidade de AP e API e o seu limite é de 500 μg L-1. O objetivo deste estudo foi validar o método analítico de COT que combina reações de acidificação e de oxidação química do carbono para análise de carbono inorgânico (CI) e carbono total (CT), na análise de AP e API, avaliar o desempenho de sistemas de purificação de uso laboratorial para a produção de AP e API e comparar com a API adquirida de fornecedores externos. Utilizou-se um analisador de carbono modelo TOC-Vwp acoplado a um amostrador automático modelo ASI-V, ambos da marca Shimadzu® e controlados por software TOC Control-V e frascos de 40 mL lavados com HNO3 15%, com soluções de reagente oxidante (Na2S2O8 0,5 mol L-1) e acidificante (H3PO4 3,0 mol L-1), soluções de COT/CT (C8H5O4K) e CI (Na2CO3 e NaHCO3) nas concentrações 100-1000 μg L-1. Foram avaliados os parâmetros de validação de método: conformidade do sistema, robustez, repetibilidade, precisão intermediária, exatidão, linearidade e limites de detecção e quantificação. O desempenho de 5 sistemas de purificação foram avaliados, com amostragem de AP e API de 6 pontos (3 de AP e 3 de API) e foram analisados COT, condutividade, pH, contagem de aeróbios totais e endotoxina bacteriana (somente para API). As melhores condições de análise foram 2 mL de oxidante, 3% de acidificante, tempo de integração da curva de CT de 10 minutos e 3 minutos para CI. As curvas analíticas de CT e CI foram lineares nas faixas de concentrações analisadas, com a soma residual dos mínimos quadrados (r2) maior que 0,997. Os resultados de repetibilidade apresentaram valores entre 0,40 4,40%, a precisão intermediária por sua vez apresentou a seguinte variação, 0,65 a 4,63% e exatidão apresentou valores na faixa de 96,76-112,52%. Os limites de detecção (LD) e quantificação (LQ) foram 31,83 e 106,11 μg L-1 e 59,16 e 197,22 μg L-1, para CT e CI, respectivamente. A avaliação de desempenho dos purificadores indicam que um procedimento adequado de limpeza do reservatório de água é importante para manter a concentração de COT em cerca de 100 μg L-1. A análise de COT/CI pode ser utilizada como indicador da necessidade de manutenção do sistema purificador. Algumas API embaladas apresentaram COT acima de 500 μg L-1. O monitoramento de COT durante a avaliação de desempenho dos sistemas de uso laboratorial acoplados a reservatórios indicou que eles são equipamentos adequados para obtenção de AP e API em radiofarmácia. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
97

The Role of Dissolved Organic Matter on the Mobilization of Arsenic from a Legacy Mine Tailings Site

Bozeman, Lauren R., Bozeman, Lauren R. January 2018 (has links)
Legacy mine sites are of concern due to their prevalence and associated environmental and human health risks. The United States Bureau of Land Management estimates as many as 500,000 abandoned mine sites in the US (BLM, 2017). Sites requiring costly management and long-term response to the environmental hazardous risks can be designated to a National Priority List (NPL) by the Environmental Protection Agency (EPA) under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) (EPA, 2017). One such site, located in Central Arizona, is the Iron King Mine Humboldt Smelter Superfund Site (IKMHSSS). The site was designated to the NPL in 2008 due to concerns regarding the size of the tailing pile, the proximity of contaminated materials to the town of Dewey-Humboldt and waterways, and the dangerous concentrations of arsenic (As) and lead (Pb) of the tailings (EPA, 2017). Remediation efforts have been ongoing since the designation of the site to the NPL, including sampling, yard soil removal, and distribution of information to the local community regarding risks from the site. The University of Arizona Superfund Research Program (UA SRP) has conducted greenhouse and phytostabilization studies of the site in an attempt to understand the processes and mechanisms employed to stabilize the tailings materials as well as reduce dust emissions from the tailings to the town of Dewey-Humboldt (Gil-Loaiza et al., 2016). This effort has successfully demonstrated a reduction of dust emissions (Sáez, 2016), however chemical changes to the tailings due to phytostabilization are the focus of this research. This work attempts to ascertain whether adverse effects from the method of phytostabilization are observed in the pore waters of the tailing material, in particular the potential for contamination of water sources by mobilized As through chemical or microbiological means. Recent studies have proposed potential mechanisms that can promote mobilization of As by dissolved organic matter (DOM) (Mladenov et al., 2015). Heterotrophic microbial respiration under O2 limited conditions can cause the reduction of Fe3+ to Fe2+, enhancing desorption or dissolution of As from Fe containing minerals (Hasan et al., 2007). Additionally, DOM competes with As for sorption sites at mineral surfaces (Grafe et al., 2002). In this study, batch and column experiments were used to investigate the mechanisms of sequestration and release of As in compost amended mine tailings. Mine tailings were reacted in triplicate in the presence and absence of DOM using plain tailings and radiated tailings for microbiological control and under anoxic and oxic conditions at timescales from ranging from 3 to 900 hours for batch experiments and 1 to 900 pore volumes in column experiments. The highest As release to pore waters was observed under anoxic conditions in the presence of DOM both with microbial activity inhibited and uninhibited through 60Co gamma irradiation after 3 and 910 h of reaction. The release of As from batch experiments was lowest in the control treatment with no DOM added to tailings in both anoxic and oxic treatments after 24 h. Column flow-through experiments were also carried out to better understand the kinetic biogeochemistry of the tailings interacting with DOM. Columns were completed under suboxic conditions to best mimic field scenarios. To test the effect of microbes, control tailing samples were sterilized by 60Co gamma irradiation prior to flowing DOM. Pore volumes (PV) were collected using fractionation equipment from 1 to 900 PVs. The release of As was highest in the presence of DOM after approximately 40 PVs when As release began increasing to its maximum release of 50 μmol l-1. No significant difference between irradiated and non-irradiated tailings was observed in either irradiated or non-irradiated tailings. Lowest release of As to effluent solutions was in the absence of DOM. These results were consistent with the findings from batch experiments. Batch and column experiments show that DOM influences the mobilization of As from mine tailings, and demonstrates the potential risk to proximal ground water resources in the absence of attenuation processes between the oxidized tailings and groundwater.
98

Geochemical controls on arsenic release into groundwaters from sediments: in relation to the natural reactive barrier

Berube, Michelle M. January 1900 (has links)
Master of Science / Department of Geology / Saugata Datta / Elevated levels of dissolved arsenic (As), iron (Fe) and manganese (Mn) are seen in the shallow, anoxic groundwaters of southeast Bangladesh on the Ganges- Brahmaputra- Meghna River delta. Over the past decade the mechanisms of As release have been widely debated. It is understood that As can sorb onto Fe-bearing minerals and can be subsequently released when reactions, such as microbially driven processes, occur. This study takes a multi disciplinary approach to understand the extent of the natural reactive barrier along the Meghna River and to evaluate the role of the natural reactive barrier in As sequestration and release in groundwater aquifers. River water and groundwater interactions occur in the hyporheic zone, which is defined as the transient subsurface region where river water and groundwater mix. The natural reactive barrier can develop within the hyporheic zone, where Fe-bearing minerals accumulate with a potential for As sorption, along with reworking and re-deposition of sediments along the riverbank. Shallow sediment cores, and groundwater and river water samples were collected from the east and west banks of the Meghna River in Jan. 2016. Groundwater and river water samples were tested for total dissolved Fe, Mn, and As concentrations; δ₂H, δ₁₈O isotopic ratios. Fluorescence spectroscopic characterization of groundwater organic matter provided insight into the hydro-geochemical reactions active in the groundwater and the hyporheic zone. Eight sediment cores of ~1.5 m depth were collected ~10 m away from the edge of the river. Vertical solid-phase concentration profiles of Fe, Mn, and As were measured by four different methods (hand-held XRF, and ICP-OES analysis of 3 digestions: aquaregia (HNO₃: HCl 1:3), 1.2 M HCl, and 1 M NaH₂PO₄ + 1 M L-ascorbic acid extractions). Enrichment of solid phase Fe, Mn, and As and the presence of possible Fe and Mn oxides in the sediments illustrate the existence of an natural reactive barrier at this reach of the Meghna. HCl extractions of sediment revealed solid-phase As accumulation along the west riverbank reaching concentrations of ~1500 mg/kg. Aqueous geochemical results showed the highest dissolved As concentrations in shallow wells (<30 m depth), where organic matter was fresh, humic-like, and aromatic. Humic-like dissolved organic matter present in the groundwater may enhance Fe oxide dissolution. Microbial reduction of organic matter prompts the reduction of Fe³⁺ to Fe²⁺, causing As to mobilize into groundwater. This study quantified the extent of As accumulation in the sediments along a 1 km stretch of the Meghna River. These findings contribute to the understanding of geochemical processes involved in As release into groundwaters from sediments within a fluvial deltaic environment.
99

Infiltration, runoff and particle mobilization on canola fields at langgewens experimental farm, Mooreesburg, Western Cape

Mmachaka, Thandi Nthabiseng January 2013 (has links)
Magister Scientiae - MSc / The primary origin of this project is due to a high demand for freshwater supply in the Berg Water Management Area (WMA). Most of the Berg WMA`s freshwater supply does not live up to the high ecological standards. This is mainly due to high sediments loading in the Berg River which is one of the water supplies to the Berg WMA. The project was conducted on a small-scale catchment at Langgewens experimental farms in Swartland district. The focus of this study was to address some of the hydrological processes active in the research catchment: infiltration, run-off and sediment mobilization on different soil types under wheat and canola vegetation cover. This was done to investigate the origin of sediments in the Berg River. Considering the results, one might conclude that the decayed root systems from the canola and wheat vegetation covers, organic matter content, soil cracks, slope orientation, and soil composition, all played a major role in influencing the ability of the soil to absorb the simulated rainfall. Because the infiltration was calculated using the difference between the incoming simulated rainfall and the measured run-off, there was an inverse relationship between run-off and infiltration. When run-off was low, the infiltration was high and vice versa. iv Factors that governed sediment mobilisation within the ring area are micro topography within the ring area, the slope gradient and vegetation covers. Considering the results, vegetation cover played a pivotal role and it must be maintained at all times. It is advisable that the land users leave crop residual cover behind after the annual harvest and not expose the land surface in bare form for too long as this will generate more run-off and increase sediment mobilisation. The analyses showed that wheat crop protects the soil from rain drop impact than on canola crop.
100

Dynamique des micropolluants organiques au cours du traitement biologique de résidus solides : lien entre caractérisation du résidu, localisation des micropolluants organiques au sein des compartiments du résidu et processus (sorption, biodégradation) / Dynamic of organic micropollutants during biological treatment of solid waste : link between characteristics of the waste, location of organic micropollutants within waste compartment end processes (sorption, biodegradation)

Aemig, Quentin 15 December 2014 (has links)
De nombreux déchets organiques urbains, industriels et agricoles sont considérés comme des produits résiduaires organiques (PRO). Ils sont potentiellement recyclables en agriculture comme amendement ou fertilisant pour le sol avec selon le type de déchet la mise en œuvre de traitements biologiques (digestion anaérobie, compostage). Du fait de l'utilisation de produits chimiques, les PRO contiennent des micropolluants organiques (µPO) particulièrement quantifiés dans les boues d'épuration. Ces µPO peuvent être toxiques pour les humains et les écosystèmes bien que les concentrations dans les milieux aquatiques soient très faibles (ng-µg.L-1). La plupart de ces µPO ont un fort impact sur l'environnement. Lors des traitements biologiques des boues d'épuration, l'élimination des µPO dépend de deux processus (sorption et biodégradation) eux-mêmes contrôlés par les propriétés physicochimiques de la matière organique et des µPO et les microorganismes présents. La forte sorption et le piégeage des µPO ou leur biodégradation dans la matrice boue lors des traitements minimisent le risque de transfert à l'eau ou à la faune/flore après l'épandage des boues. Cette thèse se propose d'étudier le devenir de différents µPO (hydrocarbures aromatiques polycycliques (HAP), nonylphénols (NP) et produits pharmaceutiques) lors du traitement de boues par digestion anaérobie et compostage en lien avec le devenir de la matière organique et l'affinité des µPO pour certaines fractions de cette matière organique. L'objectif est de mieux comprendre les mécanismes qui régissent l'élimination des µPO et in fine d'estimer comment améliorer le procédé pour limiter les transferts au continuum sol/eau/biote. Dans un premier temps, un protocole de caractérisation de la matière organique a été couplé avec un dosage de µPO au cours d'une incubation anaérobie, sur une matrice modèle (boue) et sur des composés modèles (HAP, NP). Les résultats ont montré que les µPO dissipés se situent dans les compartiments les plus accessibles et les plus dégradables de la matière organique et que cette dissipation est pilotée par la dégradation de la matière ; de plus, un phénomène de vieillissement a été observé pour des molécules dopées. Les résultats démontrent que les µPO étudiés ici ont une affinité pour les matières organiques complexes de type humiques. Lors des incubations, seule la moitié de la matière organique est caractérisée. Le protocole de caractérisation de la matière organique a été modifié pour aller plus loin dans la caractérisation « matière » mais aussi en vue d'une application sur la localisation des µPO tout au long d'un système de traitement comprenant digestion et compostage. Ce protocole a donc été revu afin de pouvoir caractériser des matrices de type lignocellulose. Ce protocole a été appliqué à des échantillons issus de la digestion anaérobie et du compostage de boues en laboratoire. Ces procédés sont capables d'éliminer une partie des µPO ; le couplage des deux augmentant le taux d'élimination. L'évolution des fractions matière reflètent la dégradation de la matière organique lors des traitements. De plus, le devenir des µPO étudiés est piloté par le devenir de la matière organique nous permettant de proposer des stratégies d'optimisation de leur dissipation.Les résultats acquis permettent de déterminer des taux d'abattement des µPO lors des traitements des boues mais aucune information n'est donnée quant aux mécanismes précis d'élimination. Les mêmes traitements ont été menés en utilisant des molécules marquées au 14C. Les résultats obtenus sur trois molécules (fluoranthène, NP et sulfaméthoxazole) montrent que les µPO ne sont pas minéralisés lors de la digestion anaérobie. Lors du compostage des boues digérées, une minéralisation du NP apparaît lors de la phase de maturation. Diverses hypothèses peuvent alors expliquer l'élimination constatée au cours des traitements sans molécule marquée : métabolites ou résidus non extractibles sont formés. / Animal manures, urban organic wastes including sewage sludge, food processing and other industrial wastes are considered as organic wastes that are potentially recycled in agriculture as soil amendment or fertilizer after biological treatment like anaerobic digestion and composting.Due to the use of chemicals and industrial activities, these organic wastes contain organic micropollutants, particularly quantified in sewage sludge. These micropollutants are a family of organic compounds which may be toxic for humans or ecosystems even though their concentrations in aquatic environments are usually low (µg to ng.L-1). Most of them have huge impacts on environment (e.g. some of them are endocrine disruptors that can feminize fishes in rivers with concentrations of few ng.L-1).During biological treatments of sewage sludge, micropollutants elimination depends on two processes (sorption and biodegradation) that are driven by physicochemical properties of organic matter and micropollutants and microorganisms. Strong sorption and trapping of organic micropollutants or their biodegradation in sludge matric during anaerobic digestion and composting can minimize their transfer into water or biota after spreading.This thesis aims at studying the fate of organic micropollutants (polycyclic aromatic hydrocarbons (PAHs), nonylphenols (NPs) and pharmaceuticals compounds) during sludge treatment by anaerobic digestion and composting in link with the fate of organic matter and the micropollutants affinity for some organic matter fractions. The objective is to better understand the mechanisms which control the micropollutants elimination and estimate how to improve the process to minimize environmental impact.First, a method for sludge organic matter characterization is coupled to organic micropollutants quantification during a model batch process (anaerobic incubation), on a model matrix (sludge) and model compounds (PAHs, NPs). Results show that dissipated micropollutants are located in more accessible and degradable fraction of organic matter and that dissipation is driven by organic matter degradation; furthermore, ageing phenomenon is observed for spiked compounds. Results show that micropollutants have strong affinity for complex organic matter (humic-like substances).During incubations, the quantity of characterized organic matter corresponds only to 50 % of chemical oxygen demand. A modified protocol for characterizing organic matter is set up to go further on organic matter characterization but also to apply it to localization of organic micropollutants. This protocol is also modified in order to characterize other organic matrices (compost).The new protocol is applied to samples from anaerobic digestion and composting of sludge at lab-scale. Anaerobic digestion and composting are able to eliminate organic micropollutants. Coupling both processes increases micropollutants removal. The fate of organic matter pools during processes mimics the fate of organic matter. A link between the fate of organic matter and the fate of organic micropollutants is determined during anaerobic digestion and composting.The results allow determining organic micropollutants removal during anaerobic digestion and composting of sludge but no information is given about the removal mechanisms. Anaerobic digestion with composting is set up at lab-scale with the use of organic 14C labelled micropollutants. The results with three molecules (fluoranthene, sulfamethoxazole, nonylphenols) show that organic micropollutants are not mineralized during anaerobic digestion. During composting, only nonylphenols are mineralized during the maturation phase. Hypothesis about micropollutants removal are the production of metabolites or the formation of non-extractable residues.

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