Dissertations / Theses: 'Humic matter'

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Fearing, David Andrew. "Process options for the treatment of humic rich waters." Thesis, Cranfield University, 2004. http://dspace.lib.cranfield.ac.uk/handle/1826/128.

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Seasonal periods of high rainfall have led to difficulties in removing sufficient natural organic matter (NOM) to meet trihalomethane (THM) standards, and hence better or alternative treatments are required. Typically bulk water parameters such as dissolved organic carbon (DOC) and UV absorbance at 254nm (UV254) are used to optimise treatment processes. Here the isolated fraction character and molecular weight (MW) distribution was used in conjunction with bulk water parameters to tailor process options for the treatment of humic rich waters. Three options for the removal of NOM were proposed. A staged coagulation based on the optimisation of isolated fractions. The results showed that although no significant reduction in DOC or UV254 was observed filter breakthrough was significantly reduced. Secondly a novel magnetic ion exchange process (MIEX®) for the removal of NOM was evaluated. The results showed that a combination of MIEX® and ferric reduced the THM formation potential (THMFP) by more than 50% and lower MW compounds that are known to be untreated by conventional coagulation were reduced. This option was also shown to be the most robust option for the treatment of waters with differing quality caused by seasonal changes and different catchments. Finally the addition of a range of adsorbents including carbons, hydroxides and clays to both the raw water and the isolated low MW fractions showed that an increase in DOC and UV254 removal was achievable. This was proposed as a post coagulation option during times of high organic loading. All processes provide viable options for the treatment of humic rich waters during times when current processes are being challenged and having difficulty meeting THM standards.

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De, Nobili Maria. "An investigation of the relative importance of soil organic matter and fresh substrates for microbial survival in soil." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251940.

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Collins, Michael Robin. "Removal of aquatic organic matter and humic substances by selected water treatment processes." Diss., The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_382_sip1_w.pdf&type=application/pdf.

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Watanabe, Cláudia Hitomi. "Fate, behavior and ecotoxicology of silver nanoparticles : interactions with natural organic matter in aquatic systems /." Sorocaba, 2020. http://hdl.handle.net/11449/192324.

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Orientador: André Henrique Rosa
Resumo: When introduced in environment, manufactured nanoparticles (NPs) can interact with biotic and abiotic molecules yielding a transformed NP usually coated with these molecules (natural coating). These different forms of the NPs should be considered as new materials because them distinct properties from the released NPs forms. In fact, these in situ transformations of the NPs have relevant impacts on their toxicological effects, having new or additional risks still not studied. This project aims to determine, understand and predict the impact of natural molecules in the transformations and bio-effects of Ag NPs, widely used as antibacterial agents. Despite the growing interest and use of these NPs, the gathered knowledge on their environmental consequences is still scarce, since the large majority of the studies do not consider the effect of the presence of natural coatings around the particles. In fact, most of the studies do not even determine the effects of the presence of manufactured coatings. Generally, NPs manufacturers add ionic or polymeric coatings to improve their mobility and stabilization in terms of size. Although the possible effects of these manufactured coatings in the NPs behavior there is not systematically studied about their impact. This project aims to overcome the current uncertainty about the environmental safety of manufactured coated NPs, and explore the impact of natural molecules on their environmental risk. The project objectives are: i) characterize... (Resumo completo, clicar acesso eletrônico abaixo)
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Hertkorn, Norbert. "Molecular level structural analysis of natural organic matter and of humic substances by NMR spectroscopy." kostenfrei, 2006. http://mediatum2.ub.tum.de/doc/606006/document.pdf.

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Kuo, Ching-Jey. "FACTORS AFFECTING PARTICLE GROWTH AND RELATED ORGANIC MATTER REMOVAL DURING ALUM COAGULATION (SIZE DISTRIBUTION, TRIHALOMETHANES, HUMIC)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183866.

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Effects of several important source-related and operation-related factors on particle formation and growth as well as potential particle and dissolved organic matter removal by alum coagulation are described. Two representative natural water sources, with low turbidities and high concentrations of dissolved organic matter, and one commercially available crystalline silica, with defined characteristics, were employed to establish initial aquatic particle and dissolved organic matter conditions. Six experimental variables utilized for evaluation include initial pH, initial turbidity, applied pre-ozonation dose, alum dose, flocculation time and sedimentation time. A bench-scale experimental apparatus with capabilities of ozonation, coagulation, sedimentation and membrane filtration was employed to conduct a series of selected experiments. Each factor investigated in this research proves to be able to inpart, individually or collectively, statistically significant effects on particle formation and growth during alum coagulation. While the addition of model particles shows significant enhancement in particle growth, it fails to demonstrate significant improvement in the removal of dissolved organic matter. On the contrary, effects of pH and alum dose on particle formation and growth are accompanied by corresponding effects on the removal of dissolved organic matter. Pre-ozonation of dissolved organic matter renders the dissolved organic matter more hydrophilic by increasing the number of carboxylic acid functional groups. This phenomenon can significantly improve or impede particle growth as well as dissolved organic matter removal during alum coagulation, depending on raw water chemistry and other operational factors. Alum coagulation under all of the conditions investigated in this research is demonstrably more effective in removing aquatic humic susbtances with higher apparent molecular weights and fewer carboxylic acid functional groups, as opposed to those with lower apparent molecular weight and more carboxylic acid functional groups. The predominant removal mechanisms were found to occur at the beginning stage of the coagulation process; that is, the rapid mixing period. The remaining dissolved organic matter and humic substances can form significant amounts of trihalomethanes upon reaction with chlorine.

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Bell, Nicholle Georgina Anneke. "Molecular-scale characterisation of humic substances using isotope-filtered nD NMR spectroscopy." Thesis, University of Edinburgh, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.716584.

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Humic substances (HS), the complex mixture of organic molecules produced by microbial and abiotic degradation of plant and animals residues, are the major components of organic matter in soil and natural waters. As such, they are vital to the integrity of soil, play important roles in nutrient biogeochemical cycling and determine the mobility and fate of both nutrients and contaminants. How HS enact their varied roles, however, is largely unknown due to the lack of comprehension of their molecular make-up. What is known is that they contain aromatic (e.g. phenols, condensed aromatics) and aliphatic (e.g. carbohydrates, lipids) molecules with prevailing carboxyl and hydroxyl functionalities. As for other complex chromatographically inseparable mixtures, high-resolution analytical techniques such as Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) as well as Nuclear Magnetic Resonance (NMR) spectroscopy have been applied to study HS composition at the molecular level. While FT-ICR MS can provide molecular formulae, it is only NMR that can unveil structures. Until now, however, very few unambiguous structures of individual molecules have emerged from standard NMR experiments. This is because purposely designed multidimensional NMR experiments are required to achieve ‘spectroscopic separation’ where chromatography fails. In this work, ‘spectroscopic separation’ was accomplished with the aid of chemical modification in the form of 13C methylation of COOH and OH groups. 13C containing tags allow the observation of signals only from molecules carrying these tags. In combination with purposelydesigned isotope-filtered NMR experiments, these tags act as spies reporting on their surrounding structure. This is achieved by utilising scalar and dipolar couplings to transfer the polarisation between protons and carbons of the 13CH3O groups and nuclei of the parent molecules. The necessary spectral resolution is attained using 3D/4D NMR experiments. This approach provides access to an array of correlated chemical shifts of HS molecules and represents a paradigm shift in the use of tags in investigations of complex mixtures: instead of focusing only on the tags, they are used to obtain structural information from the molecules they are attached to. The compounds at the centre of this investigation are the phenols of HS. These molecules are thought to be important in many of the key processes in organic matter rich soils, particularly peat. For example, their accumulation is thought to impair the activity of extracellular enzymes essential for the degradation of peat HS. Understanding the nature and source of phenols would provide a more fundamental framework for rationalising their role in peat, as well as other carbon rich soils. The developed methodology was initially tested on model mixtures containing 3 or 9 phenolic compounds before applying it to a operational fraction of HS, fulvic acid, extracted from a Scottish raised peat bog. For this fulvic acid, over 30 major phenolic molecules/moieties were identified, many of which can be directly traced to the flora prevalent in the vicinity of the sampling site. For the first time in 150 years of HS research, a novel analytical methodology has yielded unambiguous structural information, providing the first steps towards understanding the various roles of HS in natural systems.

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Stubbins, Aron Paul. "Aspects of aquatic CO photoproduction from CDOM." Thesis, University of Newcastle Upon Tyne, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369787.

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Paczkowska, Joanna. "Phytoplankton drivers in a marine system influenced by allochthonous organic matter – the Baltic Sea." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126389.

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Climate change scenarios predict that seawater temperature and precipitation will increase in the Baltic Sea region during the next century. In the northern part of the Baltic Sea, increasing inflows of the terrestrial allochthonous dissolved organic matter (ADOM) are expected to be a major consequence of elevated rainfall, which can alter light and nutrient availability for phytoplankton. The aim of my thesis was to elucidate effects of ADOM on phytoplankton production, community, size-structure and nutritional strategy along offshore south-north gradients in the Baltic Sea, as well as in estuarine systems exposed to seasonal variation in river discharge. Field studies, a mesocosm experiment and a modeling study were used to explore these issues. Results from the field studies and mesocosm experiment illustrated that the nutritional strategy, size-structure and cellular pigment content of the phytoplankton were governed by changes in ADOM, and thus in light and nutrient availability. A summer study along an offshore south-north gradient showed that the proportion of mixotrophic phytoplankton increased towards the north. In this area the concentrations humic substances (proxy for ADOM) were high, while the light availability and phosphorus concentrations were relatively low. The phytoplankton cells responded to reduced light availability by increasing their chlorophyll a: carbon ratio. Additionally, the levels of photoprotective pigments decreased from south to north, as a result of acclimation to a low-light environment and reduced exposure to ultraviolet radiation. According to ecological assumptions picophytoplankton should be favored in light- and nutrient-limited environments. However, the results did not follow that pattern, the proportion of picophytoplankton being highest in the relatively nutrient rich Baltic Proper. The study was performed during the decline of an extensive bloom of filamentous cyanobacteria, a successional phase in which picophytoplankton often dominate the phytoplankton community. The estuarine studies performed in the Bothnian Bay (Råne estuary) and in the Bothnian Sea (Öre estuary) showed different successions. In the Råne estuary no spring phytoplankton bloom occurred and highest primary production was observed during the summer. This absence of a spring bloom was explained by low phosphorus and high ADOM concentrations, while the summer maximum could be explained by higher temperature and nutrient concentrations. In the Öre estuary a marked phytoplankton spring bloom was observed as well as an ADOM sustained bacterial production phase. The later secondary peak of bacterial production observed in summer, concomitant with an extended secondary primary production peak, suggests that autochthonous dissolved organic matter supported the bacterial growth Furthermore, the photosynthetic efficiency (i.e. phytoplankton growth rates) was lower during spring, indicating that high ADOM, and thus lower light and phosphorus availability, disfavored phytoplankton growth. Our modeling study showed that climate change can impact the food web; however effects will be different between basins. In the southern Baltic Sea elevated temperature and nutrient discharge may promote nutrient recycling and oxygen consumption, potentially extending anoxic areas, sediment nutrient release and cyanobacteria blooms. In the north, increased inflow of ADOM may promote heterotrophic bacterial production and decrease primary production due to light attenuation and lower phosphorus availability. This will favor the heterotrophic microbial food web and consequently lead to lower food web efficiency of the ecosystem.

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Gutierrez, Leopoldo. "A role of humic matter and ore oxidation in rheology of oil sand slurries and in bitumen extraction." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44249.

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Eight oil sands ores were tested in order to quantify the levels of humic acids in these samples through the alkali extraction test originally developed to determine the oxidation of bituminous metallurgical coals. The test gives a concentration of humic acids released from ores, which in combination with the measurement of the total organic carbon content in the alkali extracts provides a measure of ore/bitumen weathering. It was found that poor ores exhibited the highest tendency to leach large amounts of humic acids per gram of bitumen in the samples which was quantified using the absorbance at 520 nm obtained from the UV/visible spectra. The results of contact angle measurements of water on bitumen showed that bitumen became more hydrophilic as pH increased, and that the hydrophobicity of bitumen drastically decreased when the sample was artificially oxidized. Additionally, the results suggested that humic acids make bitumen hydrophilic only if they are part of the internal/surface bitumen structure. Slurries of good ores displayed higher yield stresses than slurries of poor ores. This result is explained by the higher bitumen concentration existing in slurries of good ores which leads to more aggregation. Additionally, it was shown that bitumen oxidation/hydrophobicity also affected the rheology of oil sands slurries which also explains that slurries of poor ores displayed lower cohesion/aggregation than slurries of good ores. Yield stress data agreed with data obtained from power draw measurements that showed that good processing ores required more power for mixing. Extraction data obtained from flotation experiments indicated that the role of humic acids naturally present in the ores was basically that of a depressant of bitumen since poor ores contained the highest proportion of humic acids per gram of bitumen. Overall, it is possible to assess the processability of oil sand ores by quantifying the occurrence of humic acids in the ores, and to correlate ore processability with the rheology of oil sands slurries. Although poor ores are characterized by lower viscosities and lower power requirements during mixing, the presence of humic acids in these ores and their depressing action also contribute to lower bitumen recoveries.

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Tadini, Amanda Maria. "Gênesis de espodossolos amazônicos: um estudo sobre a estrutura e a mobilidade da matéria orgânica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25012018-165500/.

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Os solos têm um importante papel na maioria das atividades que ocorrem no planeta, dentre as quais, destaca-se a sua participação nos principais ciclos biogeoquímicos. A matéria orgânica do solo (MOS) tem um papel primordial na sustentabilidade ambiental, pois está relacionada com a ciclagem de carbono e nutrientes, sendo assim uma figura chave tanto para estudos relacionados com mudanças climáticas globais, quanto para estudos agronômicos. Um dos principais fluoróforos da MOS são as substâncias húmicas (SH), as quais são fracionadas de acordo com a sua solubilidade em ácidos húmicos (AH), ácidos fúlvicos (FA) e humina (HU). O estudo das propriedades ópticas da matéria orgânica é uma importante ferramenta para a compreensão estrutural e molecular das frações húmicas. Frente ao exposto, esse trabalho teve com objetivo estudar a gêneses de Espodossolos Amazônicos através da avaliação das características estruturais da matéria orgânica e suas propriedades de complexação com metais empregando diversas técnicas espectroscópicas. Os resultados mostraram grandes acúmulos de carbono em profundidade e que a Matéria Orgânica nesses Espodossolos Amazônico é constituída de quatro grupos: - mais recalcitrante, humificada e antiga; - lábil e jovem; - recalcitrante, pouco humificada e antiga; - humificada e jovem. Claramente o trabalho mostrou que o processo de humificação não tem relação direta com a datação do material orgânico, e que fatores como textura, presença de água e microorganismos influenciaram nos processos de formação e humificação desse material orgânico. Por fim, a fração AF do solo parece ter uma contribuição oriunda de lençóis freáticos, sua estrutura química varia pouco no perfil e possui seletividade na interação com os metais presentes nesses solos. Basicamente, o AF tem alta afinidade de complexação com Al. A fração AH, entretanto, mostrou-se menos seletiva, associando-se com vários tipos de metais, como K, Fe, Mg, Zn e Al; e sua estrutura química varia bastante no perfil do solo. Em função da diversidade de metais associados ao AH, ele deve ser o principal responsável pela fertilidade do solo. Desta forma, os resultados mostraram que as três frações húmicas estão envolvidas no processo de podzolização do solo, e que o AF tem papel predominante no transporte de Al e o AH é o responsável no transporte do Fe.
Soils play an important role in most of the activities that occur on the planet. It participation in the main biogeochemical cycles can be highlighted. Soil organic matter (SOM) plays a key role in environmental sustainability, since it is related to carbon and nutrient cycling, being essential for studies related to global climate change and agronomy. One of the major SOM fluorophore is the humic substances (HS), which is fractionated according to their solubility in humic acids (HA), fulvic acids (FA) and humin (HU). The study of the optical properties of the organic matter is an important tool for structural and molecular understanding of humic fractions. Based on that, this work aimed the study of the Amazonian Spodosols genesis through the evaluation of organic matter structural characteristics and its properties of metal complexation using different spectroscopic techniques. The main results of this research showed large carbon accumulations in depth. Furthermore, it was possible to infer how the Amazonian Spodosols organic matter is divided: - more recalcitrant, humified and old; - labile and young; - recalcitrant, little humified and old; - humified and young. The study demonstrated clearly that the humification process has no direct relationship with the organic material dating, and that factors such as texture, presence of water and microorganisms have influenced the formation and humification of that organic material. The FA fraction of the soil has a contribution from groundwater and its chemical structure varies little in depth. Additionally, FA showed selective interaction with soil metals. However, the HA fraction has been shown less selective, associate with various metal types, such as K, Fe, Mg, Zn and Al. Moreover, its chemical structure varies greatly in the soil depth. Due to the diversity of metals that the HA has affinity, it should be the main responsible of the soil fertility. After all, the results showed that all the three humic fractions are involved in the process of soil podzolization. Furthermore, the FA has a predominant role in Al transport as the HA is the responsable of Fe transport.

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Santos, Cleber Hilario dos. "Análises espectroscópicas da matéria orgânica de solos sob aplicação de águas residuárias." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-20082009-160914/.

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Em todo o mundo existe uma crescente competição pelo uso de água entre diversos setores da sociedade. O consumo de água na agricultura é grande em relação a outros tipos de uso, podendo afetar a disponibilidade deste recurso para a população urbana se este não for bem administrado. No Brasil, a agricultura consome cerca de 61% da água doce total. Entre as diferentes alternativas utilizadas pelas sociedades contemporâneas para solucionar ou minimizar este problema, visando à utilização racional e eficiente desse precioso recurso natural, o reuso de águas residuárias (efluentes) é uma opção viável econômica e ambientalmente correta. O objetivo desse trabalho foi estudar as alterações na matéria orgânica de um Argissolo Vermelho Distrófico Latossólico cultivado com capim-Bermuda Tifton 85 submetidos à adição de efluentes gerados na estação de tratamento de esgoto. As amostras utilizadas foram coletadas no município de Lins/SP em experimento já em andamento. O delineamento experimental empregado foi o de blocos completos casualizados com seis tratamentos e três repetições. Os seis tratamentos estudados foram: (1) SI - sem irrigação e sem fertilização nitrogenada mineral (FNM) - (branco); (2) E100 - irrigação com efluente e 100% (520 Kg ha-1 ano-1) da dose recomendada de FNM para o capim Tifton - 85; (3) E66 - irrigação com efluente e 66% (343,2 Kg ha-1 ano-1) da FNM; (4) E33 - irrigação com efluente e 33% (171,6 Kg ha-1 ano-1) da FNM; (5) E0 - irrigação com efluente e 0% (0 Kg ha-1 ano-1) da FNM; (6) W100 - irrigação com água de consumo e 100% (520 Kg ha-1 ano-1) da FNM. Dessas amostras foram extraídos os ácidos húmicos (AH) para observar os efeitos da adição do efluente de esgoto tratado (EET) utilizando ressonância magnética nuclear de 13C (13C RMN), infravermelho com transformada de Fourier (FTIR), fluorescência de luz uv-visível, ressonância paramagnética eletrônica (RPE) e análise elementar (C, H, N, S). Para análise do solo intacto utilizou-se a fluorescência induzida por laser e os teores de carbono foram determinados pelo carbono orgânico total (COT). Através dos resultados obtidos pela análise elementar, FTIR e 13C RMN não foi possível obter informações a respeito das alterações na composição dos AH após a adição do EET, pois estas técnicas não foram sensíveis às mudanças da MO. Tanto os experimentos de FTIR como o de 13C RMN forneceu espectros com bandas características de grupos alifáticos, comprovando seu alto grau de alifaticidade. Os resultados da espectroscopia de fluorescência em solução demonstraram que a irrigação com EET aumenta tanto a concentração de estruturas complexas quanto o grau de humificação dos AH. Os resultados de FIL para solos inteiros, entretanto, não mostraram alteração significativa com a irrigação com EET (exceto o tratamento E33), indicando que as alterações das substâncias húmicas no solo analisado ocorreram preferencialmente nos AH e afetando muito pouco da humina, que representa mais de 80% das SH do solo. Os resultados obtidos por RPE demonstraram que os tratamentos irrigados com EET apresentaram um aumento na concentração de radicais livres do tipo semiquinona, com o aumento da adubação, exceto o tratamento E33. Sendo assim, em relação a MOS, a irrigação com EET por um período de quatro não causa mudanças significativas, e neste aspecto pode ser indicada como alternativa de irrigação não impactando significativamente a matéria orgânica e proporcionando benefícios econômicos, ambientais e sociais.
Around the world there is a growing competition for the use of water among several sectors of society. Water consumption in agriculture is large when compared to other types of use and can affect the availability of water for the urban population unless it is well administered. In Brazil, agriculture consumes about 61% of the total freshwater. Among the different ways tried by contemporary societies to solve or minimize this problem, aiming to use rationally and efficiently this precious natural resource, reuse of wastewater (effluents) is an economically viable and environmentally correct option. The aim of this work was to study the changes in organic matter in a Typic Hapludults cultivated with Tifton 85 Bermudagrass submitted to addition of effluent generated by sewage treatment. The utilized samples were collected at Lins / SP, being part of a previously started experiment. The experimental design employed was the randomized complete blocks, with six treatments and three replications. The analyzed six treatments were: (1) WI - without irrigation and without nitrogen as mineral fertilizer (NMF) - (white), (2)E100 - irrigation with effluent and 100% (520 kg ha-1 year-1) of the recommended dose of NMF for the Bermudagrass Tifton - 85, (3) E66 - irrigation with eflluent and 66% (343.2 kg ha-1 year-1) of the NMF, (4)E33 - irrigation with effluent and 33% (171.6 Kg ha-1 year-1) of the NMF,(5) E0 - irrigation with effluent and 0% (0 kg ha-1 year-1) of the NMF,(6) W100 - irrigation with water for consumption and 100% (520 Kg ha-1 year-1) of the NMF. Humic acids (HA) were extracted from these samples in order to observe the effects of adding treated sewage effluent (TSE) using nuclear magnetic resonance of 13C (13C NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, UVvisible and fluorescence spectroscopy, electronic paramagnetic resonance (EPR) spectroscopy and elementary analysis (C, H, N, S). In order to analyze the whole soil, laser induced fluorescence (LIF) was utilized, and the carbon levels were determined through total organic carbon (TOC). Through the results obtained by elementary analysis, FTIR and 13C NMR, it was not possible to obtain information about changes in the composition of HA after adding the TSE, because these techniques were not sensitive to changes in OM. Both 13C NMR and FTIR provided spectra with bands typical of aliphatic groups, showing their high degree of aliphaticity. The fluorescence spectroscopy results for samples in solution demonstrated that the irrigation with TSE increases both the concentration of complex structures and the humification degree of HA. The results of LIF for the whole soil, however, showed no significant change with irrigation with TSE (except for the treatment E33), indicating that changes of humic substances in the analyzed soil occurred mainly in HA, and affecting very little on humin, which represents more than 80% of the soil HS. The results obtained by EPR demonstrated that the treatments irrigated with TSE showed an increase in the concentration of semiquinone-type free radicals, with increasing fertilization, except for the treatment E33. Therefore, regarding SOM, irrigation with TSE along a four years period did not cause significant changes, and, under this viewpoint, it can be indicated as an alternative irrigation not significantly impacting the organic matter and providing economic, environmental and social benefits.

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Check, Jason Kenneth. ""Characterization and removal of NOM from raw waters in coastal environments"." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-02162005-215318/unrestricted/check%5Fjason%5Fk%5F200505%5Fmast.pdf.

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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2005.
Michael Saunders, Committee Chair ; Paul Work, Committee Member ; Jaehong Kim, Committee Member. Includes bibliographical references.

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Narimoto, Kelly Mayumi. "\"Técnicas espectroscópicas aplicadas à análise da matéria orgânica do solo em pomares de citros sob adição de lodo de esgoto\"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-29012007-114840/.

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A produção de lodo de esgoto vem aumentando a cada dia nas estações de tratamento, e a sua disposição final é um problema a ser resolvido. Uma das alternativas encontradas para a disposição final desses resíduos com benefícios ambientais e principalmente econômicos é a reciclagem agrícola, devido a sua composição em termos de matéria orgânica e nutrientes para as plantas. O objetivo deste trabalho foi avaliar os efeitos da adição do lodo de esgoto na matéria orgânica do solo, em um experimento de curto período de duração. As amostras utilizadas neste experimento foram coletadas na Fazenda Retiro, município de Monte Azul Paulista/SP, em áreas com cultivo de citros. O experimento foi composto de 5 tratamentos, uma testemunha e 4 doses de logo de esgoto. Além dos 5 tratamentos também foram amostrados o solo de mata (referência) e lodo de esgoto. Dessas amostras foram extraídos os ácidos húmicos (AH). Foram avaliadas as alterações ocorridas nas estruturas dos AH quanto aos teores de carbono, composição de grupos funcionais, número de radicais livres do tipo semiquinona e grau de humificação. O solo in natura também foi avaliado quanto aos teores de carbono e grau de humificação da matéria orgânica (MO). Para isso, foram utilizadas técnicas como análise elementar, TOC e espectroscopia de EPR, 13C RMN, FTIR, UV-Vis, Fluorescência e FIL. Através dos resultados de análise elementar, foi possível notar que não houve alterações na estrutura dos AH após a adição de lodo de esgoto, podendo ser comprovado através dos espectros de FTIR e 13C RMN, onde não foram observadas diferenças significativas para os diferentes tratamentos. A adição de lodo de esgoto em solos sob cultivo agrícola, entretanto, incorporou MO fresca, pois quando se compara o solo testemunha e o solo que recebeu a dose mais alta de lodo observa-se um aumento de 75% no carbono orgânico do solo. O AH do lodo de esgoto possui um caráter bastante alifático e em sua estrutura uma considerável quantidade de radicais livres do tipo semiquinona. Ao ser adicionado ao solo, observa-se que modifica a concentração do número de radicais livres do tipo semiquinona sem alterar os grupos funcionais do AH do solo. Portanto, no sistema estudado, a adição de lodo de esgoto mostra que o número de radicais livres do tipo semiquinona presentes no solo não é proporcional ao grau de humificação da MO do solo. Os resultados demonstraram que a espectroscopia de fluorescência tanto em solução como a Induzida por Laser forneceu dados coerentes à cerca do grau de humificação da MO. Foi possível observar uma diminuição no grau de humificação no solos submetidos à adição de lodo de esgoto, aproximando-se do solo de mata utilizado como referência. A concentração de carbono no solo aumentou, mesmo depois de ter sido interrompida a aplicação por 2 anos, e o grau de humificação da MO diminuiu, sendo menor ainda do que o solo de mata utilizado com referência. Portanto, podemos considerar este tipo de manejo onde se utiliza lodo de esgoto para condicionamento do solo apropriado tanto do ponto de vista ambiental quanto do ponto de vista agronômico.
The production of sewage sludge increases daily in treatment stations and definitive disposal is a problem to be resolved. One of the alternatives found to dispose such residues, with environmental and economic benefits, is agricultural recycling, owing to its organic composition and plant nutrients. The objective of the present work was to asses the effects of waste sludge addition to soil organic matter in an experiment of short duration. The samples used in this experiment were collected from Fazenda Retiro, a municipality of Monte Azul Paulista/SP, in an area that has citrus plantations. The experiment was composed of 5 treatments, reference soil and 4 sewage sludge doses. In addition to the 5 treatments, the forest soil (reference) and sewage sludge were also sampled. From these samples humic acids (HA) were extracted. The alterations that occurred in the HA structures were assessed regarding ratios of carbon, composition of functional groups, number of semiquinone-type free radicals and rate of humification. In natura soil was also assessed regarding carbon ratio and rate of humification of organic material (OM). Thus, techniques as elementary analysis, TOC and EPR spectroscopy, 13C RMN, FTIR, UV-Vis, Fluorescence and FIL were used. By means of elementary analysis results, it was possible to notice that there was no alteration in the HA structure after addition of sewage sludge, therefore, verifying through FTIR and 13C RMN spectra no significant differences observed for the different treatments. However, addition of sewage sludge in agricultural cultivated soils incorporated fresh OM, since when comparing the reference soil and the soil that received the highest dose of sludge, an increase of 75% is observed in the organic carbon of the soil. The HA of the sewage sludge has a very aliphatic characteristic and in its structure, a considerable quantity of semiquinone-type free radicals. It is observed that when added to the soil, it modifies the concentration of the number of semiquinone-type free radicals, without altering the HA functional groups of the soil. Therefore, in the studied system, addition of sewage sludge demonstrates that the number of semiquinone-type free radicals found in the soil is not proportional to the rate of OM humification of the soil. The results demonstrated that fluorescence spectroscopy in solution, as well as Laser-Induced fluorescence of whole soil, provided coherent data concerning the rate of OM humification. It was possible to observe reduction in the rate of humification in soils submitted to sewage sludge, in close approximation to the forest soil used as reference. The carbon concentration in the soil increased, even after interrupting application for 2 years, and humification degree of OM diminished, proving to be less than the forest soil used as reference. Thus, we can consider this type of management, when sewage sludge is used to condition soil, as appropriate from an environmental point of view, as well as from an agronomical one.

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15

Louie, Stacey Marie. "Characterization and Modeling of Macromolecules on Nanoparticles and Their Effects on Nanoparticle Aggregation." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/396.

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The increasing production and usage of engineered nanoparticles has raised concerns about potential ecological and human exposures and the risks these novel materials may pose. Nanoparticles are often manufactured with an organic macromolecular coating, and they will attain further coatings of adsorbed natural organic matter (NOM) in the environment. The overall objective of this thesis is to improve our ability to quantify the effects of adsorbed coatings on nanoparticle fate in the environment. The physicochemical properties of the coating or the adsorbing macromolecule are expected to strongly mediate the surface interactions, and hence the environmental fate, of coated nanoparticles. To this end, this research focuses on assessing a coating characterization method and applying extensive characterization of NOM coatings to enable the development of correlations to predict nanoparticle deposition onto model environmental surfaces and aggregation. The first objective is to assess the applicability of a soft particle electrokinetic modeling approach to characterize adsorbed layer thickness, which contributes to repulsive steric forces that will affect nanoparticle deposition. A statistical analysis determined that high uncertainty in fitted layer thicknesses will limit this approach to thin, low-charged coatings (for which it may be advantageous to typical sizing methods such as dynamic light scattering). Application of this method in experimental studies further confirmed the model limitations in estimating layer thicknesses and the inability of this measurement (and other commonly measured properties) to fully explain nanoparticle deposition behavior. These results demonstrated the need for improved detail and accuracy in coating characterization. The second objective is to correlate the properties of NOM to its effects on gold nanoparticle aggregation, with particular focus on the role of heterogeneity or polydispersity of the NOM molecular weight. Multiple types of NOM collected from representative water bodies and soils were used, both in whole and separated into molecular weight (MW) fractions, and characterized for chemical composition and MW distribution. While average MW of the NOM provided good correlation with aggregation rate, the highest MW components were found to contribute disproportionately in stabilizing nanoparticles against aggregation, highlighting the importance of measuring and accounting for high MW components to explain nanoparticle aggregation. However, an outlier from the MW trend was identified, emphasizing the need for additional characterization (e.g. of reduced sulfur content or the conformation of the adsorbed NOM) to fully explain the effects of NOM on nanoparticle aggregation. Altogether, this research provides novel knowledge that will guide future application of characterization methods to predict attachment processes for coated nanoparticles in the environment.

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16

Pigatin, Lívia Botacini Favoretto. "Compostos orgânicos de origem agroindustrial e urbana aplicados à produção vegetal e fertilidade do solo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-20042011-090432/.

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A definição mais amplamente aceita estabelece que compostagem é a decomposição controlada, exotérmica e bioxidativa de materiais de origem orgânica por microorganismos autóctones, num ambiente úmido, aquecido e aeróbio, com produção de dióxido de carbono, água, minerais e uma matéria orgânica estabilizada, definida como composto. Em função do potencial inerente aos compostos orgânicos tem-se observado sua crescente utilização na agricultura, tomando lugar dos fertilizantes minerais. Devido à disponibilidade e baixo custo na região de São Carlos-SP, os compostos a serem utilizados foram provenientes de resíduos de poda de árvores, bagaço de laranja, torta de filtro e esterco bovino. A humanidade produz uma grande quantidade de tipos de resíduos, os quais podem ser utilizados como matéria-prima no processo de compostagem. A poda de árvores é um resíduo facilmente encontrado tanto na zona rural como nas cidades, sendo geralmente descartada. Nas cidades este descarte pode se tornar um problema, na medida em que aumenta o volume de lixo produzido, sobrecarregando os depósitos ou aterros sanitários. O bagaço de laranja é o principal subproduto da indústria de processamento de citrus, correspondendo a cerca de 45% da massa total da fruta e pode se tornar um grande problema para indústria, pois se deteriora muito rápido durante a estocagem. A torta de filtro é um resíduo proveniente da indústria sucroalcooleira e é obtido do processo de clarificação do caldo de cana. O esterco bovino é um resíduo amplamente usado in natura como adubo orgânico, porém, o processo de compostagem torna-o mais estável e otimiza suas propriedades fertilizantes. De maneira geral, a influência dos compostos orgânicos na produção vegetal e na fertilidade do solo requer mais estudos devido à complexidade dos agroecossistemas. O objetivo desse trabalho foi avaliar a influência de diferentes compostos orgânicos nas doses selecionadas, na produção da planta medicinal Ocimum selloi Benth em um solo tropical arenoso (Latossolo Vermelho-Amarelo distrófico, coletado na Fazenda Canchin, na região de São Carlos-SP), em comparação com fertilizante mineral. Para observar os efeitos da adubação orgânica ou mineral foram analisados os ácidos húmicos extraídos dos solos utilizando espectroscopia na região do infravermelho próximo com transformada de Fourier, fluorescência e análise elementar. Para a análise do solo intacto utilizou-se a fluorescência induzida por laser e espectrsocopia na região do infravermelho médio. Também foram realizadas análises de fertilidade do solo e do tecido vegetal, bem como analíses para avaliação do desenvolvimento vegetal. A análise estatística dos dados (Análise de Componetes Principais) de fertilidade do tecido vegetal e do solo, e dos dados de NIRS, mostraram uma separação dos tratamentos em dois grupos. Foi possível verificar que o tratamento L2 foi o mais próximo do tratamento com adubação mineral, enquanto que os tratamentos L1, L3 e L4 ficaram mais próximos ao tratamento referência (sem adubação). Esses resultados são condizentes com o diagnóstico nutricional das plantas pelo método visual, além de serem similares com as análises químicas e espectroscópicas feitas por Fialho et al. (2010). Experimentos de infravermelho com transformada de Fourier forneceram espectros com bandas características de grupos alifáticos para o ácido húmico extraído do lodo, comprovando seu alto grau de alifaticidade. Dados de fluorescência utilizando diferentes metodologias e fluorescência induzida por laser, de amostras de solo intacto, apresentaram comportamento similar. É importante salientar, que de maneira geral, o tratamento L2 (adubação com composto que possue como material de partida esterco bovino e poda de árvores) é o mais similar ao fertilizante mineral, podendo trazer maiores benefícios quando aplicados ao solo em questão. De modo geral constata-se a viabilidade do uso de compostos orgânicos como alternativa ao uso de fertilizantes minerais, contudo o manejo e as implicações na nutrição de plantas e a plena produtividade das culturas ainda representa desafio importante para as pesquisas.
The most widely accepted definition about composting is that it is a controlled exothermic and bioxidative decomposition of organic materials by autochthonous microorganisms, resulting in a wet, warm and aerobic environment, with production of carbon dioxide, water, minerals and, a stabilized organic matter, defined as compost. Due to the availability and low cost in the region of São Carlos-SP, the organic composts used came from waste of tree pruning, orange bagasse, filter cake and manure. The humanity produces a lot of kinds of residues which can be use as raw material in composting production. Pruning trees is a waste easily found in both rural and urban areas, and they are generally discarded. In the cities, this disposal may become a problem, because it increases the volume of produced waste, overloading quickly deposits or landfills. The orange peel is the main by-product of citrus industry, representing about 45% of the total weight of the fruit and it can becomes a major problem for industry, because it deteriorates very rapidly during storage. The filter cake is a residue from the ethanol industry and is obtained from the solid precipitate from the sugarcane juice clarification (to produce sugar or ethanol) and, the boiler ash. The bovine manure is a waste widely used in natura as organic fertilizer however; the composting process makes it more stable and enhances its fertilizing properties. In general, the influence of organic composts in plant production and soil fertility requires more studies due to the complexity of agroecosystems. The objective of this work was to evaluate the influence of different composts and selected doses, on the production of the medicine plant Ocimum selloi Benth in a tropical sandy soil (colleted at Canchin Farm in the region of the city of São Carlos, São Paulo state), in comparison to mineral fertilizer. The studies showed differences between composts applied in the soil. Non-additional application of mineral fertilizers was done. The results were compared with the former ones observed by Fialho et al. (2010), using chemical and spectroscopic methods to evaluate the compost humification. Analysis of fertility of the soils under organic composts application or not, analysis of fertility of plant tissues (leaves) and analysis for evaluation of plant development were done to evaluate the performance of the tested treatments (L1, L2, L3 and L4). In order to observe the effects of the composts addition, the humic acids extracted from soils were analyzed by Fourier transform infrared spectroscopy (FTIR), fluorescence spectroscopy and elementar analysis. To analyse the intact soil laser induced fluorescence (LIF) and near-infrared reflectance spectroscopy (NIRS) was used. The results obtained with Principal Component Analysis (PCA) of fertility analysis of plant tissues and soils and NIRS, showed the treatments were separated into two main clusters. It was possible to verify the treatment called L2 and were nearest to commercial treatment (mineral fertilizer) and in the L1, L3 and L4 were nearest to the reference samples. These results are consistent with the nutritional diagnosis of plants by the visual method, and are similar to the chemical and spectroscopic analysis made by Fialho et al. (2010).The results obtained by Fourier transformed infrared showed spectra with characteristic bands from aliphaticity groups for humic acid from organic composts, confirming their high aliphacitity degree. Data from fluorescence utilizing different methodologies and laser induced fluorescence, from intact soil, showed similar results. Importantly, that in general, treatment L2 is most similar to mineral fertilizer, and can bring greater benefits when applied to the soil in question. Overall it appears the feasibility of using organic composts as an alternative to the use of mineral fertilizers, but management and the implications for plant nutrition and optimum crop yield still represents an important challenge for research.

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Martelli, Lilian Fernanda de Almeida. "Avaliação quantitativa e qualitativa da matéria orgânica de solo sob a aplicação de efluente de esgoto tratado em biodigestor anaeróbio." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-19052011-105924/.

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Uma das alternativas encontradas para a reutilização de efluentes de esgotos tratados é o emprego deste material na agricultura como adubo orgânico, podendo substituir total ou parcialmente a adubação mineral. Essa prática, que se constitui de benefícios no que tange à reciclagem de nutrientes, representa uma economia de água no setor agrícola, estimada em cerca de 70% do consumo total no Brasil. Neste trabalho, pretendeu-se investigar o impacto na matéria orgânica do solo, submetido à irrigação com efluente proveniente de um biodigestor anaeróbio.
Através da realização de um experimento de campo, sob o cultivo de sorgo, realizou-se a comparação, em relação à matéria orgânica, de amostras de solo que receberam irrigação em dosagens diferenciadas do efluente tratado àquela de um solo \"testemunha\" (branco), o qual recebeu apenas irrigação com água ao longo do experimento e de um solo que recebeu anteriormente adubação convencional, segundo as recomendações do Instituto Agronômico de Campinas (IAC). Estabeleceu-se, ainda, comparações com amostras de solo coletadas na mesma propriedade. Avaliou-se a estabilidade (humificação) da matéria orgânica, como indicadora da capacidade fertilizante do efluente, quando incorporado ao solo. A qualidade do efluente do biodigestor foi acompanhada antes do início do experimento, de modo a verificar suas características principais e particularidades.
A utilização de ferramentas como a PCA e planejamento fatorial foi de grande relevância para a análise dos resultados e condução dos experimentos.
As técnicas químicas e espectroscópicas mostraram que o benefício proporcionado pela adição de efluente ao solo, mesmo em um experimento de curta duração, pode apresentar alterações, mesmo que não sejam tão pronunciadas.
Os resultados obtidos para amostras de ácidos húmicos em relação ao tamanho de partículas evidenciaram um comportamento notado em estudos bastante recentes, em relação à estrutura das substâncias húmicas.
An alternative found for treated sewage effluents reuse is to apply this material in agriculture as a fertilizer, in order to replace totally or partially the mineral fertilizers. This practice, beyond inherent benefits due to nutrients recycling promotes agricultural water reuse, which is responsible of around 70% of the total water consumption in Brazil. In this work, it was intended to investigate the soil organic matter impact, under irrigation using effluent from an anaerobic biodigester. Through a field experiment under \"sorgo\" culture, a comparison was established, related to the soil organic matter, of soil samples that had been applied different treated effluent concentrations to soil samples that received only water (\"testemunha\"- blank) or water and mineral fertilizer according to the Campinas Agronomic Institute recommendations. Other comparisons, among soil samples under citrus culture were also established. The soil organic matter humification was evaluated, as an indication of the effluent fertilizing ability when applied in soil. The biodigester effluent features were checked before the experiment beginning, in order to verify its mais features and particularities.
Tools as Principal component Analysis and factorial design were of such relevance for the results analysis and experiments execution.
The spectroscopic and chemical techniques showed that the benefits from the effluent addition in soil, even in a short-term experiment, can present changes.
The results for the humic acids samples concerning the particles size evidenced the behavior presented in recent studies, related to humic substances structures.

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18

Martins, Bruno Henrique. "Aspectos químicos e potencial de sequestro de carbono em áreas sob diferentes manejos de solo." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-24022014-111711/.

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O objetivo do presente estudo foi avaliar a dinâmica e reatividade da matéria orgânica do solo (MOS) e substâncias húmicas (SH) em duas situações distintas, no que concerne ao manejo de solo, práticas agroflorestais e condições climáticas, avaliando o potencial de sequestro de C e mitigação de efeitos do aumento do efeito estufa. O estudo foi conduzido em dois campos experimentais, sendo o primeiro, instalado em Beltsville - Maryland, Estados Unidos, sob coordenação do Departamento de Agricultura norte-americano (USDA/ARS), composto por sistemas agrícolas convencionais com manejo mínimo (PC), plantio direto sem manejo (PD) e orgânicos com plantio direto (2, 3 e 6 anos, com adição de esterco aviário). O segundo campo experimental, instalado em Itatinga - São Paulo, Brasil, compreende área de reflorestamento de floresta de eucalipto, em duas fazendas (Entre Rios - ER - e Areona - AN) com perfis de solo diferentes (Latossolo e Neossolo quartzarênico, respectivamente) com e sem adição de biossólido. Para o primeiro campo foram coletadas amostras de solo até 30 cm em 5 incrementos, sendo realizado, em seguida, o fracionamento físico da MOS, em matéria orgânica particulada livre (MOPl) e oclusa (MOPo) para análises de espectroscopia na região do infravermelho (MIR) e pirólise acoplada a GC/MS (PY-GC/MS). Para o segundo campo experimental foram coletadas amostras de solo até 20 cm, seguindo de extração de SH para análises espectroscópicas. No campo experimental americano, observou-se maior teor de C nos sistemas de plantio direto, sobretudo nos sistemas orgânicos, em comparação ao sistema convencional (cerca de 24% de aumento). Os dados obtidos através da espectroscopia de MIR mostraram maiores graus de condensação e hidrofobicidade, influindo em maior humificação e resistência à atividade microbiana para as amostras nos sistemas orgânicos. Os resultados de PY-GC/MS foram analisados por testes não paramétricos de Kruskal-Wallis e Mann-Whitney, sendo observada a maior incidência de estruturas moleculares de caráter fenólico aromático em amostras de MOPo para os sistemas orgânicos considerados, e a maior ocorrência de núcleos condensados, oriundos de lignina e outras fontes, ligados a cadeias alifáticas em amostras de MOPl para os mesmos sistemas, em relação aos demais analisados em estudo. Os resultados obtidos para o campo experimental americano ilustrou maior impacto do manejo orgânico do solo, frente aos demais considerados, no que concerne ao potencial acumulo de carbono e incidência de estruturas mais condensadas e de maior recalcitrância. Os dados do segundo campo experimental, em áreas de reflorestamento de eucalipto no estado de São Paulo, demonstraram comportamentos distintos com maior teor de C e menor grau de humificação (cerca de 25 e 30%, respectivamente) para áreas submetidas à adição de biossólido para a fazenda Areona (AN), sendo observado perfil inverso para a fazenda Entre Rios (ER) (decréscimo de cerca de 20% para C e aumento de, aproximadamente, 100% no grau de humificação). Através dos dados obtidos através de espectroscopia de infravermelho, pôde-se observar maiores índices de condensação (grau de humificação), em ambas as fazendas, nas áreas sob adição de biossólido, ao passo que somente na fazenda ER foram observados maiores índices de hidrofobicidade (resistência à degradação microbiana) nestas mesmas áreas. Assim como nos resultados obtidos as amostras de solo intacto, foi observado maior grau de humificação para amostras de AH na fazenda ER, em áreas condicionadas com biossólido, ao passo que menor grau de humificação para as mesmas áreas na fazenda AN. Assim sendo, conforme mencionado, uma das áreas de reflorestamento tratada com biossólido mostrou aumento no teor de carbono no solo (em solo arenoso) e a outra mostrou decréscimo (solo com teor mediano de argila). As análises qualitativas, como determinação do grau de humificação da matéria orgânica em amostras de solos e substâncias húmicas, foram coerentes com o aumento ou decréscimo dos teores de carbono nos dois solos, dando consistência as observações das duas situações de campo analisadas. Dessa maneira, verificou-se o maior impacto da adição da aplicação de biossólido em Latossolos em relação à área de Neossolo quartzarênico. O entendimento e avaliação da resposta da matéria orgânica e seus constituintes húmicos frente a diferentes situações é de extrema importância para obtenção de sustentabilidade ambiental, no que concerne à mitigação de efeitos inerentes às mudanças climáticas globais.
The aim of the following study was to evaluate the dynamics and reactivity of soil organic matter (SOM) and humic substances (HS) in two different situations, regarding soil tillage, forestry practices and climate conditions, considering C sequestration potential and greenhouse effects mitigation. The study was conducted in two different field experiments, being the first one a long-term field trial project installed in Beltsville, Maryland - United States, coordinated by the United States Department of Agriculture (USDA), comprising different soil tillage systems as it follows: chiesel till (CT), no till (NT) and 2, 3 and 6-year organic agriculture (with poultry manure addition). The second experimental field was installed in Itatinga, São Paulo - Brazil, comprising an eucalyptus forestry system being two farms (Entre Rios - ER, and Areona - AN), presenting different soil prolife (Oxisol and Quartzarenic Neosoil) and sewage sludge (SS) amended areas. For the first experimental field soil samples were collected to 30 cm depth in 5 increments, followed by SOM physical fractionation in occluded and free particulate organic matter (oPOM and fPOM, respectively) for mid infrared (MIR) spectroscopy and pyrolysis coupled with gas chromatography/mass spectrometry (PY-GC/MS) analysis. For the second experimental field, soil samples were collected to 20 cm depth, followed by HS extraction and spectroscopic analysis. The results for the first experimental field showed a C content increase (about 24%) for the organic systems, comparing to the others considered. Data obtained by MIR spectroscopy showed higher condensation and hydrophobicity degrees, resulting in higher humification and microbial decomposition resistance, for the organic systems samples. The results obtained by PY-GC/MS were analyzed by Kruskal-Wallis and Mann-Whitney non parametric tests and it was observed a higher incidence of phenolic and aromatic molecular structures in oPOM samples, and a higher occurrence of condensed structures, derived from lignin and other sources, bonded to aliphatic chains, in fPOM samples for the organic systems analyzed, comparing to the others systems considered. This way, the results obtained for the American experimental field showed a higher impact of organic tillage systems, regarding the soil carbon accumulation potential and the incidence of more condensed and recalcitrant structures. The results regarding the second experimental field showed an interesting behavior with C content increase and humification degree decrease in the SS amended areas (about 25 and 30%, respectively) for the Areona (AN) farm, nevertheless, being observed an inverse behavior for the Entre Rios (ER) farm samples (about 20% C content decrease and nearly 100% humification degree increase). From the infrared spectroscopy data it could be observed higher condensation degree (inferring higher humification degree) in the SS amended areas for both farms considered, however only for the ER samples it was noted a higher hydrophobicity degree (higher microbial decomposition resistance). The same way noted for the soil samples, it was observed higher humification degree for humic acids samples in the SS amended areas for the ER farm, while for the AN samples it was noted smaller humification degree for its respective SS amended area. This way, as mentioned before, one of the SS amended forestry areas showed an increase in the soil C content (in the quartzarenic neosoil) while the other one presented soil C content decrease (oxisoil, with about 20% clay content). The qualitative analysis, such as organic matter humification degree determination for soil and HS samples were coherent to the C content increase or decrease observed for both soil profiles, being consistent to the results obtained on the field experiment scenario. This way, the results for the Brazilian experimental field showed a higher impact of the sewage sludge application in the Oxisol area, comparing to the Quartzarenic Neosoil one. The understanding and evaluation about organic matter and humic constituents response regarding different field situations is extremely important to achieve environmental sustainability and climate change effects mitigation.

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19

Martins, Jéssyca Dellinhares Lopes [UNESP]. "Nutrição mineral e produtividade da cultura da batata em função da aplicação de substância húmica e adubação fosfatada." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150284.

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Dentre os nutrientes que mais limitam a produtividade da cultura da batata (Solanum tuberosum L.) está o fósforo (P). Esta cultura tem respondido à adubação fosfatada com incrementos na produtividade até altas doses, principalmente em solos com baixo teor de P disponível, que é uma característica dos solos tropicais brasileiros, os quais são naturalmente deficientes em P. A fim de melhorar a eficiência de aplicação do adubo fosfatado, é possível utilizar fertilizantes contendo substâncias húmicas (SH) ou aplicá-las diretamente no solo. No entanto, o efeito da aplicação de SH pode depender dentre outros fatores, da textura do solo, que interfere na retenção do P. Portanto, o objetivo do presente estudo foi avaliar o efeito da aplicação de SH e doses de fertilizante fosfatado sobre a nutrição, acúmulo de matéria seca (MS), crescimento radicular, absorção e exportação de nutrientes e produtividade de tubérculos da cultura da batata, em solos de diferentes texturas. Esta pesquisa foi desenvolvida através da condução de quatro experimentos, dois em casa de vegetação e dois em campo. Dois dos experimentos foram realizados em solo de textura arenosa (um de casa de vegetação e um de campo) e os dois demais em solo de textura argilosa. Em todos os experimentos, o delineamento experimental utilizado foi em blocos ao acaso, no esquema fatorial 4 x 3. Os tratamentos consistiram de quatro doses de P (10, 50, 100 e 200 mg dm-3 de P nos experimentos de casa de vegetação; 0, 100, 200 e 400 kg ha-1 de P2O5 nos de campo) e três doses da SH (0, 1,25 e 7,5 mL vaso-1 de P nos experimentos de casa de vegetação; 0, 50 e 300 L ha-1 nos de campo). A aplicação de SH afetou ligeiramente o crescimento radicular da batateira somente no solo arenoso. No solo de textura arenosa, a aplicação da SH, especialmente na dose de 50 L ha-1 (equivalente a 1,25 mL vaso-1) no sulco de plantio, aumentou a produção de matéria seca na planta, a absorção e exportação de nutrientes e melhorou o desempenho produtivo da batateira, porém, somente na ausência ou com o fornecimento de dose reduzida do adubo fosfatado. Contudo, não aumentou a eficiência da adubação fosfatada. No solo de textura argilosa, a aplicação de substância húmica aumentou a produtividade de tubérculos da classe especial, porém não interferiu na nutrição e produtividade total da cultura da batata, independentemente da dose de fertilizante fosfatado aplicado. A associação da dose mais elevada de SH e de P não teve efeito ou reduziu a produção de MS, teor e acúmulo de nutrientes e a produtividade de tubérculos da batata. Em ambos os solos, a adubação fosfatada aumentou de forma similar a absorção de nutrientes pelas plantas, exportação de nutrientes pelos tubérculos, número de tubérculos por planta, peso médio de tubérculos e a produtividade de tubérculos da barateira.
Phosphorus (P) is among the nutrients that most limits the potato crop yield (Solanum tuberosum L.). This crop has responded to phosphate fertilization with increases in productivity up to high rates, especially in soils with low available P content, which is a characteristic of the Brazilian tropical soils, which are naturally deficient in P. In order to improve the efficiency of application of the phosphate fertilizer, it is possible to use fertilizers containing humic substances (HS) or to apply them directly to the soil. However, the effect of HS application may depend, among other factors, on soil texture, which interferes with the retention of P. Therefore, the objective of this study was to evaluate the effect of the application of SH and rates of phosphorus fertilizer on nutrition, dry matter accumulation (DM), root growth, nutrient uptake and removal and yield of tubers from the potato in different textures soils. This research was developed through the conduction of four experiments, two in greenhouse and two in the field. Two of the experiments were carried out on sandy soils (one from a greenhouse and one from the field) and the other two from a clayey soil. The treatments consisted of four rates of P (10, 50, 100, and 200 mg dm-3 of P in the greenhouse experiments, and 0, 100, 200, and 400 kg ha-1 of P2O5 in the field experiments) and three rates of the HS (0, 1.25, and 7.5 mL pot-1 in the greenhouse experiments; 0, 50 and 300 L ha-1 in the field experiments). The application of HS only slightly affected the potato root growth and only when it was cultivated in the sandy soil. In sand soil, HS application, especially at the rate of 50 L ha-1 (equivalent to 1.25 mL pot-1) in planting furrow, had increased dry matter (DM) yield, nutrient uptake and removal, and improved productive performance of the potato, but only in the absence or the supply of reduced rate of the phosphate fertilizer. However, it did not increase the efficiency of phosphate fertilization. In clay soil, the HS increased tuber yield special class, but did not affect the total tuber yield and nutrition of the potato, regardless of phosphate fertilizer rate applied. The association of the highest rates of HS and P had no effect or reduced the production of DM, concentration and uptake of nutrients, and tuber yield of potato. In both soils, phosphate fertilization increased similarly the nutrient uptake by plants, nutrient removal by tubers, number of tubers per plant, mean weight of tubers, and tuber yield of potato.

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Watanabe, Cláudia. "Fate, behavior and ecotoxicology of silver nanoparticles : interactions with natural organic matter in aquatic systems." Thesis, Université de Paris (2019-....), 2020. http://www.theses.fr/2020UNIP7009.

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Lorsqu'elles sont introduites dans l'environnement, les nanoparticules manufacturées (NPs) peuvent interagir avec des molécules biotiques et abiotiques, produisant des NPs transformées, recouvertes par ces molécules, colloïdes naturels. Ces différentes formes de NP doivent être considérées comme de nouveaux matériaux, car elles ont des propriétés différentes des NPs sources libérées dans le milieu naturel. En fait, ces transformations in situ des NPs ont des impacts significatifs sur leurs effets toxicologiques, avec des risques nouveaux ou supplémentaires peu étudiés. Ce projet vise à déterminer, comprendre et prévoir l’impact des molécules naturelles sur les transformations et les effets biologiques des NPs d’Argent, largement utilisés en tant qu’agents antibactériens. Malgré l'intérêt croissant et l'utilisation de ces NPs, les connaissances recueillies sur leurs conséquences pour l'environnement sont encore rares, car la grande majorité des études ne prend pas en compte l'effet de la présence d’enrobages d’origine naturel autour de ces particules. En fait, la plupart des études ne déterminent même pas les effets de la présence de enrobages manufacturés (par opposition aux enrobages naturels) accompagnant les NPs. Généralement, les fabricants de NP ajoutent des enrobages ioniques ou polymériques pour améliorer la mobilité et la stabilité des NPs et leur impact n’est pas systématiquement étudié. Ce projet vise à surmonter les incertitudes actuelles quant à la sécurité environnementale des nanoparticules enrobées et à explorer l'impact des molécules naturelles sur leur risque environnemental. Les objectifs du projet sont les suivants: i) caractériser les NP Ag avec de enrobages manufacturés en l'absence et en présence de molécules naturelles, y compris les substances humiques (HS) et les substances polymériques extracellulaires (EPS), ii) déterminer les effets positifs et/ou néfastes des NPs ainsi transformées sur l'algue Raphidocelis subcapitata et le micro-crustacé Daphnia similis et iii) évaluer le transfert des NPs transformés dans une chaîne alimentaire modèle simplifiée: algue-micro-crustacé. Ce projet vise donc à introduire une évaluationstandardisée et améliorée de l'écotoxicologie afin d'accroître la compétitivité et la sécurité des produits nanostructurés
When introduced in environment, manufactured nanoparticles (NPs) can interact with biotic and abiotic molecules yielding a transformed NP usually coated with these molecules (natural coating). These different forms of the NPs should be considered as new materials because them distinct properties from the released NPs forms. In fact, these in situ transformations of the NPs have relevant impacts on their toxicological effects, having new or additional risks still not studied. This project aims to determine, understand and predict the impact of natural molecules in the transformations and bioeffects of Ag NPs, widely used as antibacterial agents. Despite the growing interest and use of these NPs, the gathered knowledge on their environmental consequences is still scarce, since the large majority of the studies do not consider the effect of the presence of natural coatings around the particles. In fact, most of the studies do not even determine the effects of the presence of manufactured coatings. Generally, NPs manufacturers add ionic or polymeric coatings to improve their mobility and stabilization in terms of size. Although the possible effects of these manufacturedcoatings in the NPs behavior there is not systematically studied about their impact. This project aims to overcome the current uncertainty about the environmental safety of manufactured coated NPs, and explore the impact of natural molecules on their environmental risk. The project objectives are: i) characterize the manufactured coated Ag NPs in absence and presence of natural molecules including Humic Substances (HS) and Extracellular Polymeric Substances (EPS), ii) determinate the biocompatible and bioadverse effects of the transformed NPs on the algae Raphidocelis subcapitata and the microcrustacean Daphnia similis and iii) evaluate the transfer of the transformed NPs in the food chain alga-microcrustacean. Thus, this project purposes to introduce a standardized and improved evaluation of the ecotoxicology in order to increase the competitiveness and safety of nanostructured products
Quando introduzidas no ambiente, nanopartícula (NP) podem interagir com moléculas bióticas e abióticas produzindo uma NP transformada geralmente revestida com essas moléculas (revestimento natural). Essas diferentes formas de NPs devem ser consideradas como novos materiais, pois possuem propriedades distintas dos formulários liberados dos NPs. De fato, essas transformações in situ das NPs apresentam impactos relevantes em seus efeitos toxicológicos, tendo riscos novos ou adicionais ainda não estudados. Este projeto tem como objetivo determinar, entender e prever o impacto de moléculas naturais nas transformações e efeitos biológicos dos NPs de Ag, amplamente utilizados como agentes antibacterianos. Apesar do crescente interesse e uso desses NPs, o conhecimento acumulado sobre suas conseqüências ambientais ainda é escasso, uma vez que a grande maioria dos estudos não considera o efeito da presença de revestimentos naturais ao redor das partículas. De fato, a maioria dos estudos nem sequer determina os efeitos da presença de revestimentos fabricados. Geralmente, os fabricantes de NPs adicionam revestimentos iônicos ou poliméricos para melhorar sua mobilidade e estabilização em termos de tamanho. Embora os possíveis efeitos desses revestimentos fabricados no comportamento dos NPs não sejam sistematicamente estudados sobre seu impacto. Este projeto visa superar a atual incerteza sobre a segurança ambiental de NPs revestidos fabricados e explorar o impacto de moléculas naturais em seus riscos ambientais. Os objetivos do projeto são: i) caracterizar os NPs de Ag revestidos fabricados na ausência e presença de moléculas naturais, incluindo Substâncias Húmicas (HS) e Substâncias Poliméricas Extracelulares (EPS), ii) determinar os efeitos biocompatíveis e bioadversos dos NPs transformados nas algas Raphidocelis subcapitata e o microcrustáceo Daphnia similis e iii) avaliar a transferência dos NPs transformados na cadeia alimentar de microcrustáceos algas. Assim, este projeto tem como objetivo introduzir uma avaliação padronizada e aprimorada da ecotoxicologia, a fim de aumentar a competitividade e a segurança dos produtos nanoestruturados

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Martins, Bruno Henrique. "Estudos espectroscópicos de matéria orgânica e ácidos húmicos de solos sob adição de efluente de esgoto tratado." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-12112009-110044/.

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A crescente demanda de água nas cidades tem feito o homem buscar diferentes fontes de irrigação de culturas na agricultura, em se tratando de uma atividade que requer um grande montante de água. Neste contexto, o uso de efluente de esgoto tratado (EET), industrial ou doméstico, substituindo a água utilizada na irrigação de várias culturas, tem se mostrado ser uma medida promissora para preservá-la para o consumo humano.O propósito deste trabalho foi avaliar através de técnicas espectroscópicas (Infravermelho com Transformada de Fourier - FTIR, Espectroscopia de Fluorescência, Espectroscopia de Absorção de UV-Visível, Ressonância Paramagnética Eletrônica - RPE), as mudanças na matéria orgânica do solo (MOS) e ácidos húmicos (AH) extraídos de solo irrigado ou não com efluente de esgoto tratado, nas seguintes condições de irrigação: SI (sem irrigação com EET), 100 (irrigação com EET e umidade de solo na capacidade de campo) e 200 (irrigação com EET e umidade de solo 100% acima da capacidade de solo). Além dessas técnicas foi determinada a porcentagem de carbono e utilizada a espectroscopia de Fluorescência Induzida por Laser (FIL) para medir o grau de humificação de amostras de solo intacto, irrigados ou não com EET. As amostras de solo, sob cultura de cana-de-açúcar, foram coletadas em campo experimental situado em Lins-SP, em diferentes profundidades até 100 cm. As análises das amostras de solo demonstraram um decréscimo de porcentagem de carbono na faixa de 2 a 15% para as condições de irrigação com EET. O resultado é preocupante considerando tratar-se de solos com menos de 1% de conteúdo de carbono, e que tem com a aplicação do EET uma diminuição adicional na MOS, o que pode ser altamente limitante para a fertilidade e estrutura do solo. Os resultados obtidos por FIL para as mesmas amostras mostraram um aumento no grau de humificação variando de 9 a 30% nas áreas irrigadas com EET em relação às áreas não irrigadas com EET. Esse aumento do grau de humificação MOS é consistente com a diminuição de carbono do solo que mais provavelmente perde frações mais lábeis, permanecendo as mais recalcitrantes. Os espectros obtidos pela espectroscopia de FTIR para os AH analisados foram típicos, não mostrando diferença significativa, considerando as diferentes camadas de profundidade e irrigação ou não com EET. Os resultados obtidos por espectroscopia de fluorescência, usando três diferentes metodologias, de AH em solução mostraram, assim como a espectroscopia de FIL para amostras de solo, aumento no grau de humificação conforme aplicação de EET Assim como no caso da MOS, tal aumento no grau de humificação pode ser atribuído à degradação de frações de carbono mais lábeis e permanência das mais recalcitrantes dos ácidos húmicos analisados. Os resultados de razão E4/E6 (razão entre as intensidades de absorbância em 465 e 665 nm) para os AH analisados obtidos através da espectroscopia de absorção de UV-Visível denotaram decréscimo em seus valores nas camadas superficiais, comparando-se as três condições analisadas. Os resultados obtidos pela espectroscopia de RPE mostraram um aumento na concentração de RLS (radicais livres semiquinona) nos AH nas duas condições de irrigação, 100 e 200, sendo mais pronunciado na segunda. Corroborando com os resultados obtidos através das demais espectroscopias utilizadas, tal aumento da concentração de RLS provavelmente é oriundo de aumento de grau de humificação. Dessa forma, de acordo com os dados obtidos, o emprego de ET como fonte de irrigação em substituição à água, nas condições de solo analisadas são preocupantes, pois pode trazer limitações para a fertilidade e estrutura do solo, conforme evidenciado pelo decréscimo no conteúdo de MOS.Contudo, os experimentos devem ser continuados para confirmar e validar as tendências iniciais detectadas, bem como para buscar as alternativas de manejo dos solos e culturas para viabilizar a aplicação do EET em condições que sejam sustentáveis.
The increasing demand of water sources in the cities has done the man search for other different sources for irrigation of cultures in agricultural fields, hence it\'s an activity that demands a large amount of water. In this context, the use of treated sewage effluent (TSE), industrial or domestic, instead of water for irrigation of several cultures, has been shown to be a very promising way to save water for human consume.The purpose of this study is to evaluate by spectroscopic techniques (Fourier Transformed Infra-Red - FTIR, Fluorescence Spectroscopy, UV-Visible Spectroscopy and Electron Paramagnetic Resonance - EPR) the changes in the soil organic matter (SOM) and humic acids (HA) extracted from soils irrigated or not with treated sewage effluent, in the following concentrations of irrigation: SI (soil non-irrigated with TSE), 100 (soil irrigated with TSE and soil humidity in the same level of field capacity) and 200 (soil irrigated with TSE and soil humidity 100 % above field capacity). Besides these techniques, it was also determined the carbon percentage and used the Laser-Induced Fluorescence (LIF) spectroscopy to measure the degree of humification in samples of whole soil, irrigated or not with TSE. The soil samples analyzed in this study were collected from an experimental field in the city of Lins - SP, from a sugarcane culture soil, in the depth till 100 cm. The analysis of samples of whole soil showed a decrease in the carbon percentage in the range of 2 to 15% in the irrigation conditions comparing with the non - irrigated area. These results are preoccupying considering that it\'s a soil with less of 1% of carbon content, and has an additional decrease in the SOM when irrigated with TSE, what may cause limiting in the soil fertility and structure. The results obtained by LIF for the same samples, showed an increase in the humification degree varying from 9 to 30% in the irrigated area. This increase in the humification degree of soil organic matter (SOM) is consistent with carbon percentage decreasing in soil, which probably loses more labile fractions, remaining the most recalcitrant ones. The spectra obtained by the FTIR spectroscopy for HA analyzed were typical, not showing a significative difference, considering different layers of depth and treatment or not with TSE. The data obtained by fluorescence spectroscopy, using three different methodologies, of HA in solution showed, as well as the LIF spectroscopy for whole soils, an increment in the humification degree according to application of TSE. At the same way that happens with SOM, this increase in the humification degree may be attributed to degradation of carbon more labile fractions and remaining of the most recalcitrant ones in the humic acids. The results of E4/E6 ratio (ratio between the absorbance intensities at 465 and 665 nm) obtained by UV-Visible spectroscopy showed a decrease in the superficial layers, comparing the three conditions analyzed. The results obtained by the EPR spectroscopy showed an increase in the concentration of SFR (semiquinone free-radicals) in the HA with the increase of depth in the two conditions of irrigation, 100 and 200, being more pronunciated in the second treatment. Corroborating with the results obtained by the others spectroscopies, this increase in the SFR concentration probably may be attributed to the increase in the humification degree. In this manner, according with the obtained data, the use of TSE as source of irrigation replacing the water in the soil condition analyzed are preoccupying, hence it may cause limitations in soil fertility and structure, as evidenced by the decrease of the SOM content. However, the experiments must continue to confirm and validate the initials tendencies detected, and to search new alternatives for soil and culture tillage to make possible the TSE application in sustainable conditions.

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Bassan, Cássia Fernanda Domingues [UNESP]. "Interações de alguns ácidos orgânicos com minerais e um latossolo vermelho." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/101792.

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Universidade Estadual Paulista (UNESP)
Certain cultures present especification in the assimilation of some ions, that are or not in available ways in the soil. The minerals have fundamental paper in the presence of those elements that, a lot of times, they are together originating from of the processes of meteorization of the rocks with the decomposition of the organic matter. This work had for objective to study the extraction and/or solubilization of some present chemical elements in the studied minerals and in a red latosoil, for the action of some organic acids produced starting from the decomposition of the matter ligno-cellulousic, through the microbial action, hoping to contribute in some way in the understanding of the mechanisms of fertility of the soil and, consequently, in the mineral nutrition of plants. The used minerals were: manganite [MnO(OH)], hematite (Fe2O3), pirolusite (MnO2), caolinite [Al2Si2O5(OH)4], goethite (HFeO2), bentonite [Na3(Al,Mg)2 2(Si4O10)(OH)2.H2O] e magnetite(Fe3O4), that commonly happen in areas humid intertropicals and a red latosoil, of sandy texture that, it represents more that 20% of the area of the State of Saint Paulo. The minerals and LV were triturated and drizzled in 0,05mm mesh, separately. After having examined with relationship your structure for Difratometric of Ray-X (XRD), 1g of those minerals and LV were conditioned, separately, in glass flasks. Some samples were only treated with distilled water and other with solution 0,02 mol.L-1 of the following acids: acetic, butyric, citric, carbolic, lactic, malic, oxalic, propionic and tannic, separately, for 53 days, with weekly agitations and conditions aerobics. After the digestion of the samples, they were certain the litio concentrations, sodium, potassium, magnesium, calcium, barium, vanadium, cromium, molibdenium, manganese, iron, cobalt, nickel, copper, zinc, cadmium, mercury, boron, aluminum, silicio, tin, lead, match... (Complete abstract click electronic access below)

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Měřínská, Zuzana. "Odstranění vybraných složek z vodního prostředí koagulací." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233334.

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This thesis deals with coagulation treatment of surface water with content of humic matters, drug residues and turbidity. Commonly used coagulants (ferrous and aluminous sulphate) and natural biopolymer based on chitosan that not yet used in the Czech Republic had been studied. The aim of this work was to found the optimal application of chitosan in water treatment and comparison of its coagulation efficiency with standard inorganic coagulants. Theoretical part of the thesis contains occurrence, classification, composition, properties and importance of humic matters and drug residues and furthermore properties of chitosan and its using in water treatment. Experimental part summarizes the obtained results from the laboratory coagulation tests with inorganic coagulants and with chitosan leading to determination of its optimal dose. Other coagulation experiments were focused on finding the possibilities of combine the two coagulants (ferrous sulphate and chitosan) and to find their optimum doses and suitable ratio. The influence of pH on water treatment with using coagulation was also studied.

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Tadini, Amanda Maria. "Gêneses de espodossolos amazônico : um estudo sobre a estrutura e a mobilidade da matéria orgânica." Thesis, Toulon, 2017. http://www.theses.fr/2017TOUL0023.

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Les sols jouent un rôle important dans la plupart des activités qui se produisent sur terre, parmi lesquelles sa participation dans les grands cycles biogéochimiques n'est pas des moindres. En effet, la matière organique des sols (MOS) joue un rôle clé dans la durabilité environnementale, car elle est liée au cycle du carbone et des nutriments et ceci est un élément primordial pour les études liées au changement climatique mondial et pour les études agronomiques. L'un des principaux constituants de la MOS sont les substances humiques (AH), acides fulviques (AF) et humine (HU). L'étude des propriétés optiques de la matière organique est un outil important pour la compréhension structurale et moléculaire des fractions humiques. Ce travail porte sur la genèse de Spodosols Amazoniens par l'évaluation des caractéristiques structurelles de leur matière organique et de leurs propriétés de complexation métallique en utilisant diverses techniques spectroscopiques. Les résultats ont montré de grandes accumulations de carbone en profondeur et que la matière organique dans ces spodosols amazoniens est constituée en quatre groupes : -plus récalcitrant, humifié et ancien ; -labile et jeune ; -récalcitrant, peu humifié et ancien ; humifié et jeune. De toute évidence, le travail a montré que le processus d'humification n'a aucune relation directe avec la datation de la matière organique et que les facteurs tels que la texture, la présence d'eau et les micro-organismes ont influencé les processus de formation et d'humification de cette matière organique. Enfin, la fraction des AF du sol semble avoir une contribution provenant des eaux souterraines, sa structure chimique variant peu au sein d'un profil et ayant une interaction sélective avec métaux présents dans ces sols. La fraction des AH, cependant, s'est révélée moins sélective, associé divers types de métaux, tels que K, Fe, Mg, Zn et Al. Par contre, la structure chimique des AH semble dépendre du profil de sol. En raison de la diversité des métaux que les AH peuvent complexer, ils devraient être les principaux responsables de la fertilité du sol. Les résultats ont montré que les trois fractions humiques (AF, AH et HU) sont fortement impliquées dans le processus de podzolisation des sols et que les AF ont un rôle prédominant dans le transport d'Al tandis que les AH sont les protagonistes du transport du Fe
Soils play an important role in the most of the activities that occur on the planet. It participation in the main biogeochemical cyles can be highlighted. Soil organic matter (SOM) plays a key role in environmental sustainability, since it is related tocabon and nutrient cycling, being essential for studies related to global climate change and agronomy. One of the major SOM fluorophore is the humic substances (HS), which is fractionated according to their solubility in humic acids (HA), fulvic acids (FA) and humin (HU). The study of the optical properties of the organic matter is an important tool for structural and molecular understanding of humic fractions. Based on that, this work aimed the study of the Amazonian Spodosols genesis through the evaluation of organic matter structural characteristics and its properties of metal complexation using different spoectroscopic techniques. The main results of this research showed large carbon accumulations in depth. Futhermore, is was possible to infer how the Amazonian Spodosols organic matter is divided : - more recalcitrant, humified and old ; -labile and young ; -recalcitrant, little humified and old ; -humified and young. The study demonstrated clearly tha the humification process has no direct relationship with the organic material dating, and that factors such as texture, presence of water and micro-organisms have influenced the formation and humification of that organic material. The FA fraction of the soil has a contribution from groundwater and its chemical structure varies little in depth. Additionaly, FA showed selective interaction with soil metals. However, the HA fraction has been shown less selective, associate with various meta types , such as K, Fe, Mg, Zn and Al. Moreover, its chemical structure varies greatly in the soil depth. Due to the diversity of metals that the HA has affinity, it should be the main responsible of the soil fertility. After all, the results showed that all the three humic fractions are involved in the process of soil podzolization. Furthermore, the FA has a predominant role in Al transport as the HA is the protagonist of Fe transport

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Nováková, Šárka. "Stabilita půdní organické hmoty a huminových látek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376835.

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This diploma thesis is focused on changes of stability in organic matter by extraction in different agents. Two soils of a different type and isolated humic acids were used for stability determination. Extraction agents were selected usually used for soil metal extraction, and a changes in the structure of the organic matter was observed. Samples were characterized using FTIR analysis and elemental analysis, the extracts were measured by UV-VIS spectroscopy, absorption ratios E2/E3, E4/E6 were discovered, dynamic light scattering were determined for particle size distributions. Next part of the thesis was the assessment of the change of thermal stability using thermogravimetric analysis and differential scanning calorimetry, degradation temperatures of the extracted samples were discovered and compared with the original samples.

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Jelena, Tričković. "Primena sorpcionih parametara odabranih hidrofobnih organskih polutanata na organskoj materiji sedimenata za procenu njihove dostupnosti u sistemima sediment-voda." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2009. https://www.cris.uns.ac.rs/record.jsf?recordId=16659&source=NDLTD&language=en.

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Prirodna organska materija zemljišta/sedimenata predstavlja glavnu oblastza sorpciju hidrofobnih organskih jedinjenja, a njene osobine utiču na stepenretencije i konsekventnu (bio)dostupnost organskih jedinjenja. Da bi se procenioekotoksikološki rizik zagađenih zemljišta/sedimenata po okolinu, dizajniralaodgovarajuća strategija remedijacije ili predvidela sudbina i transport organskihpolutanata u zagađenim zonama, neophodno je razumevanje mehanizma sorpcije idesorpcije na nivou mehanizma uspostavljenih veza. U radu je izvršeno ispitivanjesorpcije i desorpcije odabranih hidrofobnih organskih polutanata, pentahlorbenzenai lindana, na sekvencijalno ekstrahovanim huminskim kiselinama i huminima izjednog uzorka sedimenta u cilju pronalaženja veze između strukturnihkarakteristika izolovanih huminskih kiselina i humina i sorpcionih i desorpcionihparametara. Afinitet za sorpciju, nelinearnost izotermi i prividna sorpciono-desorpciona histereza korelirani su sa osobinama sorbenata dobijenim izelementarne i FTIR spektroskopske analize. Predloženo je da je mehanizamsorpcije na huminskim kiselinama rezultat odigravanja raspodele i specifičneadsorpcije, pri čemu se pri nižim koncentracijama pentahlorbenzena i lindana prvopopune sorpciona mesta u kondenzovanoj aromatičnoj oblasti, a tek potom privišim koncentracijama sorpciona mesta u amorfnim alifatičnim oblastima.Sveukupno viši koeficijenti nelinearnosti dobijeni za sorpciju pentahlorbenzena na huminskim kiselinama u odnosu na nelinearnost sorpcionih izotermi lindana, ukazuju na to da u ukupnoj sorpciji pentahlorbenzena veći značaj ima mehanizam raspodele i smeštanje molekula pentahlorbenzena u hidrofobne šupljine huminskih kiselina, u odnosu na specifičnu adsorpciju. Ovi zaključci su potvrđeni rezultatima spektroskopskih istraživanja interakcija odabranih organskih jedinjenja i N-metilformamida. Predloženi mehanizam sorpcije ne može objasniti sorpciju pentahlorbenzena i lindana na uzorcima humina, većje pretpostavljeno da nelinearna sorpcija za uzorke humina može biti rezultat ostvarivanja površinskih interakcija, a visoki afinitet za sorpciju rezultat je raspodele organskih jedinjenja u amorfnim alifatičnim oblastima koje pružaju odlično okruženje za sorpciju.U cilju daljeg proučavanja mehanizma sorpcije, izvršeno je ispitivanje kinetikedesorpcije tri odabrana hidrofobna organskajedinjenja, pentahlorbenzena, lindana ipentahloranilina, posredstvom čvrstog adsorbenta, XAD-4 makroporoznejonoizmenjivačke smole. Na osnovu rezultata dobijenih za uzorak sedimenta ifrakciju < 125 µm za dva ravnotežna vremena (15 i 90 dana) i za sva odabranaorganska jedinjenja može se zaključiti da se za procenu potencijalne (bio)dostupnefrakcije organskih jedinjenja može koristiti jednostavna desorpcija u prisustvuXAD-4 makroporozne jonoizmenjivačke smole i to na dva načina: (1) ekstrakcijomsedimenta tokom 24 časa, kada frakcija koja se desorbuje odgovara frakcijijedinjenja koja se nalazi u brzo-desorbujućem domenu organske materije, ili (2)ekstrakcijom tokom 6 časova, kada frakcija koja se desorbuje odgovara polovinione frakcije jedinjenja koja se nalazi u brzo-desorbujućem domenu organskematerije.
Natural organic matter of soil/sediment make the main region for sorption of hydrophobic organic compounds, ant its properties influence the degree of retention and, consequently, (bio)availability of organic compounds. In order to assess the ecotoxicological risks of contaminated soils/sediments to the environment and design the appropriate remediation strategy or predict the fate and transport of organic pollutants in contaminated zones, it is necessary to understand the mechanisms of sorption/desorption at the level of the mechanism of established bonds. Study of the sorption and desorption of selected hydrophobic organic pollutants, pentachlorobenzene and lindane, on sequentially extracted humic acids and humins from a single sediment sample with the aim of finding the relationship between the structural characteristics of the isolated humic acids and humin and sorption and desorption parameters. Sorption affinity, nonlinearity of isotherms, and apparent sorption-desorption hysteresis were correlated to the sorbent characteristics obtained from elemental analysis and FTIR spectroscopic data. The proposed sorption mechanism on humic acids assumes that at low concentrations of pentachlorobenzene and lindane the sorption sites in the condensed aromatic region are occupied first, and then, at their higher concentrations, the sorption sites in the amorphous and aliphatic regions. Generally higher nonlinearity coefficient obtained for the sorption of pentachlorobenzene on umic acids compared with the nonlinearity of sorption isotherms for lindane, indicate that in the overall sorption of pentachlorobenzene of higher significance is the echanism of distribution and insertion of pentachlorobenzene molecule into hydrophobic dips of humic acids, compared to specific adsorption. These conclusions were confirmed with the results of spectroscopic investigation of intermolecular interaction of chosen organic compounds and N-methylformamide.Since suggested sorption mechanism could not explain sorption of pentachlorobenzene and lindane onto humin samples, it is supposed that the nonlinearity can be a result of surface interactions, while the high sorption affinity is result of distribution of organic compounds in the amorphous aliphatic regions that offer an excellent environment for sorption.With the aim of further insight into the sorption mechanism, investigation of desorption kinetics of three chosen hydrophobic organic compounds, pentachlorobenzene, lindane and pentachloroaniline, in the presence of soild adsorbent XAD-4 macroporous ion-exchange resin was performed. On the basis of the results obtained for sediment sample and fraction < 125 µm at two equilibrium times (15 and 90 days) and for all selected organic compounds, it can be concluded that the assessment of the potential (bio)avialable fraction of organic compounds may be obtained by using simple method of desorption in the presence of XAD-4 macroporous ion-exchange resin, performed in two ways: (1) by sediment extraction during 24 hours, when the desorbing fraction corresponds to the fraction of he compound that is found in the fast-desorbing domain of organic matter, or (2) by 6-hour extraction, when the desorbing fraction corresponds to one half of the fraction appearing in the fast-desorbing domain of the organic matter.

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Bassan, Cássia Fernanda Domingues 1964. "Interações de alguns ácidos orgânicos com minerais e um latossolo vermelho /." Botucatu : [s.n.], 2004. http://hdl.handle.net/11449/101792.

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Abstract: Certain cultures present especification in the assimilation of some ions, that are or not in available ways in the soil. The minerals have fundamental paper in the presence of those elements that, a lot of times, they are together originating from of the processes of meteorization of the rocks with the decomposition of the organic matter. This work had for objective to study the extraction and/or solubilization of some present chemical elements in the studied minerals and in a red latosoil, for the action of some organic acids produced starting from the decomposition of the matter ligno-cellulousic, through the microbial action, hoping to contribute in some way in the understanding of the mechanisms of fertility of the soil and, consequently, in the mineral nutrition of plants. The used minerals were: manganite [MnO(OH)], hematite (Fe2O3), pirolusite (MnO2), caolinite [Al2Si2O5(OH)4], goethite (HFeO2), bentonite [Na3(Al,Mg)2 2(Si4O10)(OH)2.H2O] e magnetite(Fe3O4), that commonly happen in areas humid intertropicals and a red latosoil, of sandy texture that, it represents more that 20% of the area of the State of Saint Paulo. The minerals and LV were triturated and drizzled in 0,05mm mesh, separately. After having examined with relationship your structure for Difratometric of Ray-X (XRD), 1g of those minerals and LV were conditioned, separately, in glass flasks. Some samples were only treated with distilled water and other with solution 0,02 mol.L-1 of the following acids: acetic, butyric, citric, carbolic, lactic, malic, oxalic, propionic and tannic, separately, for 53 days, with weekly agitations and conditions aerobics. After the digestion of the samples, they were certain the litio concentrations, sodium, potassium, magnesium, calcium, barium, vanadium, cromium, molibdenium, manganese, iron, cobalt, nickel, copper, zinc, cadmium, mercury, boron, aluminum, silicio, tin, lead, match... (Complete abstract click electronic access below)
Orientador: Ademércio Antonio Paccola
Coorientador: Pedro de Magalhães Padilha
Banca: Silas Macedo Silva
Banca: Paulo Sergio R. de Oliveira
Banca: Antonio Francisco Godinho
Banca: Rosana Cavalcante dos Santos
Doutor

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Santos, Cleber Hilario dos. "Estudo da matéria orgânica e composição elementar de solos arenosos de regiões próximas a São Gabriel da Cachoeira no Amazonas." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-04072014-105024/.

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A Amazônia representa a maior biodiversidade do mundo e representa um reservatório enorme e dinâmico de carbono, não só na biomassa, mas também no solo. O ciclo do carbono neste bioma é muito importante, principalmente para questões abordadas às mudanças climáticas. Avaliar e compreender a dinâmica do carbono e outros elementos no solo da Amazônia pode ajudar os cientistas a melhorar os modelos e antecipar cenários. Novos métodos, que permitem medições de carbono do solo in situ, são uma abordagem fundamental para este tipo de região, devido aos custos financeiros para a coleta e envio de amostras de solo da floresta para o laboratório, e demanda muito tempo nesta atividade. No presente estudo, uma topossequência de um sistema Latossolo-Espodossolo com caulim associado, desenvolvido a partir de rochas granito gnáissicas do embasamento cristalino, foi estudada. As amostras foram coletadas em São Gabriel da Cachoeira, estado do Amazonas. Dois perfis de solo: Espodossolo Humilúvico (P1) no topo e Latossolo Amarelo (P2) na meia encosta da topossequência foram descritos e amostrados em um total de dezoito amostras. Os objetivos principais foram avaliar e caracterizar através de métodos químicos e espectroscópicos a matéria orgânica e a composição elementar nestes solos arenosos utilizando a análise elementar (CHNS), espectroscopia de emissão ótica com plasma induzido por laser (LIBS), espectrometria de emissão ótica com plasma acoplado indutivamente (ICP OES), espectroscopia de fluorescência induzida por laser (FIL), fluorescência de luz UVVisível e absorção de radiação na região no UV-Visível. Através dos resultados obtidos pela análise elementar foi possível notar que para o Espodossolo Humilúvico houve variações diferenciadas nos teores de carbono, mas para o Latossolo Amarelo, não se pode inferir uma tendência de incremento ou decréscimo do teor de carbono ao longo do perfil, pois o teor de carbono para a maioria das amostras de solo foi inferior a 0,3%, o limite de detecção do CHNS. A espectroscopia de matrizes de fluorescência de excitação-emissão (MEE) foi uma técnica mais seletiva e sensível do que a fluorescência bidimensional para os ácidos húmicos (AH), mostrando informações interessantes, variações estruturais e grande diferença entre os cromóforos que emitem fluorescência nos extratos de ácido fúlvico 2 (EAF2) e AH. A combinação dos espectros de MEE com a análise de fatores paralelos (PARAFAC) permitiu caracterizar qualitativamente os EAF2, podendo identificar e associar com mais clareza os três fluoróforos obtidos, com seus respectivos componentes, ácidos fúlvicos (grupos de fluoróforos simples e complexos) e proteína, com diagnóstico de consistência do tensor núcleo (CORCONDIA) de 85,8%. Esta combinação permitiu caracterizar quantitativamente os AH, identificando a contribuição das intensidades de dois fluoróforos, associados aos AH, grupos de fluoróforos mais complexos e simples, com CORCONDIA de 84,2%. A partir dos resultados de LIBS, uma forte correlação foi encontrada e os coeficientes de correlação de Pearson\'s obtidos para o ajuste logarítmico foi de R = 0,98 e R = 0,99 para o carbono e o alumínio, respectivamente, entre os valores obtidos por LIBS e as técnicas de referências (CHNS e ICP OES) para o Espodossolo Humilúvico. Nenhuma relação foi observada para o ferro, provavelmente devido aos teores estarem abaixo do limite de detecção. A técnica FIL mostrou para o Espodossolo Humilúvico que o horizonte de transição (Tr) estaria funcionando como uma \"peneira molecular\", acumulando a matéria orgânica pouco humificada, permitindo a passagem para os horizontes de caulim (K1 e K2) de compostos com estruturas mais humificadas, mais complexas, de difícil degradação (mais recalcitrantes), mas de menor tamanho molecular, como anéis aromáticos condensados e/ou conjugação de anéis aromáticos simples, corroborando com a eficiência da extração do AH. Para o Latossolo Amarelo, observou-se um aumento no grau de humificação do horizonte superficial BA em relação ao A2. Logo, estes resultados contribuem para um melhor entendimento sobre a quantificação de carbono, grau de humificação e alterações estruturais da matéria orgânica dos solos arenosos da região de São Gabriel da Cachoeira na Amazônia.
The Amazon represents the world\'s biggest biodiversity, comprehending a large and dynamic carbon pool, considering its biomass and soil, as well. The carbon cycle in this biome is very important, especially in questions regarding climatic changes. To evaluate and to understand the carbon and other elements cycles in Amazonian soil can help scientists to improve models and foresee scenarios. New methods, allowing carbon measurements on site, are a crucial approach for this kind of region, due to the financial costs to collect and ship soil samples from forest to laboratory, and the time spent in this activity. In the present study, it was analyzed a topsequence of an Oxisol-Spodosol system with kaolin associated, generated from granitic-gneiss rocks of crystalline basement. The soil samples were collected in São Gabriel da Cachoeira, Amazonas state, Brazil, considering two different soil profiles: Spodosols (P1), at the top layer, and yellow Oxisols (P2) at the topsequence hillside, representing a total of eighteen samples. The main purpose of this study was to evaluate and characterize the organic matter content and elemental composition by chemical and spectroscopic methods using elemental analysis (CHNS), laserinduced breakdown spectroscopy (LIBS), inductively coupled plasma optical emission spectrometry (ICP OES), laser-induced fluorescence spectroscopy (LIFS), fluorescence spectroscopy and UV-Visible spectroscopy. The CHNS results showed differences in the carbon content for the Spodosol (P1) samples; however, it was not observed any differences for the Oxisol (P2) samples, once the carbon content data obtained for these samples were lower than the equipment detection limit (0.3%). The excitation-emission matrix (EEM) fluorescence spectroscopy was more sensitive for detecting humic acids (HA) than the two-dimensional fluorescence spectroscopy, showing interesting information, structural variations and large difference among chromophores that emit fluorescence in fulvic acid extracts 2 (EAF2) and HA. The EAF2 were qualitatively characterized by combining the EEM spectra with parallel factor analysis (PARAFAC), which allowed to identify clearly the three fluorophores obtained and their respective components, fulvic acids (simple and complex groups of fluorophores) and protein, with core consistency diagnostic (CORCONDIA) of 85.8%. These data also allowed to quantify the HA, identifying contributions of intensities from two fluorophores associated with HA, complex groups and simple fluorophores, presenting CORCONDIA of 84.2%. Regarding the carbon and aluminum content results for the Spodosol samples, a strong correlation was found between the LIBS values and the standard techniques (CHNS and ICP OES). The Pearson\'s coefficients obtained by logarithmic fit were R = 0.98 and R = 0.99 for carbon and aluminum, respectively. It was not observed any differences for the iron contents from the analyzed samples, probably due to the low content observed regarding the detection limit this element presents. The LIFS technique indicated that the transition horizon (Tr) would be acting as a \"molecular sieve\" in the Spodosol soil (P1), accumulating less humified organic matter, and allowing passage to kaolin horizons (K1 and K2) of compounds with more humified, more complex, difficult to degrade (recalcitrant) structures, but with lower molecular size, such as condensed aromatic rings and/or combination of simple aromatic rings. These results were in accordance to the HA extraction efficiency. For the yellow Oxisol (P2) samples, it was observed a humification degree increase in the surface horizon BA compared to the A2 horizon. This way, the data obtained contribute to a better understanding regarding carbon quantification, humification degree and organic matter structural alterations on sandy soils in São Gabriel da Cachoeira, at the Amazonian region.

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Marcelo, Adolfo Valente [UNESP]. "Decomposição de resíduos vegetais de culturas de entressafra em sistema de semeadura direta e efeitos nos atributos químicos de um Latossolo e na produtividade de soja e milho." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/105201.

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Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-27Bitstream added on 2014-06-13T20:05:52Z : No. of bitstreams: 1 marcelo_av_dr_jabo.pdf: 1194015 bytes, checksum: 68c9171ad52d863ef75fe8bb9b03c925 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Em sistema de semeadura direta, os resíduos das culturas de entressafra são utilizados para protegerem a superfície do solo dos agentes erosivos e promoverem a ciclagem de nutrientes. O objetivo desse trabalho foi avaliar o efeito de sequências de culturas na quantidade, qualidade, decomposição e liberação de nutrientes dos resíduos vegetais de culturas de entressafra, bem como a cobertura do solo proporcionada pelos resíduos, na fertilidade do solo, nas frações particulada e associada aos minerais de C, nas substâncias húmicas do solo e na produtividade de milho e soja cultivados no verão, em região de clima tropical. O experimento foi conduzido em Jaboticabal, SP (48°15’22’’ W e 21°18’58’’ S), em um Latossolo Vermelho eutrófico. O delineamento experimental foi em faixas, com três repetições. Os tratamentos foram constituídos pela combinação de três sequências de culturas de verão (rotação soja-milho, monocultura de milho e monocultura de soja) com sete culturas de entressafra (milho, sorgo, girassol, crotalária, guandu, nabo forrageiro e milheto). O experimento foi iniciado em 2002 e o presente estudo se refere aos anos agrícolas 2008/2009 e 2009/2010. Avaliaram-se as quantidades de matéria seca e acúmulo de N, P, K, Ca, Mg e S pelas culturas de entressafra, bem como a dinâmica de decomposição e liberação dos nutrientes, por meio da utilização de sacolas de decomposição, com os seguintes períodos de avaliação: 15, 30, 60, 120 e 180 dias. A cobertura do solo foi avaliada após o manejo e ao final de cada ano agrícola. Amostras de solo foram coletadas nas camadas 0-10, 10-20 e 20-30 cm de profundidade em duas ocasiões, antes da semeadura das culturas de entressafra, em março, e de verão, em outubro, nos anos de 2008 e 2009. As amostras de solo foram submetidas às análises químicas para determinação dos teores...
In no-tillage system, the offseason crops residues are expected to maintain the soil covered in order to control soil erosion and to promote the nutrients cycling. The objective of this study was to evaluate the offseason crops dry matter quality and production, soil cover, residues decomposition and nutrient release and their effects on soil fertility, C content of humic substances, particulate and mineral associated organic matter fractions and summer maize and soybean yield. A field experiment has been carried out on a Rhodic Eutrudox at Jaboticabal, SP, Brazil (48°15’22’’ W and 21°18’58’’ S). A randomized split-block design with three replications was used. The treatments were the combination of three summer crops sequences (soybean-corn rotation, monoculture of corn and monoculture of soybean) with seven offseason crops (maize, grain sorghum, sunflower, sunn hemp, pigeon pea, oilseed radish and pearl millet). The cultivations started in 2002 and this study is related to 2008/2009 and 2009/2010 growing seasons. The offseason crops dry matter production and N, P, K, Ca, Mg and S accumulations were evaluated at management moment. The period of time to measure the residue decomposition and the nutrient release was 15, 30, 60, 120 and 180 days, using litter bags. The soil cover was evaluated after the offseason crops management and at the end of each growing season. The soil was sampled at 0-10, 10-20 and 20-30 cm soil depths in two occasions, before the offseason crops sowing, at March, and before the summer crops sowing, at October, in 2008 and 2009. Total organic C, pH, P, K, Ca, Mg and H+Al were determined in each soil samples. The soil samples obtained on October at 0-10 cm were submitted for physical and chemical organic matter fractionation, for particulate, mineral-associated, humic acid, fulvic acid and humin C content determination. The summer monoculture... (Complete abstract click electronic access below)

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Pigatin, Lívia Botacini Favoretto. "Estudo químico e espectroscópico da dinâmica da vermicompostagem de resíduos agroindustriais para manejo sustentável em agricultura orgânica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-05072017-143344/.

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A destinação dos resíduos sólidos constitui um sério problema ambiental para a humanidade. Por meio do processo de vermicompostagem, pode-se obter a reciclagem dos resíduos orgânicos, resultando em um material mais humificado, de grande potencial agrícola e de sequestro de carbono atmosférico quando aplicado ao solo. Para que se tenha segurança agronômica quando da utilização de resíduos é necessário que se conheçam os mecanismos de incorporação, mineralização e liberação de nutrientes, ou seja, a dinâmica da matéria orgânica no solo. Dessa forma, contribui-se para a manutenção do ciclo da matéria orgânica (devolvendo ao solo parte da matéria orgânica que lhe é tirada), e também para uma destinação ambientalmente adequada de resíduos orgânicos. Esta é a orientação geral deste estudo. Compilando os resultados obtidos por métodos convencionais e técnicas espectroscópicas para caracterização das amostras coletadas durante a vermicompostagem dos ácidos húmicos extraídos, foi possível fazer o monitoramento contínuo do processo de degradação de diferentes resíduos orgânicos (bagaço de laranja, torta de filtro e esterco bovino). Para execução dos experimentos foram montadas 9 pilhas (P) de compostagem de bagaço de laranja + esterco bovino, torta de filtro + esterco bovino e esterco bovino (100%). Após a estabilização da temperatura os compostos foram tranferidos aos vermicompostores. O monitoramento foi realizado por 135 dias com medidas diárias de temperatura, controle semanal de umidade e coletas quinzenais das amostras para caracterização química e extração de ácidos húmicos. Observaram-se três fases de temperatura durante a primeira etapa da vermicompostagem (compostagem). Primeira fase: mesofílica, em que houve um aumento na temperatura, a qual alcançou valores superiores a 30 °C; segunda fase: termofílica, em que a temperatura atingiu valores máximos, superiores a 60 °C para as pilhas P1, P2 e P3 (bagaço de laranja + esterco bovino), as quais apresentaram as temperaturas mais altas dentre os tratamentos; terceira fase: esfriamento e maturação. Foi possível acompanhar a dinâmica do processo de vermicompostagem química e espectroscopicamente. A caracterização química dos vermicompostos (teor de C e N, C/N, pH, CTC, macro e micronutrientes) está de acordo com o que é exigido pela Instrução Normativa no 25, do Ministério de Agricultura, Pecuária e Abastecimento. Estas análises evidenciaram o potencial fertilizante dos vermicompostos produzidos. A análise das características estruturais dos ácidos húmicos revelou diferenças entre os ácidos húmicos estudados. Os espectros de FTIR referentes a todos os tratamentos apresentaram bandas típicas de substâncias húmicas indicando algumas transformações a nível molecular como a perda de estruturas mais lábeis devido ao processo de biodegração. A presença de sistemas aromáticos foi observada por meio da técnica de UV-Vis, principalmente por meio das baixas razões E2/E4, o que é indicativo da presença de estruturas porfirínicas relacionadas à lignina. Assim como os resultados apresentados por FTIR os espectros de RMN de 13C apresentam picos correspondentes à degradação de carboidratos. Houve aumento do teor de aromaticidade e diminuição do teor de alifaticidade dos AH com o tempo de vermicompostagem, exceto para os referentes ao tratamento com torta de filtro que apresentou comportamento contrário. Em geral o desenvolvimento das plantas que receberam adubação orgânica foi similar ao desenvolvimento das plantas que receberam adubação mineral comercialmente recomendada e significativamente superior ao das plantas referente ao tratamento testemunha. Para o vertissolo o efeito dos vermicompostos sobre os atributos altura e biomassa das plantas foi mascarado, possivelmente pelo alto teor de matéria orgânica naturalmente existente naquele solo. A análise cromatográfica do óleo essencial extraído do Manjericão mostrou que a adubação orgânica influenciou positivamente a produção do principal componente do óleo essencial, o linalol, havendo aumento de seu teor com o aumento da dosagem de vermicomposto aplicado, nos dois solos estudados. Dos tratamentos analisados, o referente à adubação com vermicomposto de torta de filtro + esterco bovino 30 t ha-1, em vertissolo, apresentou o maior teor de linalol (34,90 %). De modo geral constata-se a viabilidade do uso de vermicompostos de misturas de bagaço de laranja e torta de filtro com esterco bovino como alternativa ao uso de fertilizantes minerais, contudo o manejo e as implicações na nutrição de plantas e a plena produtividade das culturas ainda representa desafio importante para as pesquisas. Dentre as doses dos vermicompostos avaliadas, em geral a aplicação da dosagem intermediária (30 t ha-1 ou 3,0%) apresenta resultados superiores em termos de qualidade nutricional e da MOS, sendo dessa forma a melhor opção para manejo do solo para cultivo de Manjericão. Em estudos futuros, a dosagem 30 t ha-1 poderia ser adotada como dosagem agronômica recomendada, bem como a mistura de resíduos orgânicos agroindustriais para produção do vermicomposto.
The disposal of solid waste is a serious environmental problem for humanity. By means of the vermicomposting process, one can get the recycling of organic waste, resulting in a humified material of great agricultural potential and atmospheric carbon sequestration when applied to soil. To have agronomic security when using waste is necessary to know the mechanisms of incorporation, mineralization and release of nutrients, or the dynamics of soil organic matter. Thus, it contributes to maintaining the organic matter cycle (returning to the ground of the organic matter that is taken away), and for an environmentally proper disposal of organic waste. This is the general direction of this study. Compiling the results obtained by conventional methods and spectroscopic techniques for characterization of samples collected during vermicomposting of extracted humic acids, it was possible the continuous monitoring of the degradation process of different organic waste (orange bagasse, filter cake and manure). For execution of the experiments were set 9 cells (P) composting orange peel + cattle manure, filter cake + cattle manure and manure. After temperature stabilization compounds were tranferidos to vermicompostores. The monitoring was held for 135 days with daily measurements of temperature, humidity and weekly control fortnightly collections of samples for chemical and extraction of humic acids. They observed three stages of temperature for the first stage of vermicomposting (composting). First stage: mesophilic, wherein an increase in temperature, which reached values higher than 30° C; second phase: Thermophilic, wherein the maximum temperature reached values higher than 60° C for stacks P1, P2 and P3 (orange peel + cattle manure), which had the highest temperature among treatments; third phase: cooling and maturation. It was possible to follow the dynamics of the process of chemical and spectroscopically vermicomposting. The chemical characterization of vermicompost (C and N content, C/N, pH, CEC, macro and micronutrients) is in line with what is required by the Normative Instruction 25, the Ministry of Agriculture, Livestock and Supply. These analyzes showed the fertilizer potential of the vermicomposts. The analysis of the structural characteristics of humic acids showed differences between the studied humic acids. FTIR spectra for all of the treatments showed typical bands of humic substances indicating some changes at the molecular level as the loss of more labile structures due to the biodegradation process. The presence of aromatic systems was observed by UV-Vis technique mainly through the lower ratios E2/E4, which is indicative of the presence of porfirínicas structures related to lignin. As the results presented by FTIR the 13C NMR spectra show peaks corresponding to the degradation of carbohydrates. There was an increase of aromaticity content and decreased alifaticidade content of AH with a time of vermicomposting, except for those related to treatment with filter cake which showed opposite behavior. In general the development of the plants that received organic fertilization was similar to the development of the plants that received commercially recommended mineral fertilization and significantly higher than the plants referring to the control treatment. For the vertisol the effect of the vermicompost on the height and biomass attributes of the plants was masked, possibly due to the high content of organic matter naturally present in that soil. The chromatographic analysis of the essential oil extracted from Manjericão showed that the organic fertilization positively influenced the production of the main component of the essential oil, linalol, increasing its content with the increase of the applied vermicompost dosage, in the two studied soils. Of the analyzed treatments, the one referring to the fertilization with vermicompost of filter cake + bovine manure 30 t ha-1, in vertisol, presented the highest content of linalool (34.90%). In general, it is possible to verify the viability of the use of vermicompostos of mixtures of orange bagasse and filter cake with bovine manure as an alternative to the use of mineral fertilizers, however the management and the implications in plant nutrition and the full productivity of the crops still represents an important research challenge. Among the doses of vermicompost evaluated, in general the application of the intermediate dosage (30 t ha-1 or 3.0%) presents superior results in terms of nutritional quality and MOS, being thus the best option for soil management for cultivation Of Basil. In future studies, the 30 t ha-1 dosage could be adopted as the recommended agronomic dosage, as well as the mixture of agroindustrial organic residues for vermicompost production.

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Grillo, Renato 1984. "Chitosan/trypolyphosphate nanoparticles as a modified release system for paraquat herbicides = preparation, characterization, interaction with humic substances and evaluation of biological activity = Nanopartículas de quitosana/tripolifosfato como sistema de liberação para o herbicida Paraquat: preparo, caracterização, interação com substâncias húmicas e avaliação da atividade biológica." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314419.

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Orientador: Leonardo Fernandes Fraceto
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Os defensivos agrícolas tornaram-se alguns dos mais importantes compostos utilizados no mundo e são os principais responsáveis pelo aumento da produção agrícola. O Paraquat, um herbicida não seletivo de contato utilizado em diversas culturas no mundo, apresenta alta toxicidade para os seres vivos e considerável persistência no solo, o que fez com que ele fosse banido em alguns países. Embora os defensivos agrícolas possuam uma importante função no aumento da produção de alimentos, através do controle de pragas, eles podem gerar sérios impactos ambientais, através da contaminação dos recursos hídricos e do solo. Com o crescimento da nanotecnologia, diversos mecanismos estão sendo estudados a fim de minimizar estes danos, tais como o desenvolvimento de sistemas de liberação modificada, utilizando polímeros biodegradáveis, o qual permite um aumento no desempenho/eficiência do produto. Estudos indicam que a matéria orgânica natural presente no solo, sedimento e água podem interagir com os defensivos agrícolas e nanopartículas e consequentemente modificar o destino destas substâncias no ambiente. A presente Tese tem como objetivo principal mostrar resultados do desenvolvimento e caracterização de nanopartículas poliméricas de quitosana/tripolifosfato para liberação modificada do herbicida Paraquat, bem como, estudar a estabilidade e a toxicidade deste sistema nanoparticulado com a presença ou ausência de matéria orgânica natural (na forma de substâncias húmicas). A atividade herbicida e a sorção do herbicida nanoparticulado no solo também foram avaliados. Nanopartículas de quitosana/tripolifosfato (com ou sem Paraquat) foram preparadas pelo método de gelificação iônica e apresentaram tamanho médio, índice de polidispersão e potencial zeta de ~ 300 nm, 0,250 e 45 mV, respectivamente. A eficiência de encapsulação do Paraquat foi de 62,6 ± 0,7 % e as nanopartículas apresentaram-se esféricas e com boa estabilidade coloidal. A cinética de liberação e o ensaio de sorção no solo mostraram que as nanopartículas retardaram a difusão e a liberação do herbicida e o modelo matemático que melhor descreveu a cinética de sorção foi o de pseudo-segunda ordem. Ensaios de citotoxicidade, genotoxicidade e ecotoxicidade indicaram que a associação do Paraquat às nanopartículas reduziram o efeito tóxico, uma vez que menos herbicida foi liberado para o ambiente em função do tempo, e ainda assim a atividade herbicida foi preservada ou aumentada. A presença de substâncias húmicas naturais não alterou os parâmetros físico-químicos estudados; entretanto, mostrou que pode reduzir a genotoxicidade e a ecotoxicidade do herbicida quando associado às nanopartículas, através de modificações na dinâmica do sistema. Este trabalho possui resultados inovadores e promissores que abrem novas discussões e perspectivas para o desenvolvimento de sistemas de liberação modificada para defensivos agrícolas
Abstract: Agrochemicals have become one of the most important compounds used in the world and are the main responsible for the increase in agricultural production. Paraquat, a non-selective herbicide used in several crops in the world, has high toxicity to living beings and considerable persistence in the soil, which led to its banishment in some countries. Although agrochemicals have an important function in increasing food production by minimizing pests, they can cause serious environmental impacts through contamination of soil and water resources. With the nanotechnology growth, several mechanisms have been studied in order to minimize these damages, such as the development of modified release systems using biodegradable polymers, which allows an increase in performance/efficiency of the product. Studies indicate that the natural organic matter present in the soil, sediment and water can interact with agrochemicals and nanoparticles, and therefore, modify the destination of these substances in the environment. The purpose of the present Thesis is to show results of the development and characterization of chitosan/trypolyphosphate polymeric nanoparticles for modified release of the Paraquat herbicide, as well as to study the stability and toxicity of this nanoparticles with the presence or absence of natural organic matter (mainly in the form of humic substances). Herbicide activity and sorption of the nanoparticulate herbicide in the soil were also evaluated. Chitosan/Trypolyphosphate nanoparticles (with or without Paraquat) have been prepared by ionic gelation method and presented average size, polydispersity index and zeta potential of ~ 300 nm, 0.250 and 45 mV, respectively. The Paraquat encapsulation efficiency was 62.6 ± 0.7 % and the nanoparticles showed themselves spherical and good colloidal stability. The release kinetics and sorption test in the soil showed that the nanoparticles modified the diffusion and release of herbicide and the mathematical model that best described the sorption kinetics was pseudo-second order. Cytotoxicity, genotoxicity and ecotoxicity tests indicated that the association of Paraquat with the nanoparticles reduced the toxic effect, since less herbicide was released into the environment as function of time, but even so, the herbicidal activity was preserved or enhanced. The presence of humic substances in the medium altered the dynamic equilibrium of the herbicide in solution, and diminished the toxicity of the nanoparticle/paraquat system. This study has innovative and promising results that open new discussions and perspectives for the development of modified release systems for agrochemicals
Doutorado
Bioquimica
Doutor em Biologia Funcional e Molecular

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Thiago, Nayrê Ohana de Souza. "Utilização de métodos espectroscópicos para avaliação de ácidos húmicos extraídos de solos de diferentes sistemas produtivos de pastagens." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-01022017-154100/.

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A agropecuária pode ser uma aliada importante para a mitigação de gases causadores do efeito estufa. A recuperação direta de pastagens degradadas, a adoção do manejo intensivo das pastagens e a integração lavoura-pecuária (ILP) têm apresentado grande potencial na diminuição dos gases de efeito estufa (GEE), devido à elevada produção de massa de forragem das gramíneas tropicais, e consequentemente acumulando matéria orgânica no solo. Estudos sobre a dinâmica e estabilidade da matéria orgânica do solo (MOS) são necessários, uma vez que a MOS constitui o maior reservatório dinâmico de carbono (C) da superfície terrestre, e qualquer variação na abundância e composição desta, perfaz importantes efeitos na dinâmica que ocorre entre os sistemas de armazenamento de carbono. Pode-se avaliar as modificações químicas sofridas pela MOS utilizando suas propriedades de fluorescência. Nesse contexto, o objetivo desse trabalho foi avaliar ácidos húmicos (AH), extraídos de diferentes sistemas de manejo pecuário, e verificar se os mesmos se alteram nesses manejos. O experimento estava localizado na unidade da Embrapa Pecuária Sudeste, São Carlos-SP, sendo os sistemas de manejos o irrigado, sequeiro, em recuperação, degradado e a mata nativa como área de referência. Foram coletadas amostras de solo das cinco áreas de estudo, e posteriormente, realizou-se a extração dos AH do solo. As técnicas utilizadas na caracterização dos AH foram análise elementar (CHNS), espectroscopia de infravermelho com transformada de Fourier (FTIR), fluorescência bidimensional e tridimensional e supressão de fluorescência por metais. Em geral, a MOS presente na superfície apresentou-se mais lábil e fresca, já a MOS em camadas mais profundas se mostrou mais recalcitrante e humificada. O manejo degradado apresentou pouco acúmulo de carbono no solo, e também um AH rico em compostos aromáticos e com alto valor de humificação. Os manejos de sequeiro e em recuperação mostraram comportamento semelhante ao da mata nativa, apresentando um alto acúmulo de carbono no solo, mas uma estrutura dos AH mais lábeis, nas camadas superficiais e baixos índices de humificação. A área irrigada teve baixa incorporação de carbono no solo, igualmente à área degradada, apresentando também um AH mais humificado e com estruturas mais conjugadas. O experimento de supressão de fluorescência mostrou valores menores da constante de estabilidade condicional (K), para os manejos irrigado e degradado, mostrando que os mesmos podem ter perdido alguns sítios ativos, deixando a MOS menos reativa no solo. Em relação às análises de fluorescência tridimensional, as amostras de AH tiveram duas componentes de fluorescência, ambas de origem tipo ácido húmico terrestre. Pode-se concluir que a recuperação de áreas degradadas é um caminho viável para a estocagem de MOS, uma vez que a área em recuperação apresentou valores semelhantes aos da mata nativa, porém a estabilidade desse carbono no solo deve ser monitorada constantemente. O excesso de irrigação e a degradação de pastagens não apresentaram um comportamento positivo para a MOS, ambos os manejos deixaram a MOS com poucos sítios ligantes, muito humificada mesmo em superfície e com pouco acúmulo de carbono no solo, deixando essa matéria orgânica pouco interativa, afetando assim a produtividade do solo.
Agricultural and livestock can be a great allied important for the mitigation of greenhouse gas effect. The direct recovery of degraded pastures, the adoption of intensive management of pasture and crop-livestock integration (CLI) have shown great potential in reducing greenhouse gas (GHG) due to the high mass of forage production of tropical grasses, and thus accumulating organic matter in the soil. Studies of the dynamics and stability of the soil organic matter (SOM) is needed, since the SOM constitutes the largest dynamic carbono (C) reservoir from the land surface, and any variation in the abundance and composition thereof, adds up significant effects on the dynamics that occurs between the carbon storage systems. Can be evaluated the chemical modifications that occurred by the SOM using their fluorescence properties. In this context, the objective of this study was to evaluate humic acid (HA), taken from different livestock management systems, and verify that the HA have changes in these managements. The experiment was located in the unit Embra Pecuária Sudeste, São Carlos-SP, with the managements systems irrigated, dry, in recovery, degraded and native forest as a reference area. Soil samples were collected from five study areas, and later was carried out the extraction of soil AH. The techniques used in the characterization of HA was elemental analysis (CHNS), Fourier transform infrared spectroscopy (FTIR), two-dimensional, three-dimensional fluorescence and fluorescence quenching. In general, the SOM on the surface presented is more labile and fresh, already the SOM in deeper layers was more recalcitrant and humified. Degraded management showed little accumulation of carbon in the soil, an HA rich in aromatic compounds and with high value humification. The dry and in recovery managements showed similar behavior to that the native forest, with a high accumulation of carbon in the soil, but a structure of HA more labile, in the surface layers and low levels of humidification. The irrigated area had low incorporation of carbon in the soil, as well the degraded area, also presenting an HA more humified and with more conjugated structures. The fluorescence quenching experiment showed lower values of the conditional stability constant (K) for irrigation and degraded managements, showing that they may have lost some active sites, leaving the less reactive SOM soil. In relation to the tridimensional fluorescence analysis, HA samples had two fluorescent components, both source type terrestrial humic acid. Can be concluded that the recovery of degraded areas is a viable way to SOM storage, since that the area in recovery showed values similar to those of native forest, but the stability of carbon in the soil must be monitored constantly. Excess irrigation and pasture degradation did not show a positive behavior for SOM, both managements left SOM with few binding sites, very much humified in surface and low carbon accumulation in the soil, leaving this organic matter little interactive, affecting thus soil productivity.

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Leal, Otávio dos Anjos. "Frações e qualidade da matéria orgânica de um solo construído vegetado com gramíneas após a mineração de carvão." Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/2462.

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After the coal mining is necessary the topographic reconstruction of the area, origining constructed soils, which typically has low soil organic matter stocks (SOM). The cover crops can help to restore these stocks, improving constructed soil conditions. The aim of this study was to evaluate the effect of cover crops on the total organic carbon stocks (TOC), carbon in organic matter fractions and the organic matter quality of a soil constructed after the coal mining. Two experiments were evaluated in a constructed soil in Candiota/RS, one with six years (E6), and another with two years (E2). The treatments were cover crops: Limpograss (T1), Pensacola (T2), Tifton Grass (T3) and Brachiaria Brizantha (T4), in E6 and T1 - Vaqueiro, T2 - Brachiaria Brizantha, T3 - Tanzania, T4 - Brachiaria Humidicola T5 - Limpograss, T6 Tifton Grass, in E2. In these treatments, were collected samples in the layer from 0.00 to 0.03 m of soil. For comparison, were collected in adjacent areas, samples from a constructed soil without vegetation (T8) and samples from a natural soil (Ultisol) with native vegetation (T9). In E6 were made the chemical and physical (grain size and densimetric) fractionations of SOM, determining the total nitrogen stocks (TN), TOC and carbon fractions, analysis of Fourier transform infrared (FTIR) of humic acid (HA) and laser induced fluorescence (LIF) of whole soil. It were calculated HA percentage (HI), ratio AH/fulvic acid (HR), the carbon management index (CMI) and the humification degree of SOM (HLIF). In E2, were made the same analysis, except for chemical fractionation. In E6 the higher HA stock was observed in T4, which did not differ from T1. The same occurred in the free light fraction (FLF) and in the occluded light fraction (OLF). The HR ranged from 0.27 to 1.0 and treatments with higher HI were T1 and T4, indicating a more humified SOM. According to FTIR analysis, the HA of T1, T2 and T4 resembled the T9, while the T3 resembled the T8. The constructed soil quality was improved mainly by T1 and T4, which had the highest CMIs. Compared to T8, the plants increased the TOC, TN, carbon in organic matter fractions and CMI, however, these values were lower than those at T9. In E2, the TOC stocks did not differ between treatments, and the higher NT stock was observed in T3, not differing from T2. The T2 and T3 presented the highest carbon stocks in the free light and coarse fractions and the highest CMIs. The plants increased the TOC, NT, carbon in organic matter fractions and the CMI in comparison to T8. In both experiments, the HLIF from the treatments was highest than the T9 and smallest than T8 and independent of plant specie there was partial restore of soil quality. The species most recommended to restore the degraded areas were Limpograss and Brachiaria Brizantha in E6 and Tanzania and Brachiaria Brizantha in E2.
Após a mineração do carvão é necessária a recomposição topográfica da área, originando solos construídos, os quais normalmente apresentam baixos estoques de matéria orgânica do solo (MOS). As coberturas vegetais podem recuperar estes estoques, melhorando as condições do solo construído. O objetivo deste estudo foi avaliar o efeito de plantas de cobertura, sobre o estoque de carbono orgânico total (COT), carbono nas frações da MOS e sobre a qualidade da matéria orgânica de um solo construído após a mineração de carvão. Avaliou-se dois experimentos em um solo construído, em Candiota/RS, um com seis anos (E6), e outro com dois anos (E2). Os tratamentos constituíram-se de coberturas vegetais: Hemártria (T1), Pensacola (T2), Grama Tífton (T3) e Braquiária Brizantha (T4), no E6 e T1 Vaqueiro, T2 Braquiária Brizantha, T3 Tanzânia, T4 Braquiária Humidícola, T5 Hemártria e T6 Tifton, no E2. Amostrou-se o solo na camada de 0,00 a 0,03m nas áreas experimentais e em área adjacente, o solo construído descoberto (T8) e um solo natural (Argissolo Vermelho) com vegetação nativa (T9), para comparação. No E6 realizaram-se os fracionamentos químico e físico (granulométrico e densimétrico) da MOS, determinando-se os estoques de nitrogênio total (NT), de COT e carbono nas frações, análise de infravermelho com transformada de Fourier (FTIR) do ácido húmico (AH) e fluorescência induzida a laser (FIL) do solo inteiro. Calculou-se o percentual de AHs (HI), razão AH/ácido fúlvico (HR), o índice de manejo de carbono (IMC) e o grau de humificação da MOS (HFIL). No E2, realizaram-se as mesmas determinações, com exceção do fracionamento químico. No E6 o maior estoque de AH foi observado no T4, que não diferiu do T1. O mesmo ocorreu para as frações leve livre (FLL) e leve oclusa (FLO). O HR variou de 0,27 a 1,0 e os tratamentos com maior HI foram o T1 e o T4, indicando uma MOS mais humificada. Os espectros de FTIR dos AHs de T1, T2 e T4 assemelharam-se ao do T9, enquanto que, o do T3 assemelhou-se ao do T8. A qualidade do solo construído foi melhorada principalmente por T1 e T4 (maiores IMCs). As plantas elevaram os estoques de COT, NT, de carbono nas frações da MOS e o IMC em comparação ao T8, entretanto, estes valores foram inferiores aos do T9. No E2, os estoques de COT não diferiram entre os tratamentos e o maior estoque de NT foi observado no T3, que não diferiu de T2. Os maiores estoques de carbono na fração grosseira (CFG), na FLL e IMCs foram observados em T2 e T3. As plantas elevaram os estoques de COT, NT, carbono nas frações da MOS e o IMC em relação ao T8. Em ambos os experimentos, o HFIL dos tratamentos foi maior que o do T9 e menor do que o T8 e independente da espécie vegetal houve recuperação parcial da qualidade do solo, sendo as espécies mais recomendadas para recuperação do solo construído a Hemártria e a Braquiária Brizantha no E6 e a Tanzânia e a Braquiária Brizantha no E2.

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Kislinger, Jiří. "Korelace termoanalytických dat s primárními charakteristikami humifikovaných substrátů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-233301.

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Tato dizertační práce je napsána jako termoanalytická studie humifikovaných substrátů, tj. huminových látek a půdních vzorků, získaných z několika různých zdrojů tak, aby byl pokryt co nejširší rozsah primárních charakteristik. Práce hledá lineární korelace (s využitím Pearsonova korelačního koeficientu) mezi kinetikou termo-oxidační degradace (sledovanou pomocí termogravimetrie (TGA) a vyjádřenou konverzním časem stanoveným neizotermickou izokonverzní metodou) a standardními charakteristikami, jako je množství aromatického a karboxylového uhlíku přítomného v huminových látkách stanoveného spektroskopií nukleární magnetické rezonance (NMR). Hlavním cílem této práce je objasnit proces termo-oxidační degradace humifikované části přírodní organické hmoty a hledat závislosti mezi primární a sekundární strukturou huminových látek. Dalším úkolem je nalezení korelace mezi termogravimetrickým úbytkem hmotnosti půdních vzorků a jejich mikrobiální stabilitou měřenou v laboratorních experimentech jakožto půdní respirace (tedy uvolňování oxidu uhličitého). Účelem je zjistit, zdali vzájemné propojení vůbec existuje, a objasnit jaké druhy procesů, které provázejí půdní respiraci, je možné jednoduše odhalit pomocí TGA. Výsledky práce skýtají detailnější pohled na termickou analýzu půdních vzorků a jiných humifikovaných materiálů. Hlavním přínosem této práce je prezentace vyskytujících se aplikací termické analýzy pro charakterizaci půdní organické hmoty a dále také příspěvek k rozvoji aplikací technik termické analýzy v půdní vědě.

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Zhao, Renzun. "Management strategy of landfill leachate and landfill gas condensate." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77186.

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Studies were conducted to evaluate the impact of landfill leachate discharge on the operation of waste water treatment plants (WWTPs). Two aspects of interferences were found: one is UV quenching substances, which are bio-refractory and able to penetrate the biological treatment processes, consequently interfere the UV disinfection in WWTPs. The other one is organic nitrogen, which can pass the nitrification-denitrification process and contribute to the effluent total nitrogen (TN). Also, treatability study was conducted for landfill gas (LFG) condensate. In a laboratory study, leachate samples were fractionated into humic acids (HA), fulvic acids (FA) and Hydrophilic (Hpi) fractions, the specific UV254 absorbance (SUVA254) of the three fractions follows: HA > FA > Hpi. However, the overall UV254 absorbance of the Hpi fraction was important because there was more hydrophilic organic matter than humic or fulvic acids. It was found that the size distribution of the three fractions follows: HA > FA > Hpi. This indicates that membrane separation following biological treatment is a promising technology for the removal of humic substances from landfill leachates. Leachate samples treated in this manner could usually meet the UV transmittance requirement of the POTWs. Also, nitrogen species in landfill leachates under various stabilization states were investigated. Although the effect of landfill stabilization state on the characteristics of organic matter and ammonia is well documented, there are few investigations into the landfill leachate organic nitrogen under different stabilization stages. Ammonia was found to leach out slower than organic matter and can maintain a constant level within the first a couple of years (< 10 years). The concentration and biodegradability of organic nitrogen were found to decrease with landfill age. A size distribution study showed that most of organic nitrogen in landfill leachates is < 1 kDa. The protein concentration was analyzed and showed a strong correlation with the organic nitrogen. Different slopes of regression curves of untreated and treated leachates indicate that protein is more biodegradable than the other organic nitrogen species in landfill leachates. XAD-8 resin was employed to isolate the hydrophilic fraction of leachate samples, hydrophilic organic nitrogen was found to be more biodegradable/bioavailable than the hydrophobic fractions. Furthermore, biological and physical-chemical treatment methods were applied to a landfill biogas (LFG) condensate to explore the feasible treatment alternatives for organic contaminant and arsenic removal efficiency. Sequencing batch reactor (SBR) showed effectiveness for the degradation of organic matter, even in an environment containing high levels of arsenic. This indicated a relatively low toxicity of organic arsenic as compared to inorganic arsenic. However, for arsenic removal, oxidation-coagulation, including biological oxidation, conventional oxidation and advanced oxidation followed by ferric salt coagulation, and carbon adsorption were not effective for what is believed to be tri-methyl arsenic. Among these, advanced oxidation-coagulation showed the best treatment efficiency (15.1% removal). Only reverse osmosis (RO) could reduce the arsenic concentration to an acceptable level to meet discharge limits. These results implied high stability and low toxicity of organic arsenic.
Ph. D.

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Pathak, Ankit Bidhan. "Two - Stage AnMBR for Removal of UV Quenching Organic Carbon from Landfill Leachates: Feasibility and Microbial Community Analyses." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/84514.

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Landfilling is the most widely used method for the disposal of municipal solid wastes (MSW) in the United States due to its simplicity and low cost. According to the 2014 report on Advancing Sustainable Materials Management by the USEPA, only 34% of the total MSW generated in the US was recycled, while 13% was combusted for energy recovery. In 2014, 53% of the MSW generated, (i.e. 136 million tons) in the US was landfilled. The treatment of landfill leachates, generated by percolation of water through the landfill, primarily due to precipitation, has been found to be one of the major challenges associated with landfill operation and management. Currently, leachates from most landfills are discharged into wastewater treatment plants, where they get treated along with domestic sewage. Issues associated with treatment of landfill leachates due to their high nitrogen and heavy metal content have been widely studied. Recently, it has been observed that the organic carbon in landfill leachates, specifically humic and fulvic acids (together referred to as "humic substances") contain aromatic groups that can absorb large amounts of ultraviolet (UV) light, greatly reducing the UV transmissivity in wastewater plants using UV disinfection as the final treatment step. This interference with UV disinfection is observed even when landfill leachates constitute a very small fraction (of the order of 1%) of the total volumetric flow into wastewater treatment plants. Humic substances are present as dissolved organic matter (DOM) and typically show very low biodegradability. Removing these substances using chemical treatment or membrane processes is an expensive proposition. However, the concentrations of humic substances are found to be reduced in leachates from landfill cells that have aged for several years, suggesting that these substances may be degraded under the conditions of long-term landfilling. The primary objective of this research was to use a two-stage process employing thermophilic pretreatment followed by a mesophilic anaerobic membrane bioreactor (AnMBR) to mimic the conditions of long-term landfilling. The AnMBR was designed to keep biomass inside the reactor and accelerate degradation of biologically recalcitrant organic carbon such as humic substances. The treatment goal was to reduce UV absorbance in raw landfill leachates, potentially providing landfills with an innovative on-site biological treatment option prior to discharging leachates into wastewater treatment plants. The system was operated over 14 months, during which time over 50% of UV-quenching organic carbon and 45% of UV absorbance was consistently removed. To the best of our knowledge, these removal values are higher than any reported using biological treatment in the literature. Comparative studies were also performed to evaluate the performance of this system in treating young leachates versus aged leachates. Next-generation DNA sequencing and quantitative PCR (qPCR) were used to characterize the microbial community in raw landfill leachates and the bioreactors treating landfill leachate. Analysis of microbial community structure and function revealed the presence of known degraders of humic substances in raw as well as treated landfill leachates. The total number of organisms in the bioreactors were found to be higher than in raw leachate. Gene markers corresponding to pathogenic bacteria and a variety of antibiotic resistance genes (ARGs) were detected in raw landfill leachates and the also in the reactors treating leachate, which makes it necessary to compare these ARG levels with wastewater treatment in order to determine if leachates can act as sources of ARG addition into wastewater treatment plants. In addition, the high UV absorbance of leachates could hinder the removal of ARBs and ARGs by UV disinfection, allowing their release into surface water bodies and aiding their proliferation in natural and engineered systems.
Ph. D.

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Gomes, Rossin Bruna. "Estudo das substâncias húmicas em pedo-paisagem podzolizada na bacia do Alto Rio Negro- AM, Brasil." Thesis, Toulon, 2017. http://www.theses.fr/2017TOUL0022.

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Le but de cette étude était de comprendre le comportement des fractions d'acide fulvique et d'acide humiquedans un système de sols podzolisé, compte tenu des caractéristiques du sol et d'étudier la capacité decomplexation de Cu+ 2 et Al + 3 dans des échantillons de ces sols. Pour cela, les méthodes conventionnellesde pédologie et de Spectroscopie de l'absorbance UV-Visible, Spectroscopie Infrarouge à Transformée deFourier et Fluorescence Quenching avec le traitement CP / PARAFAC ont été utilisés pour atteindre lesobjectifs suivants: (i) déterminer les étapes de transformation du pedo-paysage à l'étude des sols et à larépartition spatiale des sols podzols et du gleysol dans un bassin hydrographique; (ii) caractériser substanceshumiques et comprendre les schémas de distribution des acides fulviens et humiques dans une séquence desol podzols le long des profils et dans les horizons du sols en tenant compte des caractéristiquesmorphologiques, de la texture, du pH, carbone variation totale et souterraine dans les horizons des solsd'une séquence de sols podzols; (iii) étudier la capacité de complexation des substances humiques (acidesfulviques et humiques) des échantillons de sol de podzols dans le bassin du Alto Rio Negro, en identifiantles composants fluorescents des substances humiques, en évaluant les capacités et les constantescomplexantes de ces substances avec les métaux Cu+ 2 et Al+ 3 et la comparaison avec les groupesfonctionnels avec la fluorescence infrarouge à transformée de Fourier (FTIR). Encore les acides fulviquessoient plus aromatiques et condensés, leur caractère est principalement aliphatique et hydrophile etsecondairement aromatique et carboxylique. Les acides humiques sont moins aromatiques et moinscondensés que les acides fulviques et sont caractérisés par des fonctions polysaccharide et éther/alcool,mais secondairement leur caractère est aliphatique et hydrophile. Ces différences sont associées à laprésence des groupes fonctionnels qui répondent aux différences dans la dynamique de complexation desmétaux, dans les complexes acide humique, la complexation des métaux Cu+ 2 et Al+ 3 est associée auxfonctions ether/alcool et CO, polysaccharides pendant la période acide fulvic la corrélation est la plus élevéeavec les groupes fonctionnels -CH, -OH et COOH carboxylique
The purpose of this study is understaning the behavior of fulvic and humic acid fractions in a podzolized soilssystem, taking into account soils characteristics and to investigate the complexing capacity of Cu + 2 and Al + 3.For this purpose, conventional pedology and spectroscopic methods, Uv-Visible absorbance Spectroscopy, FourierTransform Infrared Spectrometry (FTIR) and Quenching Fluorescence using the CP/PARAFAC treatment wereused to achieve the objectives: (i) to determine the stages of transformation of the pedo-landscape through thestudy of soils and the spatial distribution of podzolized soils and gleysol in a drainage basin; (ii) to characterize SHand to understand the distribution patterns of fulvic and humic acids in a podzolized soil sequence along a slopeand in the horizons along the soil profiles taking into account the morphological characteristics, texture, pH, carbontotal and groundwater variation in the horizons of the soils of a sequence of podzols soils; (iii) to study thecomplexing capacity of humic substances (fulvic and humic acids) of podium soils samples in the Alto Rio NegroBasin, by identifying the fluorescent components of humic substances, evaluating capacities and complexingconstants of these substances with the Cu + 2 and Al + 3 metals, and the comparison with the functional groupsobtained with FTIR. Although fulvic acids are more aromatic and condensed their character is predominantlyaliphatic and hydrophilic and secondarily aromatic and carboxylic. Humic acids are less aromatic and lesscondensed than fulvic acids and are characterized by polysaccharide and ether/alcohol functions, but secondarilytheir character is aliphatic and hydrophilic. These differences are related to the presence of the functional groupsthat are responsible for the differences in the complexation dynamics of the metals, in the humic acids complexesCu+ 2 and Al+ 3 are associated with the functional groups ether/alcohol and CO polysaccharides while in the fulvicacids the correlation is greatest with the functional groups -CH, -OH and carboxylic COOH

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Wongwatcharapaiboon, Jitiporn. "Experimental investigations of indoor air particular matter in hot and humid climates." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/41531/.

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Throughout the era of globalization, industrial development and transportation have brought about hazardous air environment especially in developing countries. Southeast Asia with large number of labor and natural sources has expanded manufacturing area as well as the problem of local community being reluctant air pollutant. It seems to be double suffocation with emitting frequently forest fire fume covering some parts of Thailand and Indonesia. These reasons can lead to around 5-time exceeding of annual standard in the National Ambient Air Quality Standards (NAAQs). Without fresh ventilation, filtration has become more important but it may be not affordable for low income people. So this study aims to develop low cost air dust purifier being suitable for hot and humid climate based on NAAQs and BS EN. Based on low cost and general air purifying techniques, fabric filter and solid fibre mop were selected for air cleaning efficiency evaluation in laboratory. For fabric filter, in one cubic meter wooden box, pleated fabric filter was installed in the middle of box and body spray was sourced as air particulate matter sized 2.5 micron (PM2.5). The result demonstrates air cleaning efficiency of fabric filter at 85% with high fan speed. This is equal F7 in BS EN and MERV 16 in NAAQs for fine dust filtration. Turning to solid fibre mop evaluation, mops with several sizes of fibre diameter in particular (A) 0.08-0.58 mm, (B) 0.22 mm and (C) 0.16 mm were installed in the middle of box sized 0.41 m width, 0.51 m length and 0.45 m height. The results show the highest efficiency to clean PM2.5 and PM10 at 36% in mop C and 25% in mop B respectively. Moreover, multiple mops C and A have high rapidity of air PM2.5 removal at 0.050 mg/sec in 300 seconds; while multiple mops B and C have high rapidity of air PM10 removal at 0.005 mg/sec in 300 seconds. According to performance to clean PM2.5 and PM10, mop B with TiO2 coating on solid fibre was selected to integrate within filter lamp. Environmental factors are found to affect PM2.5 concentration in different trend. Temperature responded negatively; while relative humidity provided positive relationship to PM2.5 concentration. In most case of solid fibre mops tests, relative humidity dropped PM2.5 removal efficiency, but increase PM10 removal efficiency. However, high relative humidity and temperature in the filter lamp tests were set high as same as in tropical climate. After laboratory tests, fabric filter was combined within floor lamp as lamp shade and solid fibre mop was set in the middle core of lamp with coated TiO2 2.0% concentration and UV light bulb. Fan unit was set in the bottom of lamp in order to control system flow speed in application system. The application was placed in 2.5x2.5x2.5 m3 bedroom for cleaning indoor PM2.5 in six different algorithms comparing to existing PM2.5 concentration. The best efficiency of PM2.5 removal is 99.07% of regime F with fabric filter, TiO2 coating mop and fan speed at 3 m/s. This is also ranked into F9 in BS EN and MERV16 in NAAQs for fine dust cleaning filtration. Without photocatalytic process in regime B, C and D, the application could be used in lower efficiency. Higher fan speed was substantial effect on PM2.5 removal efficiency and rapidity for filter lamp. This filter lamp was found high efficiency to clean indoor PM2.5 in hot and humid condition. Based on low cost development, this application can be applied with natural ventilation system in buildings in Southeast Asia hot and humid climate. Also other conditional climate buildings may integrate this application with lower air cleaning efficiency.

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Ferreira, Fernando Perobelli. "Caracterização das substâncias húmicas extraídas do solo do manguezal de Pai Matos (Cananéia, SP, BR) e de marismas da Espanha (Galícia e Valência)." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-15102008-084016/.

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Os objetivos deste estudo foram: 1) avaliar por meio da análise elementar (C, N, H, S, O), Ressonância Paramagnética Eletrônica (RPE), e Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) às características dos ácidos húmicos (AHs) extraídos do solo do manguezal de Pai Matos (Cananéia-SP-BR) sob diferentes tipos de vegetação (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) e condições de redução, bem como às características dos AHs extraídos do solo de marismas espanholas também sob diferentes tipos de vegetação (Galícia: Spartina maritima, Juncus maritimus e Phragmites australis; Valência: Phragmites australis e Scirpus maritimus) e condições de redução; e 2) avaliar por meio da Pirólise-associada à cromatografia gasosa/espectrometria de massas (Pi-CG/EM) às características da matéria orgânica (MO) extraída do solo destes ecossistemas sob os mesmos tipos de vegetação e condições e redução. O carbono orgânico total, o nitrogênio total, o enxofre total e os valores de Eh e pH dos solos estudados também foram analisados. Os resultados mostraram que o ambiente predominantemente redutor dos solos estudados ocasionou uma maior incorporação de N e S e uma menor concentração de radicais livres semiquinona (CRLS) em relação aos AHs derivados de solos de ecossistemas terrestres, sugerindo desta forma, a presença de uma matéria orgânica (MO) menos humificada no solo das áreas de estudo; entretanto, somente os AHs extraídos do solo do manguezal apresentaram uma maior razão atômica H/C e O/C em relação aos AHs derivados de solos terrestres. A CRLS também foi maior nos AHs das camadas subsuperficiais dos solos estudados, sugerindo que o ambiente mais anóxico ocasionou um maior grau de humificação da MOS destas camadas, entretanto, como os manguezais e as marismas são ambientes de sedimentação, a contribuição de uma matéria orgânica mais humificada de origem terrestre previamente depositada nas áreas de estudo também pode ter ocasionado este resultado. Entre as diferentes vegetações estudadas, foi observada uma maior relação C/N e CRLS dos AHs extraídos do solo sob Rhizophora e Avicennia (manguezal) e uma maior relação C/N dos AHs extraídos do solo da marisma de Valência-ES, sugerindo uma maior recalcitrância da MOS sob estas vegetações. Os espectros de FTIR não permitiram verificar variações significativas na composição química e estrutural dos AHs obtidos dos solos sob as diferentes vegetações e condições de redução; entretanto, observo-se através da Pi-CG/EM uma maior concentração de compostos lignificados na MO extraída do solo sob Avicennia e Rhizophora (manguezal) e da marisma de Valência-ES, também sugerindo uma maior recalcitrância e menor humificação da MOS destas áreas de estudo. Além disso, observou-se que a maior decomposição da MOS ocasionou o decréscimo no conteúdo de lignina com o acréscimo relativo de compostos alifáticos; o acréscimo dos compostos alifáticos de cadeia curta em detrimento ao acúmulo dos de cadeia longa; a perda da dominância dos alcanos/alquenos de cadeias ímpares em relação aos de cadeias pares; e o acréscimo de compostos orgânicos de origem microbiana nos solos estudados.
The goals of this study were: 1) evaluate by elemental analysis (C, N, H, S, O), Electronic Paramagnetic Resonance (EPR), and Fourier transformed infrared spectroscopy (FTIR) the characteristics of the humic acids (HA) extracted from the soil of Pai Matos mangrove forest (Cananéia, SP, BR) under different vegetation types (Rhizophora mangle, Avicennia schaueriana, Laguncularia racemosa, Spartina alterniflora) and soil reduction conditions, as well as the HA extracted from Spanish salt marsh soils (Galícia and Valência) under different vegetation types (Galicia: Spartina maritima, Juncus maritimus, and Phragmites australis; Valencia: Phragmites australis e Scirpus maritimus) and soil reduction conditions; and 2) evaluate by Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique the characteristics of the SOM extracted from the these study areas under the same vegetation types and reduction condition. The total organic carbon, the total nitrogen, the total sulfur, and the soil pH and Eh in the field also were analyzed. The results showed that the predominantly anoxic soil condition caused the higher N and S content in the HA of both study areas than the HA derived from terrestrial soils and marine environments, and that the studied HA also showed a lower semiquinone-type free radical (SFR) content than terrestrial soils, thus suggesting a lower humification degree of the SOM derived from the study areas; however, only the HA derived from de mangrove forest soil showed a higher H/C and O/C atomic ratio than the HA derived from the terrestrial soils and marine environments. In addition, the SFR content also was lower in the surface soil layers, suggesting the input of a fresh and labile plant-derived organic matter as responsible by the lower humification degree of the SOM derived from these layers; however, as mangroves and salt marshes are sedimentation environments, it is likely that besides the more anoxic soil condition, a more humified organic matter (OM) derived from terrestrial soils also may cause the highest SFR content observed in the subsurface soil layers. Among the different vegetation types, also was observed a higher C/N ratio of the soil and HA derived from Valencian salt marsh, as well as both a higher C/N ratio and SFR content in the HA extracted from the soil under Rizhophora and Avicennia (mangrove), suggesting a more recalcitrant SOM in these sites. The FTIR spectras did not show significant variation among vegetation types and soil depths, and finally, by the Py-GC/MS technique was observed that the OM derived from the Valencian salt marsh soils and from the soil under Avicennia and Rhizophora (mangrove) showed a more recalcitrant SOM (higher lignin content) than the SOM derived from the soil under the other vegetation types studied. In addition, it was also observed that the SOM decomposition caused a decrease in lignin contents and a relative increase in aliphatics; an increase in short-chain aliphatics at the expense of longer ones; a loss of odd-over-even dominance in the n-alkanes and n-alkenes; and an increase in microbial products in the studied soils.

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Solanský, Pavel. "Využití chromatografie na tenké vrstvě k frakcionaci a charakterizaci organické hmoty izolované z alginitu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445143.

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This diploma thesis is focused on the study of structure and physicochemical properties of organic fractions of humic substances, which were obtained by the method of thin-layer chromatography. Humic substances, which were used in this study, were isolated from a sample of Slovak alginite based on the procedure of the International Humic Substances Society (IHSS). The following analytical techniques were selected for the characterization of isolated humic substances: thermogravimetric and elemental analysis, molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. Each organic fraction of humic substances were characterized by molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy. Using steady-state fluorescence spectroscopy, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorophores were characterized by a higher content of oxygen substituents on the aromatic nukleus, a higher degree of aromaticity and also a higher molecular weight. The aim of this diploma thesis was to design and optimize the process of organic matter fractionation for the purpose of detailed understanding of the structure and properties of humic substances, which were isolated from the sedimentary rock alginite. Based on this, the practical applicability of the thin layer chromatography method to significantly reduce the molecular heterogenity of the studied humic substances was evaluated.

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Macuráková, Viktória. "Interakce půdní organické hmoty s polutanty studovaná mikrokalorimetrickými technikami." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433051.

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This diploma thesis dealt with the study of interactions of soil organic matter, specifically humic acids with a pollutant, where the surfactant Septonex was used. Humic acids were isolated from two different soils in the work, namely black earth and cambium. The theoretical part describes the formation of humic acids as such, their possible interactions with substances and the characterization of surfactants. The experimental part is devoted to the characteristics of humic acids using elemental analysis, thermogravimetry and then the most important part of the thesis, namely the monitoring of interactions using isothermal titration calorimetry. The experiment showed that the sample of isolated black earth at the surfactant concentration of 0,075 moldm3 had the best interaction with the surfactant.

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Catrouillet, Charlotte. "Les interactions entre l'arsenic, le fer et la matière organique en milieu anoxique." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S043/document.

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L'arsenic est un élément toxique présent naturellement dans l'environnement. Parfois en fortes concentrations dans les eaux souterraines, utilisées comme eaux de boisson, il est responsable d'une des plus grandes mortalités au monde. Il est donc important de mieux comprendre les interactions de l'As avec l'environnement et son mode de transfert jusqu'aux aquifères. Cette thèse a pour objectif de comprendre les mécanismes de complexation direct et indirect de l'As(III) par la matière organique (MO) en milieu anoxique, notamment via les groupements thiols de la MO et sous forme de complexes ternaires faisant intervenir le Fe ionique. La première partie de ce travail a été consacrée à la complexation de l'As(III) par les groupements thiols de la MO. Des expériences de complexation d'As(III) par un acide humique (AH) naturel greffé ou non en sites thiols ont été réalisées. L'As(III) se complexe à la MO directement mais les concentrations complexées sont faibles et dépendantes de la densité en site thiol. La modélisation à l'aide de PHREEQC-Model VI modifié afin de tenir compte des sites thiols, a mis en évidence que l'As était complexé à la MO sous forme de complexes monodentates. Il existe, un autre mécanisme qui propose une complexation indirecte via la formation d'un pont cationique. Nous nous sommes intéressés ici, en conditions anoxiques, à la possibilité que ce pont soit un pont de Fe(II). Il n'existe cependant que très peu d'information sur la complexation du Fe(II) par la MO. Des expériences de complexation du Fe(II) par des substances humiques (SH) ont donc été réalisées. Les résultats expérimentaux ont montré que le Fe(II) est faiblement complexé aux SH lorsque le pH était acide et les groupements fonctionnels protonés. Au contraire à pH neutre à basique, 100% du Fe(II) est complexé aux SH. La modélisation a montré que le Fe(II) forme majoritairement des complexes bidentates carboxyliques à pH acides et des complexes bidentates carboxy-phénoliques et phénoliques à pH basiques. Dans la dernière partie, la complexation de l'As(III) par des complexes ternaires As(III)-Fe(II, III) ionique-MO a été testée. Les résultats expérimentaux ont montré que des complexes ternaires As(III)-Fe(II)-MO pouvaient se former en milieu anoxique. La modélisation a permis de tester différentes conformations structurales de complexes ternaires. Le complexe le plus probable est un complexe bidentate mononucléaire d'As(III) sur un complexe bidentate de Fe(II)-AH. Cependant, PHREEQC-Model VI doit être amélioré car la distribution des sites bidentate n'est pas réaliste en comparaison des données spectroscopiques. Au contraire pour de faibles concentrations en Fe(III), l'As(III) ne forme pas de complexes ternaires As(III)-Fe(III) ionique-MO. La spéciation de l'As et du Fe est particulièrement importante dans l'étude du transfert de l'As. Si l'As(III) est complexée à la MO, son transfert dépendra totalement des mécanismes de transfert de la MO
Arsenic occurs naturally in groundwater used as drinking water. It is thus responsible of a great mortality in the world. Understand the As interactions with its environment and its transfer mode to the aquifers is therefore crucial. This work was focused on the direct and indirect binding mechanisms of As(III) by organic matter (OM) in anoxic environments, in particular via OM thiol groups and as ternary complexes involving ionic Fe. The first part of this work was dedicated to the complexation of As(III) by the OM thiol. Binding experiments of As(III) by a humic acid (HA) grafted or not by thiol were thus performed. Grafted or not OM were able to bind As(III) but bound As(III) concentrations were low and dependant on the thiol site density. Modeling with PHREEQC-Model VI modified to take into account thiol site demonstrated that As(III) was bound as monodentate complexes to OM thiol sites. Another indirect binding mechanism involving ternary complex via cationic bridge was however described to explain larger binding of As(III, V) to natural OM. Here under anoxic conditions, we speculated that this bridge was an ionic Fe(II) bridge. However, little information exists about the binding of Fe(II) by OM. Complexation experiments of Fe(II) by humic substances (HS) were thus conducted. The experimental results showed that Fe(II) was weakly complexed to HS at acidic pH, when the functional groups were protonated. By contrast, at basic pH, 100% of Fe(II) were complexed to HS. Modeling calculations demonstrated that Fe(II) formed mainly carboxylic bidentate at acidic pH and carboxy-phenolic and phenolic bidentate at basic pH. In the last part, the complexation of As(III) as As(III)-ionic Fe(II, III)-OM ternary complexes was tested. Experimental results showed that As(III)-Fe(II)-OM ternary complexes could form in anoxic environments. Modeling allowed to test several ternary complexes conformations. The most potential was the binding of As(III) as mononuclear bidentate complex onto a bidentate Fe(II)-AH complex. However, another definition of the model that should be constrained by XAS data is required. By contrast, at low concentrations of Fe (III), when the oxidizing and reduced species coexist, As(III) does not form As(III)-ionic Fe(III)-OM ternary complexes. Speciation of As and Fe is particularly important in the study of the As(III) transfer. When As(III) is bound to OM as ternary complexes, its transfer is entirely controlled by the own OM transfer mechanisms. Here, we calculated, however, that much of As(III) remains as labile species and can therefore reach underlying aquifers as long as anoxic conditions exist

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Hofmann, Heidrun. "Die Eluate des mikrobiellen Abbaus organischer Massen in ihrer chemischen Zusammensetzung und ihrer Kopplung mit freigesetzten Asche-Anteilen." Doctoral thesis, [S.l.] : [s.n.], 2005. http://hdl.handle.net/11858/00-1735-0000-0006-AB77-0.

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Terdkiatburana, Thanet. "Simultaneous removal process for humic acids and metal ions by adsorption." Curtin University of Technology, Dept. of Chemical Engineering, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=18564.

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Humic substances are macromolecules that naturally occur in all environments in which vegetation matter are present. In general, humic acid is part of humic substances which form the major fraction of the dissolved organic matters in surface water and represents 90% of dissolved organic carbon. Humic acid plays a fundamental role in many ecosystems since it interacts with toxic metal ions present in the system, resulting in a decrease in the bio-availability of such ions. Moreover, the availability of humic acid in water can react with other chemical compounds, such as chlorine to form trihalomethanes (including chloroform) and causes an increasing risk of cancer and may be linked to heart, lung, kidney, liver, and central nervous system damage. Therefore, humic acid removal in water treatment processes is very important in order to achieve the drinking water standards. Heavy metals are significant contaminants in aqueous system. All heavy metals can produce toxicity when ingested in sufficient quantities, but there are several important ones such as lead, mercury, copper, cadmium, arsenic, nickel and silver. These heavy metals are so pervasive and produce toxicity at low concentrations. Moreover, they may build up in biological systems and become a significant health hazard.
Adsorption is approved as an effective and simple method for water and wastewater treatment process. Many adsorbents then are developed for use in adsorption process such as montmorillonite, peat, activated carbon, etc. In this research, humic acid and heavy metals were mainly selected for adsorption study. In the sorption experiment, several adsorbents such as synthesised zeolite (SZ), natural zeolite (NZ), powdered activated carbon (PAC) and fly ash (FA), were selected to examine the application of HA and heavy metals both in individual and simultaneous adsorption, The characteristics and interactions of the adsorbents with HA and heavy metals were systematically studied by batch laboratory experiments. In the beginning, the adsorption of HA onto SZ, NZ, PAC and FA was investigated and their adsorption capacity was compared. The equilibrium adsorption of HA on SZ, NZ, PAC and FA was found to be 84.1, 67.8, 81.2 and 34.1 mg/g, respectively, at 30 oC and pH 5.0. Dynamic adsorption data show that these adsorbents could reach their adsorption equilibrium after 50 hours. From pH analysis, HA adsorption is favoured at low pH and an increase in pH will lead to the reduction of HA adsorption. SZ and NZ adsorption capacity were affected by the changing of solution temperature; however, in PAC and FA sorption study, there was no significant effect observed. Two heavy metal ions (Cu, Pb) removal by the adsorbents was then conducted. The results showed that the equilibrium sorption capacity of Cu and Pb ions on SZ, NZ, PAC and FA were 43.5, 24.2, 19.7, 28.6 and 190.7, 129.0, 76.8 mg/g, respectively at 30 oC and a pH value of 5. The appropriate pH for Cu and Pb removal was found to be 5 and 6. In most dynamic cases, these adsorbents needed at least 50 hours to reach the adsorption equilibrium. Only adsorption on FA required more than 150 hours to reach the equilibrium.
In simultaneous adsorption experiments, the influences of HA and heavy metal concentration (in the range of 10 to 50 mg/L for HA and 10 to 30 mg/l for heavy metals) on the HA-heavy metal complexation were investigated. The results demonstrated that increasing HA concentration mostly affected Cu adsorbed on SZ, FA and PAC and Pb adsorbed on SZ, NZ and PAC. For HA adsorption, the adsorption rate decreased rapidly with increased initial metal ion concentration. Moreover, the adsorption of heavy metals increased with increased heavy metals concentration in the presence of HA. In the presence of heavy metal ions, the order of HA adsorption followed PAC > FA > SZ > NZ. According to the results, the individual and simultaneous adsorption of HA and heavy metals on each adsorbent achieved a different trend. It mainly depended on the adsorption property of both adsorbates (HA and heavy metals) and adsorbents (SZ, NZ, PAC and FA) and also the operation factors such as pH, concentration, temperature and operation time. Even though this experiment could not obtain high adsorption performance, especially in coadsorption, as compared with other adsorbents, the adsorbents in this study represented a higher adsorption capacity and provide the potential for further development.

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Bernhard-Bitaud, Corinne. "Modifications de la matière organique et conséquences sur l'adsorption de l'atrazine dans un sol brun de prairie mis en culture." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL128N.

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En conditions de plein champ après retournement d'une prairie permanente, on compare pendant cinq ans l'évolution des propriétés d'un sol brun entre deux parcelles, l'une exempte de tout traitement chimique, l'autre désherbée à l'atrazine. On observe au cours du temps une diminution de la stabilité structurale (-30%) et de la teneur en matière organique (- 20%), ainsi qu'une augmentation du rapport isotopique ¹³C/¹²C, du taux d'humification et de l'extractibilité des acides humiques. Toutefois, l'étude des caractéristiques chimiques de la matière organique ne révèle pas de différence majeure entre les deux parcelles tout au long des cinq années. Un fractionnement des agrégats à 50 [micro]m permet de mettre en évidence une plus grande richesse en carbone de la fraction grossière (50-2000 [micro]m) du sol non désherbé par rapport au sol traité, qui peut être attribuée aux importants retours de matière organique fraiche par les adventices. Ces derniers n'affectent cependant pas les caractéristiques qualitatives des matières organiques totales ; ainsi le rapport C/N reste constant et identique dans les deux parcelles. L'analyse en spectroscopie d'absorption infra-rouge des acides humiques et fulviques extraits montre que les groupements fonctionnels des composés humifiés ne sont affectés de façon majeure ni par l'évolution générale du sol ni par le traitement à l'atrazine. Cependant, l'étude de la cinétique d'adsorption de l'atrazine met en évidence une diminution de la vitesse de mise à l'équilibre entre les échantillons les plus anciens et les plus récents. Par ailleurs, la comparaison de l'adsorption entre la fraction fine (0-50 [micro]m) et la fraction grossière (50-200 [micro]m) d'un même échantillon de sol montre que l'adsorption est moins rapide mais également moins réversible sur la fraction grossière. Ces différences de comportement rendent compte de variations très fines de la réactivité des matières organiques, et sont commentées en relation avec la structure hypothétique du complexe argilo-humique

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46

Pontoni, Ludovico. "Accumulation and colloidal mobilization of trace heavy metals in soil irrigated with treated wastewater." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1144/document.

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La réutilisation des eaux usées traitées pour l’irrigation est globalement acceptée et pratiquée pour faire face à la pénurie d'eau et économiser les ressources de haute qualité. Bien que cette pratique présente des avantages indéniables et contribue à un usage plus durable de l'eau douce, elle n’est pas exempt de problèmes liés à l'impact potentiel sur la qualité des sols récepteurs et sur les cultures de micropolluants contenus dans l'eau réutilisée. Parmi ces polluants, les métaux lourds (ML) en concentrations traces jouent un rôle primordial en raison de leur présence systématique dans l'eau utilisée et de leur persistance une fois libéré dans l'environnement. Le devenir des ML dans les sols peut difficilement être prédit parce que les mécanismes de mobilité à travers les sols sont extrêmement variés et liés à des phénomènes simultanés et très complexes impliquant différents équilibres chimiques. Les ML, comme beaucoup d'autres contaminants, ne sont pas seulement partagé entre la phase immobile (le sol) et les phases mobiles présentes dans l'eau. En effet, les colloïdes et les nanoparticules agissent comme une troisième phase mobile, avec leurs propres propriétés rhéologiques et des vitesses de migrations qui leur sont propres. Ce dernier aspect a été l'un des principaux objectifs d’étude de la thèse. Plusieurs essais expérimentaux ont été menés en irriguant un sol standard selon l'Organisation de coopération et de développement économiques (OCDE) avec une eau usés traités réel et / ou synthétiques, contenant des ML en concentrations traces. Pour chaque test, un sol spécifique (avec différentes teneurs en matière organique) et des eaux usées traitées de composition différente (avec différentes concentrations en métaux traces, de salinité, de la teneur en matière organique pour les eaux usées synthétiques, ou des eaux usées traitées réelles) ont été choisi afin d'évaluer les effets des conditions différentes sur le devenir global des ML. L'augmentation de la matière organique du sol de 2,5 à 10% a linéairement amélioré la mobilité des Cd, Cu et Ni avec une augmentation de la mobilité maximum de 35,6, 43,7 et 49,19% pour le Cd, Cu et Ni, respectivement. Pour la plupart des expériences, les ML ont été capturés dans la couche superficielle du sol (0,5 à 1 cm). Néanmoins, des pics de contamination ont été détectés à des profondeurs différentes dans les couches plus profondes du sol. L’étude de la composition des lixiviats montre des variations de concentrations fonction du métal étudié et des caractéristiques du sol et des eaux usées. Des pics de métaux dans le lixiviat sont apparus en même temps que la libération de la matière et / ou la libération de silicates organiques, ce qui démontre l'implication significative des colloïdes dans le transport des métaux. La concentration en sodium (20 mM) a été démontrée un impact fort sur la réduction de la mobilisation colloïdale et que plus de 95% du métal apporté a été détecté dans la couche superficielle du sol en dépit de sa teneur en matière organique. La salinité affiche donc des effets significatifs. L'irrigation avec des eaux usées traitées présentant une très haute teneur en Ca et Mg (111 et 134 mg / L, respectivement) a abouti à la libération moyenne plus élevée de silicium à partir de la matrice inorganique du sol (8,2 mg / L) par rapport à la faible salinité des eaux usées artificielle (1,9 mg / L). Par conséquent, la mobilisation ultérieure de Cd, Cu, Ni et Zn a été observée lorsque le sol a été irrigué avec des eaux usées traitées réelles. Une caractérisation spectroscopique avancée des lixiviats a été réalisée pour identifier les agrégats colloïdaux libérés par le sol dans le but d’en déterminer leur nature, leurs propriétés chimiques et leur état d'agrégation
Reuse of treated wastewater for agricultural purposes is worldwide accepted and practiced to face water scarcity and save high quality resources. Although such practice has undoubtable advantages and is certainly more sustainable respect to the use of fresh water, it is not exempt from severe concerns related to the potential impact on the receiving soil and on the crops of potentially harmful pollutants contained in the reused water at trace levels. Among these pollutants, trace heavy metals (HMs) play a primary role due to their spread presence in the used water and to their persistence once released in the environment. The fate of HMs in the soils can be hardly predicted as mechanisms of mobility through soils are extremely diverse and related to highly complex simultaneous phenomena and chemical equilibria. HMs, in fact, as many other contaminants, are not only partitioned between the solid immobile and the water mobile phases. Indeed, colloids and nanoparticles act as a third mobile phase, with their own rheological properties and velocity. This latter aspect has been one of the main focus of the thesis. In details the thesis describes the results of several experiments conducted irrigating the OECD standard soil with real and/or synthetic wastewater, containing HMs in trace. For each test a specific soil (e.g. varying the organic matter content) and wastewater composition (e.g. varying the metals concentration, the salinity, the organic matter content, or testing real treated wastewaters) has been chosen in order to evaluate the effects of different conditions on the overall HMs fate. The increase of soil organic matter from 2,5 to 10% linearly enhanced the mobility of Cd, Cu and Ni up to a maximum mobility increase of 35.6, 43.7 and 49.19 % for Cd, Cu and Ni, respectively. In most experiments metals accumulated in the top soil layer (0.5 - 1 cm). Nevertheless peaks of contamination were detected at different depths in the soil deeper layers and at different leaching time in the leachates depending on the metal and on the soil and wastewater characteristics. Peaks of metals in the leachate appeared simultaneously with release of organic matter and/or release of silicates, demonstrating outstanding involvement of colloids in metals transport. Sodium concentration (20mM) decidedly reduced colloidal mobilization whereas more than 95 % of the influent metal was detected in the top layer despite the soil organic matter content. Salinity displayed different effects. The irrigation with real treated wastewater with quite high content of Ca and Mg (111 and 134 mg/L, respectively) resulted in higher average release of silicon from the soil inorganic matrix (8.2 mg/L) compared to the low salinity artificial wastewater (1.9 mg/L). Consequently higher mobilization of Cd, Cu, Ni and Zn was observed when the soil was irrigated with real treated wastewater. An advanced spectroscopical characterization of the leachates was performed to identify such colloidal aggregates. The observation of 3D excitation-emission matrix demonstrated in all the leachates samples the presence of fulvic (230-450 nm ex-em fluorescence area) and humic (330-445 nm ex-em) substances. In this context, a novel analytical method was developed to quantify phenolic substances in soil matrices allowing the monitoring of humic matter migration in soil profiles. The novel method was more accurate and more precise respect to the traditional one, allowing to obtain higher recovery of total phenols in peat soil (15.5 % increase) with a decrease of the coefficient of variation (30.1% decrease). Organic water soluble colloids were extracted from the peat used to prepare the OECD standard soil and characterized. Results of size exclusion chromatography highlighted the supramolecular structure of the extracted organic matter. Such structure was further confirmed through fluorescence and 1H-NMR spectroscopy

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47

Mediastika, Christina E. "Design solutions for naturally ventilated houses in a hot humid region with reference to particulate matter and noise reduction." Thesis, University of Strathclyde, 1999. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21430.

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Pollution in developing countries is generally much worse than in developed countries, and is caused by the widespread use of poor quality machines both industrial and in motor vehicles. Obviously, motorised vehicles are a major source of today's pollution. Motor vehicle emissions, whether gases, particulate matter or noise, can all be dangerous. Particulate matter, especially very fine particulates, is the major concern of this thesis, which considers their capacity for penetrating deep into the lungs and developing slowly to cause noticeable illnesses. Low-income people who live within the city centre are the most exposed to traffic pollution whether on the move or indoors. Low cost housing, whether self built or provided by government or private sectors, often exposes occupants to both lack of thermal comfort and pollutant intrusion from adjacent street traffic. Houses in warm-humid regions depend on large openings and through ventilation for thermal comfort. Openings allow air pollution and noise to penetrate these houses easily, thereby affecting the health, comfort and well-being of residents. Closing all openings and changing from natural ventilation to air conditioning is not however a practical solution for low cost housing. This study explores the effect of boundary fences, vegetation, and detailed opening design in reducing the penetration of airborne particulates and noise into the living spaces of typical low-cost urban houses. The experiments carried out for this study include computational simulation, manual calculation and field experiments. The research indicated that there are feasible and practical solutions to the reduction of fine particulate matter and street noise in such housing by using solid and massive barriers combined with vegetation and a specific window type. Solid and massive barriers were constructed to slow the progress of the pollutants by reduction of wind speeds on approaching obstructions. If the wind slows down enough, this effectively 'holds' the pollutant in place. In this case, the deposition surface was provided by vegetation with dense foliage. The surface of the vegetation was predicted to deposit particulate matter effectively, which would then be washed away naturally by rains. Some types of leaves were studied to find the relationship between the physical characteristics of leaf surfaces and their ability to deposit particulate matter. Before entering the living spaces, the particulate matter then encounters further obstruction by jalousie windows thus reducing its concentration. The solid and massive fence also created an acoustic shadow and noise was then further reduced by the jalousie windows. The resulting indoor noise level was found to be closer to the proposed Indonesian standards of 45 dBA.

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48

Noureddin, Seïf. "Contribution à l'étude de la matière organique dans le milieu marin côtier : Classe des substances humiques." Brest, 1988. http://www.theses.fr/1988BRES2014.

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Analyses des substances humiques dissoutes en suspension dans l'eau de mer et dans les sediments recents de l'estuaire de l'elorn en bretagne. Elles montrent que les substances dissoutes sont surtout constituees d'acides fulviques alors que les particules en suspension sont plutot constituees d'acides humiques et qu'une accumulation importante en acides fulviques dans les sediments a lieu au debut de l'ete

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49

Paula, Bruno Santos de. "Caracterização do carbono associado a horizontes espódicos profundos de solos da floresta amazônica, visando sua estabilidade." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-18082015-101731/.

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Este projeto nasceu inserido num contexto de crescentes pesquisas em direção à construção de um cabedal de conhecimento acerca das ciências ambientais que tratam e estudam a dinâmica dos reservatórios de carbono e suas contribuições para o Efeito Estufa. Extrapolações de novos mapas digitalizados de solos sugerem que os espodossolos hidromórficos da Amazônia podem estar com uma contagem de carbono subestimada em até 12,3 Pg de C e trabalhos anteriores mostram que o carbono imobilizado neste perfil pode sofrer mineralização devido ao corte na rede de drenagem ou rebaixamento do nível freático, podendo assim contribuir em grande parte para o aumento de emissão dos Gases do Efeito Estufa. Nesta circunstância, coube a este trabalho, caracterizar espectroscopicamente, a matéria orgânica estocada em profundidade em 9 perfis de solo da região de São Gabriel da Cachoeira - AM, na floresta amazônica. Foram analisadas 127 amostras em quantidade de carbono e por fluorescência induzida por laser (FIL). A partir destas análises preliminares, foi possível selecionar 12 amostras de 2 perfis para análise mais detalhada através da extração das substâncias húmicas. Foram realizadas análises para obtenção da textura destes perfis, análise dos ácidos húmicos como relação C/N, espectroscopia de infravermelho com transformada de Fourier (FTIR), RMN de 13C no estado sólido, fluorescências bidimensional e tridimensional com aplicação do método estatístico análise dos fatores paralelos (PARAFAC) e também análise dos ácidos fúlvicos como carbono orgânico total (TOC), espectroscopia na região do ultra-violeta e visível e fluorescência 3D associada ao PARAFAC. Em geral, as amostras se dividiram em 3 grupos diferentes, onde a matéria orgânica em superfície se mostrou lábil e recente, a matéria orgânica nos horizontes B húmicos se mostraram com características recalcitrantes e a matéria orgânica contida nos horizontes onde existia água livre (lençol freático), se mostraram com características diferentes, indicando não serem tão jovens quanto as em superfície, porém mais jovens do que a armazenada no Bh, devido a uma possível migração por movimentos laterais do lençol freático. A correlação entre os resultados mostrou que a textura do solo é importante para o acúmulo da matéria orgânica e conseqüentemente sua humificação. Os resultados de fluorescência corroboraram a interpretação dos dados de RMN, FTIR e textura, apontando que o Perfil 4 (mais próximo ao rio) por ter C2 maior nos horizontes intermediários, contém maior quantidade de exsudatos microbianos frescos. Para o Perfil 5, que é uma mancha de Espodossolo dentro de um Latossolo e encontra-se mais longe do rio, os fluoróforos mais representativos são oriundos de anéis aromáticos mais antigos e conseqüentemente mais humificados, devido às maiores intensidades de C1 e C3. Vale ressaltar que esta interpretação se alinha com os resultados de datação do 14C desta região. Foi notório que a humificação ocorre a partir do começo do horizonte Bh e que seu acúmulo pode ocorrer tanto nos horizontes intermediários (Bh) quanto mais os profundos (úmidos). Dessa forma, pode-se concluir que uma drenagem excessiva das bordas dos rios nesta região que acumula carbono em profundidade, poderá expor a MO guardada e estocada a longo tempo, contribuindo para o aumento da temperatura global e por conseguinte catalisando um desequilíbrio no clima da sua maior reguladora no mundo: a Floresta Amazônica.
This project was born inserted in a context of increasing research towards building knowledge about environmental science that treat and study the dynamics of carbon reservoirs and their contribution to the greenhouse. Extrapolation of new digital soil maps suggests that Amazonian hydromorphic Spodosols may be with a carbon accounting underestimated by up to 12.3 Pg of C and previous work show that the carbon fixed in this profile may suffer mineralization due to the cut in the drainage network or lowering of the water level and can contribute largely to the increased emission of greenhouse gas. In this circumstance, it was instructed to this work, the spectroscopic characterization, of the stored organic matter in depth at 9 soil profiles of São Gabriel da Cachoeira - AM, in the Amazon rainforest. 127 samples were analyzed for amount of carbon and laser-induced fluorescence (LIF). From these preliminary analyzes, it was possible to select 12 samples of 2 profiles for humic substances extraction and further detailed analysis. Analyzes were conducted to obtain the texture of these profiles, analysis of humic acids as C/N ratio, Fourier Transform Infrared Spectroscopy (FTIR), solid state 13C NMR, two and three dimensional fluorescence with applying of the Parallel factors analysis (PARAFAC) statistical method and also fulvic acid analysis as Total Organic Carbon (TOC), ultra-violet and visible region spectroscopy and 3D fluorescence associated with PARAFAC. In general, the samples were divided into 3 different groups, wherein the surface organic matter evinced labile and recent. The B humic horizons organic matter proved recalcitrant characteristics and organic matter contained in horizons which had free water (groundwater), showed different characteristic, indicating they are not so young as the surface, but younger than stored in Bh, because of possible migration by lateral movements of the water table. The correlation between the results showed that soil texture is important for the accumulation of organic matter and therefore its humification. The fluorescence results confirmed the interpretation of the NMR, FTIR and texture datas, indicating that the profile 4 (closest to the river), presenting major C2 in intermediate horizons, contains larger amount of fresh microbial exudates. To profile 5, which is a Spodosol spot within a Ferrasol and is thither from the river, the most representative fluorophores came from older aromatic rings and therefore is more humified, due to higher intensities C1 and C3. It is noteworthy that this interpretation is in accord with the results of 14C dating of samples from this region. It was clear that the humification occurs from the beginning of the Bh horizon and their accumulation can occur both in the intermediate horizons (Bh) and in deeper (wet). Thus, it can be concluded that excessive drainage of the edges of rivers in this region that collects carbon in depth, may expose the OM stored for long time, contributing to increase the overall temperature and therefore catalyzing an imbalance in the climate of the biggest regulatory of it in the world: the Amazon rainforest.

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Wright, David R. "Soil Stable Carbon Isoptope Analysis of Landscape Features at Aguateca, Guatemala." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1125.

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The ancient Maya of the Classic period (1700-1050 B.P.) relied on maize agriculture to support their populations. The agricultural systems they employed to produce that maize varied in form and degree of intensity, with more productive forms of agriculture needed in the Late Classic period (1350-1050 B.P.) to sustain the peaking population. It is likely that the ancient systems of production agriculture contributed to environmental degradation that in turn contributed to the pressures that culminated in the collapse of the civilization. In this study, stable carbon isotope ratios contained in the soil organic matter were used to further investigate ancient maize cultivation in the Petexbatan region of Guatemala. Maize, a plant that uses the C4 photosynthetic pathway, leaves a different carbon (13C) isotopic signal in the soil than the C3 plants of the native forest vegetation. Soil profiles were collected from various landscape features around the Classic Maya site of Aguateca: bajos (or wetlands), control locations (areas not conducive to agriculture), defensible locations (areas within or near defensive walls), rehoyadas (natural karst depressions), and upland locations (level soils from across the rest of the landscape). The samples were tested for various chemical and physical properties, and the bulk soil organic matter and humin fractions were analyzed on a mass spectrometer to determine δ13C values. Graphs of the isotopic values were examined and the bulk and humin δ13C enrichment values for the landscape feature categories were compared statistically using ANOVA methods. We determined that the bulk and humin δ13C values of the Bajo and Rehoyada categories showed significantly greater enrichment than the Control, Defensible, and Upland locations. This enrichment was likely the result of sustained periods of maize cultivation, especially in the Rehoyadas. Surface soil bulk and humin δ13C enrichment values do not show that the Bajo or Rehoyada categories are influenced by modern C4 vegetation, nor do the enrichment values of the Control, Defensible or Upland soils. In other words, C3 vegetation dominates each of the landscape features today under natural conditions and probably would have done so anciently absent human interference. (Savanna soils are an exception, but none were identified in the study area.) When the thinner midslope (Backslope) Rehoyada profiles were compared to Control, Defensive, and Upland samples of similar depth, the Backslope Rehoyada profiles had significantly greater bulk δ13C enrichment values that may have resulted from maize cultivation. There was also a significant difference among the surface soil bulk and humin δ13C values of the Backslope Rehoyada, Control, Defensive, and Upland categories, though the reasons are less clear. Both the Bajos and Rehoyadas would have been valuable agricultural resources for maize production for the ancient Maya.

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