Made available in DSpace on 2015-03-26T13:53:19Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1028872 bytes, checksum: d3180d9e4412d72a10b7c398f9549399 (MD5) Previous issue date: 2011-03-25 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / The content of soil organic matter (SOM) is one of the most important indicators of the quality and sustainability of soils. In forestry sector, the management practices are planned so that soil carbon (C) stocks are sustained along rotations. It seems that nitrogen (N) additions in Eucalyptus sp. plantations can accelerate the litter and labile organic matter decomposition at initial stages, but it may contribute to residue C stabilization in more recalcitrant fractions of SOM. This study aimed at quantifying under field conditions: 1) the effect of the N rate on the decomposition of eucalypt harvest residues; 2) the C dynamic into particulate organic matter (POM) and mineral associated organic matter (MAM); and 3) to determine the transfer of fertilizer nitrogen-15 to POM and MAM. The experiment was conducted on short-rotation eucalypt areas in two regions (South and West) with distintic precipitation and clay content, near Eunápolis, in Southern Bahia. The treatments consisted of four levels of N (0, 25, 50 e 100 kg ha-1), five sampling periods (0, 3, 6, 12 and 36 months) all without harvest residue removal and an additional treatment without N addition and harvest residue. Ammonium nitrate was the source of N, except at the 50 kg ha-1 at which 5 % of dose was applied as 15(NH4)2SO4 (98 atom % excess 15N). The experiment was in a randomized block design, with five replicates. Soil samples were collected at depths of 0-10, 10-20, 20-40, 40-60 cm. The application of 50 kg ha-1 of N in the South region reduced the decomposition rate of branches, bark and the combined residues (leaves + branch + bark). Branches and bark showed the higher N half-life time (t0,5). When aboveground plant residues were removed and the roots were the sole C input there was a 33 and 14 % decrease on the more stable MAM-C stocks, respectively, at the South and West regions. In South region N addition preserved more C derived from C4 plants that used to be planted in the area before the eucalypt. After three years of N additions, more fertilizer 15N was in the MAM fraction and less 15N was detected below the 10 cm depth. / Um dos principais indicadores da qualidade e da sustentabilidade dos solos é seu conteúdo de matéria orgânica (MOS). No setor florestal, as práticas silviculturais buscam a manutenção e o aumento do estoque de carbono (C) no solo. Acredita-se que a adição de nitrogênio (N) em plantios de eucalipto pode acelerar a decomposição da serapilheira e da matéria orgânica lábil nos estádios iniciais de decomposição, mas por outro lado, contribui para a estabilização do C do resíduo em frações mais estáveis da MOS. Este trabalho teve como objetivo quantificar, em condições de campo: 1) o efeito de doses de N nas taxas de decomposição do resíduo da colheita de eucalipto; 2) a transferência do seu C para a matéria orgânica particulada (MOP) e associada aos minerais (MAM); e 3) determinar a transferência do N do fertilizante para a MOP e MAM. O experimento foi conduzido em plantios comerciais de eucalipto em duas regiões com precipitações e teores de argila distintos, no município de Eunápolis, Extremo Sul da Bahia. Os tratamentos consistiram de quatro doses de N (0, 25, 50 e 100 kg ha-1), cinco épocas de coleta (0, 3, 6, 12, 36 meses), todos sem a remoção do resíduo, além de um tratamento adicional sem a adição de N e com remoção do resíduo. A fonte de N utilizada foi o nitrato de amônio (NH4NO3), com exceção da dose de 50 kg ha-1, em que 5 % da dose de N foram aplicados como 15(NH4)2SO4, com 98% átomos em excesso. O delineamento utilizado foi em blocos casualizados, com cinco repetições. As amostras de solo foram coletadas nas camadas de 0-10, 10-20, 20-40, 40-60 cm. A dose de 50 kg ha-1, na região sul, reduziu a taxa de decomposição do galho, casca, e do combinado (folha+galho+casca). Os galhos e cascas foram os componentes que apresentam os maiores tempos de meia vida (t0,5) de N. A remoção dos resíduos, com aporte de C apenas via sistema radicular, acarretou em decréscimos de 33 e 14 % no C da frações mais estáveis da MOS, da região Sul e Oeste, respectivamente. Na região Sul, a adição de N preservou o estoque de C originário de plantas C4 cultivadas previamente ao eucalipto na MAM. Após três anos da aplicação de N no solo, a maior porcentagem de 15N encontrava-se na MAM, com pouco 15N sendo perdido para camadas abaixo de 10 cm de profundidade.

SOUSA, Robson Alexsandro de. Desenvolvimento do sorgo CV. BRS Ponta Negra irrigado com água salobra e submetido a diferentes doses de esterco bovino e biofertilizantes. 2015. 171 f. : Tese (doutorado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia Agrícola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2015. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-08-08T13:57:27Z No. of bitstreams: 1 2015_tese_rasousa.pdf: 2067127 bytes, checksum: 3fcff5c579666b463df7111cb934ce87 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-08-08T13:58:47Z (GMT) No. of bitstreams: 1 2015_tese_rasousa.pdf: 2067127 bytes, checksum: 3fcff5c579666b463df7111cb934ce87 (MD5) / Made available in DSpace on 2016-08-08T13:58:47Z (GMT). No. of bitstreams: 1 2015_tese_rasousa.pdf: 2067127 bytes, checksum: 3fcff5c579666b463df7111cb934ce87 (MD5) Previous issue date: 2015 / This study aimed to evaluate the effects of salinity of irrigation water and organic compound on the development in sorghum [Sorghum bicolor (L.) Moench.] cv. BRS Ponta Negra. Therefore, three experiments were performed: the first, there was the effect of cattle manure and commercial biofertilizer Ative® and irrigation with different salinity water in the sorghum plants; in the second there was the cattle manure doses (10, 20, 30 and 40 t ha-1) and the salinity of the irrigation water; and in the third, there was the use of liquid biofertilizer Ative® doses (75, 150, 225 and 300 L ha-1 ) and salinity irrigation water. The plants were grown in pots containing 23 kg of sandy soil under greenhouse conditions. Salinity levels were 0.2; 2.0; 4.0; and 6.0 dS m-1, being used for its preparation is pond water with NaCl added in the first experiment; the second and third experiments with NaCl salts, CaCl22H2O and MgCl26H2O , the ratio of 7:2:1. The experimental design was completely randomized with five replicates in a factorial 4 x 3 in the first experiment; four replications, in a factorial 4 x 4, second and third experiments. The following variables were assessed: total dry matter; culms + sheath diameter; plant height; total leaf area; leaf succulence; bulk density leaf; sodium, potassium, chloride, calcium, magnesium and phosphorus in the leaves and culms + sheath of plants; proline and carbohydrates in the leaves of plants. In addition to the soil analysis of the experiments. The results show the three experiments that salinity affected all variables, with beneficial cattle manure and biofertilizer, however, without reducing the deleterious effects of salts when applied through irrigation water. / Este trabalho teve como objetivo avaliar os efeitos da salinidade da água de irrigação e compostos orgânicos, sobre o desenvolvimento de plantas de sorgo [Sorghum bicolor (L.) Moench.] cv. BRS Ponta Negra. Para isso foram realizados três experimentos: no primeiro, verificou-se o efeito da aplicação de esterco bovino e do biofertilizante comercial Ative® e irrigação com água de salinidades diferentes nas plantas de sorgo; no segundo, verificou-se as doses de esterco bovino (10, 20, 30 e 40 t ha-1) e a salinidade da água de irrigação; e, no terceiro, verificou-se o uso de doses de biofertilizante líquido Ative® (75, 150, 225 e 300 L ha-1) e salinidade da água de irrigação. As plantas foram cultivadas em vasos contendo 23 kg de solo arenoso, em casa de vegetação. Os níveis de salinidade foram 0,2; 2,0; 4,0; e 6,0 dS m-1, sendo que para a sua confecção utilizou-se água de açude adicionada com NaCl no primeiro experimento; no segundo e terceiro experimentos com sais de NaCl, CaCl22H2O e MgCl26H2O, na proporção de 7:2:1. O delineamento experimental foi inteiramente casualizado com cinco repetições em esquema fatorial 4 x 3, no primeiro experimento; quatro repetições, em esquema fatorial 4 x 4, no segundo e terceiro experimentos. Foram avaliadas as seguintes variáveis: matéria seca total; diâmetro do colmo; altura de plantas; área foliar total; suculência foliar; massa específica foliar; teores de sódio, potássio, cloro, cálcio, magnésio e fósforo no colmo + bainhas e limbos foliares das plantas; teores de prolina e carboidratos nas folhas de sorgo. Além das análises de solo dos experimentos. Os resultados evidenciam nos três experimentos que a salinidade influenciou todas as variáveis analisadas, apresentando efeitos benéficos do esterco bovino e biofertilizante, no entanto, sem diminuir os efeitos deletérios dos sais quando aplicados através da água de irrigação.

A estabilização de solos é uma técnica através da qual se busca a melhoria das características de comportamento do solo, especialmente em termos de resistência, deformabilidade, durabilidade e permeabilidade (Ingles & Metcalf, 1972). A ágil e rápida determinação do ganho de resistência de solos artificialmente cimentados ainda não é precisa, e necessita de grande aprimoramento. Com esse objetivo se desenvolveu um equipamento para previsão da resistência de solos moles orgânicos artificialmente cimentados que oferece rapidez nos ensaios e precisão nos resultados. O equipamento basicamente funciona com a cravação de uma haste com base circular alargada adaptada em um anel dinamométrico de nylon que penetra no solo e cujos resultados têm relação linear com a resistência à tração por compressão diametral e resistência à compressão simples independente do tipo de solo, adição de agente cimentante, tipo de agente cimentante, teor de umidade da mistura e tempo de cura. Neste estudo também são mostrados resultados do melhoramento de solo com diferentes teores de cimento e cal, bem como os efeitos dos teores de turfa e resíduo de folhas de eucalipto moídas. Além disso, são avaliados os efeitos do pH baixo através da acidificação das amostras com ácido clorídrico e sulfúrico. O teor de umidade do solo apresenta grande influência nos resultados, pois quanto maior a umidade menor a resistência ou maior o consumo de cimento. A adição de ácido húmico em teores de 0,5%, 2,1% e 4,0% apresentou redução de resistência à compressão simples. As misturas com resíduo de folha de eucalipto moídas e turfa apresentaram redução de resistência e também retardo na atuação dos agentes cimentantes. As misturas com adições de cimento atingiram de uma forma geral resultados superiores comparados com adições de cal virgem. No entanto a combinação de cimento e cal virgem apresentou ótimo desempenho até mesmo superior às misturas com adição de cimento. / Soil stabilization is a technique which seeks to improve the performance characteristics of the soil, especially in terms of strength, deformability, durability and permeability (Ingles & Metcalf, 1972). The agile and rapid determination of the resistance gain of artificially cemented soils is still not accurate and needs major improvement. The main objective of present research was the development and testing, as well as the correlation with standard equipments results, of an apparatus for predicting the resistance of artificially cemented organic soft soils in a fast and accurate testing procedure. The equipment developed in present research basically works with the penetration of a rod with a circular base (adapted in the tip of a dynamometer ring made of nylon) into cement treated soft soils whose results have linear relationship with the tensile strength and compression strength regardless of soil type, addition of cementing agent, type of cementing agent, moisture content of the mixture and curing time. In this study are also shown results of soil improvement due to insertion of different amounts of cement and/or lime, and the effects of the amounts of peat and crushed eucalyptus leaves into soil strength. Furthermore, the effects are evaluated from low pH by acidifying the sample with specific acids. The moisture content of the soil has a major influence on the results, the higher the humidity the lower resistance or higher cement consumption. The addition of humic acid at levels of 0.5%, 2.1% and 4.0% showed a reduction of the compressive strength. Mixtures with waste ground eucalyptus leaf and peat showed a delayed action on cementing agents. Some combinations of cements (cement, lime and ash) showed excellent performance. Combinations of cements generally obtained higher results compared to lime addition. However combinations of cement and lime came up with results better than mixtures with only cement.

O plantio direto (PD), associado a plantas de cobertura, pode melhorar os atributos químicos e a qualidade do solo, dependendo do tipo de solo. O objetivo da pesquisa foi avaliar o impacto do PD, associado a diferentes sistemas de cultura, durante longo período (~30 anos) sobre os atributos químicos e indicadores de qualidade de um solo de clima subtropical e de um solo de clima temperado (Estudos I e II), e da influência de sistemas de cultura sobre a eficiência da calagem superficial em PD em um solo de clima subtropical (Estudo III). Nos estudos I e II foram avaliados experimentos instalados em 1985 em Eldorado do Sul (Brasil) e em Concord (EUA) cultivados em PD e preparo convencional (PC). No experimento em Eldorado do Sul foram utilizados três sistemas de cultura: aveia (Avena strigosa)/milho (Zea mays) (A/M), ervilhaca (Vicia sativa)/milho (V/M) e aveia+ervilhaca/ milho+caupi (Vigna unguiculata) (AV/MC), em duas doses de N (0 e 180 kg ha-1). O experimento em Concord foi conduzido com dois sistemas de cultura: milho contínuo e milho-soja (Glycine max)], em três doses de N (0, 80 e 160 kg ha-1). O Estudo III foi conduzido em um experimento instalado em 1983 em PD, sendo avaliados atributos químicos relacionados à acidez do solo antes e dois anos após a calagem (5,0 Mg ha-1) em cinco sistemas de cultura: pousio/M (P/M), A/M, AV/M, AV/MC, LL (Lablab purpureus)+M (LLM), com e sem calagem e em duas doses de N (0 e 180 kg ha-1). As práticas de manejo de longa duração influenciaram os atributos químicos do solo, principalmente, na camada de 0 a 10 cm de profundidade, na qual o PD aumentou, em média, 23 % o teor de C orgânico do solo (COS), 30 % o teor de nitrogênio total (NT) e 100 % o teor de P disponível, em relação ao PC, nos dois solos. O COS e o NT aumentaram na ordem A/M<V/M<AV/MC, enquanto que, o pH, o P disponível e a saturação por bases reduziram na ordem A/M>V/M>AV/MC. O COS e o NT não foram influenciados, mas o pH e a saturação por bases aumentaram na rotação milho-soja. O COS aumentou 5% na dose de 160 kg N ha-1 no solo temperado. A adubação nitrogenada reduziu o pH e a saturação por bases nos dois solos, contudo reduziu 30 % o P disponível no solo subtropical, mas aumentou 20 % no solo temperado. O PD aumentou o estoque e o índice de estratificação (IE) do COS e do C orgânico particulado (COP) e o índice de labilidade (IL) nos dois solos. A inclusão de leguminosas aumentou o IE do COS e COP, e o IL em PD. Os sistemas com leguminosas de cobertura de solo aumentaram a acidificação e a saturação por Al3+ e reduziram a saturação por bases, comparado com sistemas exclusivamente de gramíneas. Após dois anos da calagem superficial o pH foi maior que 5,0 e a saturação por Al3+ foi < 4,0 % até 5 cm, independente do sistemas de cultura, porém, a saturação por bases aumentou para > 50 % até 7,5.cm. As práticas de manejo apresentam comportamento similar entre os diferentes solos, e os sistemas de culturas não influenciaram na eficiência da calagem na camada superficial do solo. / No-till (NT), associated with cover crops, can improve soil chemical properties and quality, which the magnitude of the effects possibly is dependent of soil type. The objective of this research was to evaluate the impact of NT, associated with different cropping systems, cultivated for long-term (~ 30 years) on soil chemical properties and quality indicators of subtropical soil in Southern Brazil and a temperate soil in Midwest US (Studies I and II), and cropping systems influence on liming efficiency in a subtropical soil under long-term NT (Study III). In Studies I and II were used two long-term experiments installed in 1985 in Eldorado do Sul (Brazil) and Concord (US) carried out under NT and conventional tillage (CT). In Brazil, the experiment was composed by three cropping systems: oat (Avena strigosa) / corn (Zea mays) (O/C), vetch (Vicia sativa)/corn (V/C) and oat+vetch/corn+cowpea (Vigna unguiculata) (OV/CC), with two N rates (0 and 180 kg ha-1). In US, the experiment was conducted with two crop rotations: continuous corn and corn-soybean (Glycine max), with three N rates (0, 80 and 160 kg ha-1). The Study III was conducted in a third experiment under NT and assessed soil chemical attributes related to acidity, before and two years after liming (5.0 Mg ha-1), in five cropping systems: fallow/C (F/C), O/C, OV/C,OV/CC, LL (Lablab purpureus)+C LLM), with and without liming and two N rates (0 and 180 kg ha-1). The long-term management effects on soil chemical properties were confined from 0 to 10 cm depth, in which NT system increased, in average, 23 % of soil organic C (SOC), 30 % of total N (TN), 100 % of available P, compared with CT in subtropical and temperate soil. Subtropical cropping systems increased SOC and TN in the order O/C<V/C<OV/CC, while soil pH, available P and base saturation decreased in the order O/C<V/C<OV/CC. Temperate crop rotation had no effects on SOC and TN, but soil pH and base saturation increased in corn-soybean rotation. Nitrogen fertilization increased 5 % of SOC in the N rate of 160 kg ha-1 in temperate soil. Nitrogen fertilization decreased soil pH and base saturation in both soils, but decreased 30% available P in subtropical soil, but increased 20% in temperate soil. No-till increased SOC and particulate organic C (POC) stocks, SOC and POC stratification ratio (SR) and lability index (LI) in both soils. Legume-based cropping systems increased the SOC and POC SR and LI under NT. Besides, legume-based cropping systems increased soil acidification and Al3+ saturation, and decreased base saturation, compared with grass crops. After two years of superficial liming, soil pH increased to >5.0 and Al3+ saturation decreased to <4.0% up to 5 cm, regardless of cropping systems, and base saturation increased to >50% up to 7.5 cm depth. Long-term management practices have similar behavior in the subtropical and temperate soil, and cropping systems has no influence on liming efficiency in topsoil.

Nas mais diversas atividades industriais hoje existentes está presente a problemática dos resíduos gerados e seu gerenciamento. Os efluentes líquidos são uma grande fonte de poluição dos recursos hídricos, sendo necessário o controle das condições de seu descarte. Para efluentes contendo poluentes orgânicos uma das alternativas de tratamento que vem sendo muito utilizada é o uso de Processos Oxidativos Avançados - POA’s. Esses processos se baseiam na geração de radicais livres, principalmente o radical hidroxila (HO.), que possui alto poder oxidante e pode promover a degradação de vários compostos poluentes eficientemente. Esses processos têm obtido grande atenção devido ao aumento da complexidade e dificuldade no tratamento de águas residuárias, o que tem sido motivo para a busca de novas metodologias visando a remediação desses rejeitos. Diante disso, o presente trabalho tem por objetivo estudar os processos (POA’s), para a degradação da matéria orgânica em efluente oriundo da descontaminação de madeira tratada com Arseniato de Cobre Cromatado – CCA. Este efluente é gerado através de extração ácida em ciclos de madeira tratada com CCA que foram utilizados como postes tanto de eletricidade como de telefonia. O efluente gerado na extração ácida foi caracterizado através dos parâmetros de pH, Condutividade, Demanda Química de Oxigênio, Carbono Orgânico Dissolvido, Sólidos totais e metais. Após caracterização, o efluente foi submetido aos processos oxidativos avançados de Fotólise, Fotocatálise heterogênea, Eletrólise e Fotoeletrooxidação, a fim de degradar a matéria orgânica. Depois de realizados os processos, o efluente foi caracterizado novamente com os mesmos parâmetros. Pode-se concluir que todos os processos utilizados alcançaram resultados positivos, degradaram a matéria orgânica, mas o processo que obteve melhor rendimento de degradação foi o de Eletrólise que degradou 68% da matéria orgânica presente no efluente. / In the most diverse industrial activities exist today is present the problem of waste generated and its management. Liquid effluents are a major source of pollution of water resources, requiring the control of the disposal conditions. For wastewater containing organic pollutants the use of Advanced Oxidation Processes - POA's has been widely used. These processes are based on the generation of free radicals, especially the hydroxyl radical (HO.), which has high oxidizing power and can promote the degradation of several polluting compounds efficiently. These processes have achieved great attention due to the increasing complexity and difficulty in the treatment of residual waters, which has been the reason for the search of new methods for remediation of these wastes. Therefore, this paper aims to study these processes (POA's) for the degradation of organic matter in the effluent coming from the decontamination of wood treated with CCA - chromated copper arsenate. This effluent is generated by cycles of acid extraction of wood treated with CCA which were used as both telephone and electricity poles. The effluent generated by the acid extraction was characterized by the parameters pH, conductivity, chemical oxygen demand, dissolved organic carbon and metals. After characterization, the effluent was subjected to advanced oxidation processes photolysis, heterogeneous photocatalysis, Electrolysis and photoelectrooxidation (which are the three processes together) in order to degrade organic matter. After the effluent treatment, the solution was again characterized by the same parameters. It can be concluded that all the processes used have achieved positive results, degradeding organic matter, but the process that showed the best performance degradation was the electrolysis with 68% less organic matter.

Due to the high specific surface area and aspect ratio (length to diameter ratio, or L/D) of carbon nanotubes, they tend to bind strongly through the van der Waals interactions prevailing among tubes. Thus, they agglomerate and settle in water to form large conglomerates. The adsorption of natural organic matter (NOM) or surfactants onto raw multi-walled carbon nanotubes (MWCNTs) was shown to effectively enhance the dispersibility and stabilization of MWCNTs. The two kinds of dispersants used were humic acid and peptone. Also, two functionalized MWCNTs (-OH and -COOH functional groups) were also dispersed in humic acid (HA) to evaluate the effect of surface property on CNT biological interactions. Based on the dynamic light scattering (DLS) analyses, the use of surfactants increased the steric hindrance as well as the charge repulsion between adjacent CNT particles, thereby enhancing their suspension. HA and peptone sorption onto the surface of MWCNTs can cover their hydrophobic surfaces and help stabilize CNTs. Furthermore, hydroxyl modification of MWCNTs resulted in stable dispersions in water containing HA at 10 and 1000mg/L, while COOH-MWCNT suspensions displayed stable dispersion with lower negative surface charges solely at 100g/L. While, TEM images agreed with the DSL analysis that HA-stabilized MWCNTs were well-dispersed compared to pep-stabilized MWCNTs. Both f-MWCNT types showed a significant reduction in agglomerates as compared to the non-functionalized one. It was noted that the dispersion state as well as the surface properties of both MWCNTs and f-MWCNTs plays an effective role in the potential toxic effects of CNTs. Decreases in the growth rate, chlorophyll index, water uptake, dry weight, and root elongation rate along with a rise in mortality were detected as an indication of phyto-toxicity in both the pep-MWCNT suspensions at 1000mg/L and the peptone control seedlings in contrast to the seedlings treated with pep-MWCNTs at 10 and 100mg/L doses . This was an indicator for the presence of suspended MWCNTs as well as their unstable dispersion in the water column. However, the interaction between the HA-CNTs and the plants improved development in terms of water uptake, growth rate, chlorophyll index, dry weight and root elongation rate due to their well- dispersed stability in water. There were no differences among the f-MWCNT, MWCNT and HA plant groups in terms of their quantum yield and chlorophyll content. While the f-MWCNTs significantly enhanced the plants' growth, water transpiration, and dry root and shoot weight as compared to the non-functionalized MWCNTs. It appeared that exposure to OH-MWCNTs improved the development of tomatoes in terms of water uptake, root elongation rate, and growth rate as well as light- and dark-adaptation, whereas COOH-MWCNTs and non-functionalized MWCNTs were apparently toxic in terms of root leakage and dark-adaptation. Overall, our results suggest that the surface properties of CNTs associated with their dispersion stability specify their influence on the growth of tomato plants. Moreover, the nature of the dispersant agent itself plays an active role in the toxicity of MWCNTs on tomatoes. Our investigation indicated that there is a significant correlation between the toxicity of unfunctionalized MWCNTs and f-MWCNTs and the toxicity of the dispersant agent.

Igneous intrusion can change the geochemical and petrographic properties of sedimentary organic matter (such as coals and organic-rich clays or shales) including vitrinite reflectance, maceral petrographic composition, mineralogy, stable isotope composition, trace element composition, and bulk geochemistry. Igneous intrusions into coals and organic-rich rocks may have contributed to global warming in the geologic past by causing the release of greenhouse gases. Evidence for the release of large amounts of thermogenic CH4 from the organics would include significant;13Corg enrichment in the residual organic matter. However, 13Corg of thermally altered organic matter in coals and shales adjacent to intrusions often show negative shifts and, in some cases, ambiguous or positive trends. Previous studies have evaluated 13Corg of bulk samples rather than that of individual components, or macerals. As different macerals have different isotopic compositions, maceral-specific trends may be masked by variations in maceral composition of the whole-coal samples. It is important to explain the evolution of different geochemical and petrographic signatures in coals, coals macerals, and organic-rich sedimentary rocks close to an intrusion. This study evaluates the following three hypotheses: (1) thermally altered coals show different geochemical trends compared with coals that have undergone normal burial maturation; (2) if a large-scale release of 13C-depleted thermogenic CH4 resulted from intrusion of the coal, then it should have produced 13C-enriched coal and vitrinite macerals (the most abundant components of the coal) adjacent to the intrusion due to the release of light gases; and (3) 13Corg gets heavier with the increase in heat alteration approaching an intrusion due to the release of isotopically light gases. The current study reports petrographic, bulk geochemical (proximate, and ultimate), 13Corg data (whole-coal/shale samples and vitrinite macerals separated via density-gradient centrifugation, (DGC)), density data (vitrinite macerals), and Rock-Eval pyrolysis data for occurrences of thermally altered Springfield (No. 5) Coal (Pennsylvanian), Danville (No. 7) Coal (Pennsylvanian), and an organic-rich shale in the southern part of the Illinois Basin. Petrographic analysis shows an increase in vitrinite reflectance (Rm) from background levels of 0.55% up to ~4.80% in the Springfield (No. 5) Coal, 0.66% to 4.40% in the Danville (No. 7) Coal, and 0.71% to 4.78% for organic-rich shale; a loss of liptinite macerals, formation of isotropic coke and, at the intrusion contact, even development of fine-grained mosaic anisotropic coke texture. Volatile matter (VM) content decreases and fixed carbon (FC) content, ash, and mineral matter increase approaching the coal/intrusion contact. Carbon increases whereas nitrogen, hydrogen, and oxygen decrease approaching the intrusions. The presence of carbonate minerals (confirmed by X-ray diffraction and petrographic analysis) has a significant impact on proximate and ultimate data. However, even after removal of carbonates, trends for VM vs. vitrinite reflectance, %C vs. Rm, and H vs. C do not follow typical trends associated with normal burial coalification. Approaching the contacts, free oil content (S1), remaining hydrocarbon potential (S2), carbon dioxide from pyrolysis of the organic matter (S3), and hydrogen (HI) and oxygen (OI) indices decrease whereas thermal maturity (Tmax, ⁰C) increases. In addition, HI vs. VM, S2 vs. Rm, and Tmax vs. Rm diverge from pathways seen in previous studies. Trends in most of the Rock-Eval parameters in the organic-rich shale studied here are less clear due to the degree of variation in organic matter content, but a clear increase in thermal maturity (Tmax, C) is seen. There are no significant changes in 13Corg in the whole-coal samples (WCM) of the Springfield (No. 5) Coal (-25.28 / to -24.88 /), Danville (No. 7) whole coals (-25.37 / to -24.76 /), and in the DGC-separated vitrinites (-25.33 / to -24.96 /) of the Springfield (No. 5) Coal approaching the intrusion. However, the organic-rich shale transect shows a 1.31 / positive shift in 13C (from -25.06 / to -23.87 /) approaching the intrusion. DGC-separated vitrinite densities range from 1.268 g/mL in the unaltered coal to 1.523 g/mL at the coal/intrusion contact. For the vitrinite concentrates, density shows a clear correlation with Rm, %Cdaf, Hdaf, H/C, TOC, and 13Corg. These geochemical data suggest that these coals may have followed a different maturation track because of the geologically rapid heating associated with the intrusive event. It is also suggested here that the natural coke textures produced by such rapid geological heating may differ from those observed for metallurgical cokes produced under standard industrial coking conditions. Typically, in an industrial coke oven, a coal of this initial rank (Ro = ~ 0.6%) would produce an isotropic coke, rather than the fine-grained circular anisotropic coke seen here. The development of this texture may reflect differences due to heating rates or, alternatively, may indicate "pre-heating" of the coal during the intrusion event. Changes in the isotopic signatures are not of a magnitude that would be expected if significant thermogenic CH4 had been generated by the intrusive event. Moreover, there is no petrographic evidence for condensed or immobilized thermal products due to rapid pyrolysis (12C-rich pyrolytic carbon) close to the intrusion. These geochemical and petrographic data suggest there was only minimal CH4 generation associated with the rapid heating of the coals and organic-rich sedimentary rocks by the intrusion. In addition, there is no evidence for 13C-depleted condensed gas or pyrolytic carbon at the intrusion contact that could have moderated the isotopic signature. These data agree with previously reported data from this laboratory (Rahman et al., 2014, in review) and others (Gröcke et al., 2009; Yoksoulian, 2010) that indicate no clear evidence for large-scale CH4 generation due to the rapid heating or igneous intrusion in coals or sedimentary rocks.

Soil organic matter (SOM) decomposition and formation is an important climate feedback, with the potential to amplify or offset climate forcing. To understand the fate of soil carbon (C) stores and fluxes (i.e., soil respiration) under future climate it is necessary to investigate responses across spatial and temporal scales, from the ecosystem to the molecular level, from diurnal to decadal trends. Moreover, it is important to question the assumptions and paradigms that underlie apparently paradoxical evidence to reveal the true nature of soil-climate feedbacks. My dissertation includes research into the response of soil respiration in Pacific Northwest prairies to warming and wetting along a natural regional climate gradient (Chapter II), and then delves deeper into the mechanisms underlying SOM decomposition and formation, examining the temperature sensitivity of SOM decomposition of prairie soils that were experimentally warmed for ~2 yr, and a forest soil in which litter-inputs were manipulation for 20 yr (Chapter III), and finally testing soil C cycling dynamics, including mineral-associated C pools, decomposition dynamics, and the molecular nature of SOM itself, under litter-manipulation in order to understand the controls on SOM formation and mineralization (Chapter IV). This dissertation includes previously published and unpublished coauthored material; see the individual chapters for a list of co-authors, and description of contributions.

A Bacia do Araripe, conforme Brito Neves et al. (2000), está inserida na unidade geotectônica da Província Borborema, abrangendo os estados do Ceará, Pernambuco e Piauí. Este trabalho buscou identificar possíveis intervalos potencialmente geradores da Formação Santana (Aptiano-Albiano) na Bacia do Araripe, a partir de técnicas de geoquímica e petrografia orgânica para caracterizar dez amostras de campo, referentes a folhelhos orgânicos provenientes deste intervalo estratigráfico. Os valores de COT indicam que todas as amostras possuem mais que o mínimo de carbono orgânico necessário para geração de hidrocarbonetos, a partir de 1 % em massa. Foram encontrados valores no pico S2 que variam de 7,44 a 13,56 mg HC/g de rocha para os Membros Crato e Romualdo (base e topo da Formação estudada), conferindo-lhes um potencial petrolífero bom e muito bom, respectivamente. No Membro intermediário, Ipubi, há um acréscimo na produção de hidrocarbonetos rumo ao seu topo estratigráfico, mas ocorre também a amostra com mais pobre potencial petrolífero, a amostra 9, com valor de S2 de 0,05 mg HC/g de rocha. O tipo de querogênio é classificado como tipo II para os Membros Crato e Romualdo, e tipos I, II e III para o Membro Ipubi. Os valores de ICE variam entre 3.0 a 4.0 (Robertson Research Limited), e de Tmax (361 a 433 ºC), permitindo classificar as amostras como imaturas a marginalmente maturas, conforme classificação de Peters & Cassa (1994) Foram encontradas vitrinitas apenas no Membro Ipubi, indicando material imaturo com 0,29 – 0,48% Rrandom, e baixo grau de maturação 0,60% Rrandom na amostra 2. A petrografia sob luz refletida mostra que as amostras 2, 3 e 9 estão contaminadas por betumen, interferindo nos valores de índice de produção, além de reflectância da vitrinita para a amostra 9. Análises de DRX mostram que o quartzo é o mineral mais abundante nas amostras, seguido pela esmectita e calcita, por vezes gipso, pirita e ilita e raramente caolinita. A petrografia sob luz transmitida, indica a matéria orgânica amorfa, como sendo o principal componente do querogênio estudado, seguido por fitoclastos e palinomorfos. A Análise elementar das razões atômicas de N, C, H e S, apontam os maiores valores nas amostras 5 a 8 (Membro Ipubi), podendo relacioná-las também aos maiores valores de COT e pertencentes a querogênio do tipo I, o menor valor dos parâmetros supracitados ocorre na amostra 9, a única que possui querogênio do tipo III. Os valores intermediários encontrados nas amostras 1 a 4 e 10, coincidem com amostras referentes a querogênio do tipo II. O intervalo em que se observa maior predominância destas condições está localizado no topo do Membro Ipubi, englobando as amostras 5 a 8. Foi determinado, a partir das análises realizadas, que este grande intervalo é caracterizado como o maior potencial gerador de petróleo identificado neste trabalho, apesar das amostras analisadas estarem imaturas. / The Araripe Basin, according to Brito Neves et al. (2000), is inserted in the geotectonic unit of the Borborema Province, covering the states of Ceará, Pernambuco and Piauí. This study aimed to identify possible potentially generating intervals of the Santana Formation (Aptian-Albian) in the Araripe Basin, from geochemical techniques and organic petrography to characterize ten samples field, referring to organic shales from this stratigraphic interval. The COT values indicate that all samples have more than the minimum of organic carbon required for generation of hydrocarbons, from 1% by mass. The S2 values ranging from 7.44 to 13.56 mg HC / g of rock for the Crato and Romualdo Members (base and top of the study Formation), giving them a good petroleum potential and very good, respectively. In the intermediate member, Ipubi, there is an increase in production of hydrocarbons toward its top stratigraphic, but also occurs the sample with poorer oil potential, the sample 9, with a value of S2 0.05 mg HC / g rock. The type of kerogen is classified as type II for Members Crato and Romualdo, and types I, II and III to the Member Ipubi. SCI values range from 3.0 to 4.0 (Robertson Research Limited), and Tmax (361-433 °C), allowing classifying the samples as immature to marginally mature, as Peters & Cassa classification (1994). Vitrinitas were found only in the Member Ipubi indicating immature material with from 0.29 to 0.48% Rrandom and low degree maturity 0.60% Rrandom the sample 2 The petrographic under reflected light shows that samples 2, 3 and 9 are contaminated with bitumen, interfering with the production index values, and the vitrinite reflectance for sample 9. XRD analysis shows that quartz is the most abundant mineral in the samples, followed by the smectite and calcite sometimes gypsum, pyrite and illite and kaolinite rarely.The petrographic under transmitted light, indicates the amorphous organic material as the main component of kerogen studied, followed by phytoclasts and palinomorphs. The Analysis of the atomic ratios of N, C, H and S, indicate the highest values in samples 5-8 (Member Ipubi), associated also to higher TOC values and belonging to Type I kerogen, the lowest value the above parameters occurs in the sample 9, the one that has the type III kerogen. Intermediate values found in samples 1 to 4 and 10 matching samples related to type II kerogen. The interval in which there is a predominance of these conditions is located at the top of the Member Ipubi, encompassing the samples 5 to 8. It was determined from the analyzes carried out, this long interval is characterized as the greatest potential for generating oil identified in this work although of the samples are immature.

The aim of the theses was to describe soil organic matter changes in model landscape Stropnice subcatchments that have different biotopes and agricultural and forest management.Particular aims were: 1) to determine the link between landuse, soil environment changes and catchment matter losses. 2)to experimentally prove the water regime impact on carbon and other substances losses during and between vegetation seasons.