This dissertation aims primarily at determining the energy yield that can be produced, if certain species of energy crops are grown (under various regimes of fertilizing and sowing) by the Faculty of Agriculture, the University of South Bohemia, on a university's trial parcel. Zea mays L. is one of the energy crops chosen for the experiment; it is grown on a large area in the Czech Republic nowadays. Perennial crops of Phalaris arundinacea L., Elymus elongatus subsp. ponticus cv. Szarvasi-1 andMiscanthus × giganteus were also chosen for this experiment. Based on the collected data, a risk of erosion provoked by the above-mentioned crops has been determined by using USLE method. The crop stands and the soil have been analysed too. This analysis has focused on the organic matter evaluation, by using a brand new method. Last but not least, occurrence of Carabidae beetles has been studied and evaluated within the research; they are considered bio indicators of the environmental conditions. Our experiment has shown that Zea mays L. is the most high-yielding species. On the other hand, Phalaris arundinacea L. has not produced positive results; the most high-yielding variation of it only made a half yield of Zea mays L. In contrast to Zea mays L., grass species of Phalaris arundinacea L. andElymus elongatus have had an extraordinary anti-erosion capacity. Studying the amount of primary organic matter in the soil, we have found almost double amount of it in Miscanthus × giganteus andZea mays L. crop stands, compared to another two species. Monitoring oxidation reaction kinetics of the primary organic matter, we could count the oxidation speed constant of k. There have been dramatic differences between the individual soil samples. However, the data file is too complicated to draw the general conclusion from. On the other hand, evaluating the data gathered by studying Carabidae beetles and the environmental values of the crops stands, we have found out the crop stands are not too valuable from the environmental point of view. We have found out the perennial species have got an extraordinary anti-erosion capacity. We recommend Miscanthus × giganteus and Elymus elongatus, in particular, as an alternative to corn, especially to regions highly endangered by erosion.

Master of Science / Department of Agronomy / Antonio R. Asebedo / Johanna A. Dille / Field experiments were conducted in 2016 and 2017 across nine locations in Kansas to develop and evaluate a procedure for variable-rate applications (VRA) of soil-applied herbicides in corn and grain sorghum based on soil properties. Soil electrical conductivity (EC) and soil organic matter (SOM) data were collected at each location using a Veris MSP3. Soil EC was correlated to soil texture and herbicide algorithms were developed for two different tank-mixes for corn and for grain sorghum. Three algorithms were evaluated in the field for each tank-mix based only on SOM (alg-SOM), SOM and soil texture (alg-SOMtex), or a flat rate based on the average soil properties for the entire field. Rates for each tank-mix were based on the maximum usage rate (MUR) allowed. When soil variability across a field was adequate, VRA based on algorithms were effective at five of the nine locations. Across these five locations, alg-SOM resulted in the same or better weed control at 8 weeks after treatment (WAT) compared to the flat rate and reduced herbicide use by 12% for both tank-mixes in grain sorghum. Using alg-SOMtex reduced herbicide use by 24% in grain sorghum, but had less weed control at several locations compared to the flat rate. VRA was practical at Morganville, KS in 2017. Both alg-SOM and alg-SOMtex increased the amount of herbicide applied compared to the flat rate, but alg-SOMtex resulted in greater Palmer amaranth control (92%) compared to the flat rate (71%). Separate greenhouse and field experiments were conducted in 2017 to evaluate the activity of soil-applied herbicides on controlling HPPD-inhibitor resistant Palmer amaranth populations. A dose-response greenhouse experiment of soil-applied mesotrione and isoxaflutole was performed using resistant (Stafford County) and susceptible (Riley County) Palmer amaranth populations. Reduced susceptibility was observed with resistant-to-susceptible ratios being 7.2 for mesotrione and 4.1 for isoxaflutole. Field experiments were conducted at two locations in KS with one field having HPPD-resistant (Barton County) and the other HPPD-susceptible (Reno County) Palmer amaranth populations. Treatments were three HPPD-inhibiting herbicides [mesotrione (¼X, ½X, and 1X = 210 g ha-1), isoxaflutole (½X and 1X = 105 g ha-1), and bicyclopyrone (1X = 50 g ha-1 and 2X in formulated tank-mix with bromoxynil at 700 and 1400 g ha-1)] in comparison to other soil-applied herbicides commonly used for Palmer amaranth control. HPPD-inhibitor treatments were applied alone and tank-mixed with atrazine (2240 g ha-1). Overall, control of Palmer amaranth was reduced for HPPD-resistant compared to -susceptible populations. All treatments of mesotrione and isoxaflutole at 4 WAT resulted in 81 to 99% control in Reno County, but only 55 to 89% control in Barton County. For mesotrione and isoxaflutole treatments across both sites, Palmer amaranth control at 4 WAT was greater when 1X was applied (89%) compared to 0.5X (81%). Tank-mixing atrazine with mesotrione and isoxaflutole increased Palmer amaranth control from 82 to 88%. Soil-applied HPPD-inhibitors were most effective when applied at field usage rate in combination with atrazine for both populations. When using soil-applied HPPD-inhibitors, management recommendations should be the same regardless of Palmer amaranth population.

Submitted by JÉSSYCA DELLINHARES LOPES MARTINS null (dellinhares@hotmail.com) on 2017-04-14T13:16:41Z No. of bitstreams: 1 Tese jessyca.pdf: 2737738 bytes, checksum: 4a9e9501939a9f6435d392bb370132b7 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-18T14:34:35Z (GMT) No. of bitstreams: 1 martins_jdl_dr_bot.pdf: 2737738 bytes, checksum: 4a9e9501939a9f6435d392bb370132b7 (MD5) / Made available in DSpace on 2017-04-18T14:34:35Z (GMT). No. of bitstreams: 1 martins_jdl_dr_bot.pdf: 2737738 bytes, checksum: 4a9e9501939a9f6435d392bb370132b7 (MD5) Previous issue date: 2017-03-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / 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.

The contemporary methods of evaluation of the soil organic matter do not sufficiently characterize its stability. The aim of this study is to develop a method for soil organic matter stability evaluation. The four different methods were tested, two based on chemical principle a two on microbiology principle. The first method is based on sequential soil organic matter fractionation by a system of solvents with increasing polarity, the second method uses oxidizers with different oxidizing efficiency. In the third method micro-organisms decompose soil organic matter in anaerobic environment as well as in the four method, but this one makes use of up gas production measuring sensors. The method of sequential extraction is not suitable for practical use, the oxidation method is preferred. The oxidation method also both microbiology methods imply that the most important part of soil organic matter is decomposed rapidly or while using weak oxidizer. This fraction is the most important for evaluation decomposability and it is characteristic for particular soils. After decomposition of this part of SOM its remnant is decomposed steady and linear or micro-organisms are not able to decompose it.

Made available in DSpace on 2015-04-11T13:54:38Z (GMT). No. of bitstreams: 1 DISSERTACAO_ELISELDA.PDF: 1519616 bytes, checksum: d7a17419f0ab7c2c54e8cb9e0acd7052 (MD5) Previous issue date: 2005-12-20 / Fundação de Amparo à Pesquisa do Estado do Amazonas / The understanding of dynamics of soil and agroforestry systems is the essential part to establish an appropriate handling of nutrients and their sustaining, since that they provide an increasing in environmental works. The purpose of this study was to evaluate the decomposition and availability of nutrients found in the phytomass of Brazilian chestnut trees, as well as cupuaçu Theobroma grandiflorum (a Brazilian plant very closely related to the cacao tree), Gliricidia sepium, and other combinations among them, based on a agroforestry pattern of system, which is nine years old now. This experiment was carried out at Campo Experimental Confiança, in Roraima, between April and September, which is the period of rainy season. The phytomass of the researched species was put in sacks of decomposition with screens made of polyethylene measuring 0,40 x 0,40, and with mesh of one millimeter in thickness. Those materials were spread on the soil surface to be gathered fortnightly over the whole evaluation period. The experimental design was made with randomized blocks with five replicates. After each gathering, the weight difference between the current gathering and the previous one was regarded as decomposition rate. The values obtained were fitted according to a no linear pattern of logistic type, and having the adjusted coefficient of determination (R2 aj) as criterion of adherence. Brazil nut, cupuaçu and gliricidia leaves showed a distruct behavior relahve to time for decomposition, as gliricidia presented rapid decomposition while cupuaçu leaves showed slowest decomposition cnnidering time assessed. There was no influence concerning association of leaves over decomposition time. Gliricidia leaves presentend high nitrogen, potassium, magnesium and phosforus relaease. Brasil nut and cupuaçu leaves shoewd low nutriente release, specialy nitrogen. Calcium was the nutriente that presentend least release for all species under study, requiring a longer time than time utilized in this study fot its complet release. / A compreensão sobre a dinâmica do sistema solo e planta dos sistemas agroflorestais é parte essencial para estabelecer o manejo adequado de nutrientes e a sua sustentabilidade, proporcionando o incremento nos serviços ambientais. O objetivo deste trabalho foi avaliar a decomposição e a liberação de nutrientes das folhas de castanha-do-Brasil (Bertholletia excelsa), cupuaçu (Theobroma grandiflorum) e gliricídia (Gliricidia sepium) e entre as mesmas, em um sistema agroflorestal com nove anos de idade. O estudo foi conduzido no campo experimental Confiança da Embrapa Roraima, de abril a setembro de 2004, que compreende o período chuvoso na região. As folhas das espécies em estudo foram alocadas em sacos de decomposição de tela de polietileno com dimensão de 0,40 x 0,40 m com malha de 1 mm, os quais foram distribuídos na superfície do solo e coletados quinzenalmente durante todo o período de avaliação. O delineamento experimental utilizado foi de blocos casualizados, com três repetições. Após cada coleta, a diferença de peso entre a coleta atual e a anterior foi considerada como taxa de decomposição. Os valores obtidos foram ajustados segundo modelo não linear do tipo logístico, tendo como critério de aderência o coeficiente de determinação ajustado (R2 aj). As folhas da castanha-do-Brasil, do cupuaçu e da gliricídia apresentaram comportamento distintos quanto ao tempo de decomposição, sendo que as folhas da gliricídia apresentaram mais rápida decomposição, enquanto que as folhas de cupuaçu apresentaram mais lenta decomposição no tempo avaliado. Não se observou influência da associação das folhas sobre o tempo de decomposição. As folhas de gliricídia apresentaram alta liberação de nitrogênio, potássio, magnésio, e fósforo. As folhas de castanha-do-Brasil e cupuaçu apresentaram baixa liberação de nutrientes, especialmente nitrogênio. O cálcio foi o nutriente que apresentou a mais lenta liberação para todos as espécies estudadas, requerendo tempo superior aquele empregado neste estudo para a sua completa liberação.

A agricultura pode ser uma aliada importante para a mitigação da concentração de gás carbônico (CO2) na atmosfera. Pela fotossíntese pode-se converter o CO2 da atmosfera em massa vegetal, e, além disso, por meio de um manejo adequado desta massa pode-se reter parte do carbono (C) no solo, caracterizando um \"seqüestro de C\" da atmosfera pelo solo. Pesquisas têm se voltado para entender o papel da produção agrícola, como os sistemas conservacionistas de manejo, ou seja, o plantio direto (PD), e das pastagens de Brachiaria sobre a dinâmica do C no solo. Estudos sobre a dinâmica e a estabilidade da matéria orgânica do solo (MOS) são necessários, já que variáveis como estoques de carbono (EC) e graus de humificação podem ser avaliados, e sendo assim, obter parâmetros fundamentais para a mitigação de CO2 na atmosfera, tema que se insere num dos enfoques das Mudanças Climáticas Globais. Nesse contexto, espectroscopias, como por exemplo, a Ressonância Paramagnética Eletrônica (RPE), a Fluorescência de luz no ultravioleta-visível (UV-vis) e a Fluorescência Induzida por Laser (FIL) podem ser fundamentais na avaliação da estabilidade da MOS. Este trabalho teve como objetivo verificar o comportamento da MOS em áreas com potencial para seqüestro de C, por meio da avaliação dos estoques deste no solo, em diferentes sistemas de manejo e posterior caracterização por Espectroscopia. Além disso, e em função das dificuldades encontradas na seleção da melhor metodologia para a quantificação de C, foi também possível avaliar métodos de determinação de C, comparando-os entre si pelos coeficientes de variação e análise multivariada, e assim propondo uma melhor metodologia. Em área tropical de pastagens de Brachiaria decumbens, no Brasil, os resultados mostraram que a determinação dos EC foram maiores nesses sistemas, comparado com a vegetação nativa de cerradão, após 27 anos de experimento. Os maiores EC obtidos pelas pastagens foram favorecidos pela constante entrada de material vegetal na superfície do solo, também influenciado pela entrada do nitrogênio (N), além do sistema radicular da gramínea, considerando o tratamento de pastagem com adição anual de N e aplicação de 2 t ha-1 de calcário (com reforço de 1 t ha-1 anual), o melhor tratamento em função do acúmulo da MOS. Os resultados mostraram que essas pastagens bem manejadas podem possibilitar um seqüestro de 6,1 a 12,8 Mg CO2 ha-1 ano-1 da atmosfera. Com a avaliação qualitativa da MOS, também foi possível obter resultados promissores na determinação da estabilidade da MOS. A detecção do aumento do conteúdo de C no solo foi acompanhada pela redução do grau de humificação, por meio da FIL. Esta redução na humificação foi devido à entrada de material orgânico mais lábil, ou seja, menos transformado. Na Fluorescência convencional e RPE, com amostras de AH em solução, os maiores graus de humificação foram obtidos para os AH dos tratamentos de pastagem, principalmente os que tiveram adição de calagem. O Ca2+, além de aumentar a atividade microbiana, pode complexar com os AH, associado ao aumento da estabilidade da MO. No sistema de PD de soja com renovação de cana-de-açúcar, os maiores teores de C foram obtidos nas amostras referentes aos sistemas sob PD após 7 anos sob esse manejo, em comparação com áreas sob manejo convencional. O acúmulo de MOS foi devido principalmente à preservação da cobertura vegetal associada com o não revolvimento do solo, rotação de culturas e a não queimada da cana-de-açúcar. Nessa área experimental, foi possível constatar um seqüestro de 0,15 a 5,29 Mg CO2 ha-1 ano-1 da atmosfera. Com relação à estabilidade da MO avaliada por Espectroscopia de FIL, verificou-se que o sistema de PD apresentou menor grau de humificação, devido à maior entrada de material orgânico lábil. Os resultados obtidos em área experimental de PD com grãos, com até 22 anos de duração, estão provavelmente associados com o tipo de solo analisado. Nos Latossolos com alto conteúdo de argila pode haver proteção física da MO, provavelmente impedindo alterações estruturais desse material, mesmo após longo período sem o revolvimento do solo. Outro fato importante é que o estudo de seqüestro de C depende muito da área avaliada, ou seja, delineamento do experimento, histórico do local, duração, condições climáticas, taxas de decomposição do C, produção de massa vegetal e aporte de resíduos. / Agriculture can play an important role in mitigating carbon dioxide (CO2) concentration in the atmosphere. Through photosynthesis, it is possible to convert CO2 from atmosphere to plant biomass, and moreover, through an adequate agricultural system CO3 can be stored in soil, characterizing \"carbon sequestration\". Nowadays, many researches want to understand the role of agriculture production, as no-tillage, and Brachiaria pastures, in carbon dynamics in soil. Studies about organic matter dynamics and stability are necessary, since variables such as carbon stocks and degree of humification can be evaluated, and as a result, to obtain essential parameters to CO2 mitigation to the atmosphere. This topic is inserted in some Global Climate Change interests. In this context, spectroscopic methods, for example, Electron Paramagnetic Resonance (EPR), UV-Vis light fluorescence and Laser Induced Fluorescence (LIF) can be fundamental in the stability of soil organic matter (SOM) evaluation. The present study aims to examine the SOM behavior in areas with carbon sequestration potential, through evaluation of carbon stocks in soils, in different tillage systems followed by characterization by spectroscopy. Therefore, the knowledge of the organic matter (OM) quantity is important in soil management regarding to a sustainable agriculture. However, little consistent information is found to compare and recommend the most adequate method to obtain satisfactory results for each study. Consequently, it was possible to evaluate the OM quantity in Oxisols by different methods and compare them, using coefficient of variation and principal component analysis, to propose the best methodology. In the tropical regions of Brazil, in Brachiaria decumbens pastureland, the results showed that the greatest SOM content occurred under pastureland, against the native dense Cerrado vegetation, after 27 years of experiment. The highest carbon stocks obtained by pasture samples were favored by accumulations of plant biomass on the soil surface, nitrogen input, besides Brachiaria root systems. According to the results obtained, the annual input of adequate amounts of limestone (2 t ha-1 addition and 1 t ha-1 year-1 reinforcement) and N seemed to be the best treatment regarding different pastureland treatments, mainly due to its higher C accumulation. The results also showed that non-degraded pastures can enable an annual sequestration rate ranging from 6.1 to 12.8 Mg CO2 ha-1 year-1. Qualitative evaluation of SOM also obtained satisfactory results on the soil surface. Results showed that higher C amount was followed by lower degree of humification, obtained by LIF. This lower humification was due to labile organic material, or greater fresh input of crop residues. In conventional fluorescence and EPR, with humic acids, the greatest degree of humification was obtained in pastures treatments, especially in treatments with lime input. Ca2+, in addition to increasing the biological activity, can combine with humic acids, increasing OM stability. In the no-tillage system of soya and sugar cane renovation, higher C amounts were obtained in no-tillage samples, after 7 years of experiment. The maintenance of a permanent vegetal cover, without soil disturbing and without sugar cane burning was essential to SOM accumulation against conventional management. In the no-tillage system, in a period of 7 years, it was possible to verify a sequestration rate ranging from 0.15 to 5.29 Mg CO2 ha-1 year-1. In relation to SOM stability by LIF, no-tillage presented lower degree of humification, due to input labile OM. The results obtained under no-tillage cropping system after 22 years are probably associated with the kind of soil analyzed. In Latossols, with high amount of clay, there may be a physical protection of OM, probably preventing structural changes in this material, even after a long period without soil disturbing. Another important factor is that C sequestration studies depend on the evaluated area, such as experiment outline, historical area, time, climate conditions, C decomposition rates, vegetal biomass production and residue input.

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. <br />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. <br />A utilização de ferramentas como a PCA e planejamento fatorial foi de grande relevância para a análise dos resultados e condução dos experimentos. <br />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. <br />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. <br />Tools as Principal component Analysis and factorial design were of such relevance for the results analysis and experiments execution. <br />The spectroscopic and chemical techniques showed that the benefits from the effluent addition in soil, even in a short-term experiment, can present changes. <br />The results for the humic acids samples concerning the particles size evidenced the behavior presented in recent studies, related to humic substances structures.

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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The influence of parent lithology on the development of soil biogeochemical environments and their microbial diversity is explored by characterising soil profiles with respect to their mineral, solution and organic chemistry. Soil profiles were collected from a total of 17 sites, above basalt, granodiorite, shale, sandstone and limestone, across Northern Ireland. The soil system developed above basalt was examined to assess the development of soil bio-physicochemical properties and microbial diversity through the profile. These basalt soils showed two distinct horizons have developed in the previous 15’000 years, where soils from the top 20 cm of the profile were highly influenced by the interactions of soil minerals with soil organic and biological processes. In line with the observed differences in soil properties the microbial community structure varied; in the surface soils the community composition was dominated by root-associated bacteria. However the relative abundance of phyla affiliated with nutrient-limited conditions increased in samples from the base of the profile. Detailed examination of the soil profiles above granodiorite, shale, sandstone and limestone revealed large variations in soil geochemistry between profiles, reflecting the mineral geochemistry of the parent rock. Molecular analysis of SOM revealed compositional changes with depth were comparable between profiles; however TOC concentrations were consistently higher in the soil profiles above basalt suggesting greater stabilisation of SOM in these soils. The chemistry of the soil waters was not reflective of the parent rocks; however variations in soil texture, specifically the abundance of less reactive residual minerals in the sandstone and limestone soils, led to higher concentrations of soluble elements in these soils. Soil pH and DOC were found to have a large control on buffering the release of free Al, Cr and Fe ions into solution. The microbial communities in near-surface soils were similar to each other, regardless of lithology, and were dominated by Proteobacteria, Actinobacteria, and Acidobacteria. However microbial diversity shifted with depth; the abundance of Actinobacteria decreased and Nitrospirae increased, and between rock types where soils next to the basalt, shale and granodiorite bedrock contained sequences affiliated with novel Candidate Phyla AD3 and GAL15. In these soils differences in SOM composition were the main driver of the observed variation with depth, however where labile SOM was depleted, mineral and solution geochemistry may have a larger control on the community composition. To assess the influence of parent lithology on selenium mobility, soils above basalt and granodiorite were amended with sodium selenate. Under anaerobic conditions, the proportion of soluble selenate removed varied (39-77 %) depending on the sample through a combination of abiotic and microbial reduction processes. However, under aerobic conditions, larger concentrations of selenate remained in solution (79-100%).