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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Biocarvão e adubação nitrogenada influenciando o crescimento e o estado nutricional de mudas de castanheiras-do-brasil em um latossolo da Amazônia Central

Gama, Romildo Torres da 28 February 2018 (has links)
Submitted by Inácio de Oliveira Lima Neto (inacio.neto@inpa.gov.br) on 2018-07-13T20:25:53Z No. of bitstreams: 2 DISSERTAÇÃO VERSÃO FINAL EM 4 de abril.pdf: 1507866 bytes, checksum: 1874f02b8fc898ea5a84dbd790cdea84 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-07-13T20:25:53Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO VERSÃO FINAL EM 4 de abril.pdf: 1507866 bytes, checksum: 1874f02b8fc898ea5a84dbd790cdea84 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-28 / Fundação de Amparo à Pesquisa do Estado da Bahia - FAPEB / Biochar can be used as a soil amendment, contributing to the recovery of degraded areas and increasing the agronomic efficiency of mineral and organic fertilizers. The objective of this research was to evaluate the effect of biochar and nitrogen fertilizer doses on changes in soil fertility, biomass production and nutritional status in Bertholletia excelsa seedlings. The experiment was conducted in a greenhouse for 210 days in 2017. The experimental design was completely randomized (DIC) in a factorial test (2x4) with 4 replicates. The factors were - absence and presence of biochar (0 and 40 t ha-1) and four increasing doses of nitrogen (0, 67,5, 135 and 270 kg ha-1) and consisted of 8 treatments (n = 32). The pyrolysed brazil nut shell was used as a source of bio-fuel at 500ºC. The soil used was a dystrophic Yellow Oxisols from Central Amazonia, removed from the subsurface layer (20-40 cm), under a secondary forest. Seedlings at the age of seven months were used. One month after transplanting, the diameter at 3,0 cm of the soil and the height of the plants were measured. The following parameters were calculated: relative height growth rate, relative diameter growth rate, absolute growth rate in height, absolute diameter growth rate, absolute height growth and Dickson quality index. pH values and nitrogen, phosphorus, potassium and calcium contents increased with the application of biochar. Micronutrient contents increased with increasing doses of N, except for magnesium. Increasing doses of N promoted greater development of the plant in the weight gain of the dry matter area. The biomass increased the dry matter weight of the roots. The quality index of Dickson did not show any significance among the treatments; on the other hand, the values were above 1, emphasizing the benefits of nitrogen fertilization. For the production of Brazil nut tree seedlings, no dose of N was indicated as ideal. Leaf phosphorus concentrations did not increase either because of increasing doses of N or BC. The foliar concentrations of Ca and iron and magnesium micronutrients had their values negatively affected by BC. In general, the various parameters of soil and plants increase in the intervals of 0 to 135 kg ha-1 of N. / O biocarvão pode ser usado como condicionador do solo, contribuindo para a recuperação de áreas degradadas e aumentando a eficiência agronômica dos fertilizantes minerais e orgânicos. O objetivo desta pesquisa foi avaliar o efeito do biocarvão e doses de fertilizantes nitrogenados nas mudanças da fertilidade do solo, produção de biomassa e estado nutricional em mudas de Bertholletia excelsa. O experimento foi conduzido em casa de vegetação durante 210 dias no ano de 2017. Empregou-se o delineamento experimental inteiramente casualizado (DIC) em ensaio fatorial (2x4) com 4 repetições. Sendo os fatores, ausência e presença de biocarvão (0 e 40 t ha-1) e quatro doses crescentes de nitrogênio (0, 67,5, 135 e 270 kg ha-1), constituído 8 tratamentos (n=32). Utilizou-se como fonte de biocarvão ouriço de castanheira-do-brasil pirolisado à 500ºC. O solo utilizado foi Latossolo Amarelo distrófico da Amazônia central, retirado da camada subsuperficial (20-40 cm), sob uma floresta secundária. Utilizou-se mudas com idade de sete meses. Um mês após o transplantio foram mensurados o diâmetro a 3,0 cm do solo e a altura das plantas. De posse dessas medidas foram calculados os seguintes parâmetros: taxa de crescimento relativo em altura, taxa de crescimento relativo em diâmetro, taxa de crescimento absoluto em altura, taxa de crescimento absoluto em diâmetro, crescimento absoluto em altura e índice de qualidade de Dickson.Os valores de pH e os teores de nitrogênio, fósforo,potássio e cálcio aumentaram com a aplicação do biocarvão. Os teores dos micronutrientes aumentaram com as doses crescentes de N, com exceção do magnésio. As doses crescentes de N promoveram maior desenvolvimento da planta no ganho de peso da matéria seca da parte área. O biocarvão aumentou os valores do peso da matéria seca das raízes. O índice de qualidade de Dickson não mostrou significância entre os tratamentos, por outro lado, os valores ficaram acima de 1, enfatizado os benefícios da fertilização nitrogenada. Para a produção de mudas de castanheiras-do-brasil, nenhuma dose de N foi apontada como ideal. As concentrações foliares de fósforo não tiveram aumentos seja por efeito das doses crescente de N ou do BC. As concentrações foliares de Ca e dos micronutrientes ferro e magnésio tiveram seus valores afetados negativamente pelo BC. De modo geral os diversos parâmetros do solo e das plantas aumentam nos intervalos de 0 a 135 kg ha-1 de N.
12

Economic and environmental potential of biochar : a "win-win" solution for China's straw?

Clare, Abigail Jane January 2015 (has links)
Biochar has often been described as a "win-win" technology for soil fertility, agronomic yields, carbon sequestration and poverty reduction. However, despite a growing body of physical research evidence to support these claims, there is much less socio-economic evidence for biochar's potential to achieve these "winwin" outcomes in real-world systems. Consequently, debates about biochar and its potential to contribute to sustainable development have often been polarised between extremes of opinion, with some claiming it is a key technology for mitigating climate change, and others warning of potentially dire effects for ecosystems and vulnerable populations. This inspired the objective for this PhD, which is to generate research that can inform and moderate the debate on biochar's win-win potential. Guided by the theory of ecological modernisation, this PhD aimed to generate a body of applied, policy-relevant research on the economic and environmental potential of biochar as a win-win use of biomass resources. It was important to adopt geographical and biomass boundaries for the research to provide a meaningful and focused contribution, therefore the research is focused on China and its agricultural straw residues. One of the central claims for biochar is that it can improve crop yields and, consequently, reduce poverty for smallholder farmers. This thesis investigated this from a socio-economic perspective using farm-scale linear programming models with primary data from interviews conducted across four contrasting Chinese agricultural systems. The results suggest that biochar is unlikely to provide even minor economic gains, let alone poverty-reducing change, to smallholder farmers in these systems. If biochar is not economic for farmers, there is a possibility that economies of scale made possible by business ventures could reduce the marginal costs per unit of biochar product and/or that governments/climate finance institutions may be interested in subsidising this technology where it has significant carbon mitigation impacts. Thus the next research question was whether biochar might be a profitable investment for businesses in China, and further whether businesses might also profit from carbon credits/subsidies where biochar's carbon sequestration potential is valued either by carbon markets or by climate conscious governments willing to provide appropriate incentives. Life-cycle and cost-benefit analyses demonstrated that, when compared to the main competing uses for straw feedstocks (briquetting for combustion in boilers, and gasification for electricity generation), pyrolysis of straw to produce biochar makes a financial loss under all subsidy scenarios considered, and is the least cost-effective technology for carbon sequestration. Overall it seems biochar made from China's straw feedstocks is not currently a win-win option for smallholder farmers, business investors or national/international climate mitigation strategies. In light of the relative dominance of bioenergy over biochar production as a financial and climate mitigating option for China's straw, the focus of the thesis shifts to explore win-win scenarios in this domain. Here the results are more promising. Combining a unique geographical dataset of China's coal fired powerstations and straw location with data on energy economics, the model suggests a small tweak to China's bioenergy subsidy system (an extension of the existing feed-in-tariff to include low energy replacement ratio cofiring) could contribute 42-62% of China's 2020 target to install 30GW of renewable energy generation capacity: a classic win-win scenario for the Chinese government's bioenergy targets, bioenergy investors and global climate change. Overall this thesis offers two main findings to the literature. Firstly it demonstrates that, within its current high application rate model, biochar will struggle to compete as a win-win strategy when viewed through financial and carbon sequestration lenses. However, secondly, it suggests that win-win strategies are available for China's straw resources under cofiring bioenergy applications. The thesis concludes with a critical discussion of these results in relation to the theory of ecological modernisation and the concept of win-wins.
13

Effects of Biochar Recycling on Switchgrass Growth and Soil and Water Quality in Bioenergy Production Systems

Husmoen, Derek Howard 2011 May 1900 (has links)
Intensive biomass production in emerging bioenergy systems could increase nonpoint-source sediment and nutrient losses and impair surface and groundwater quality. Recycling biochar, a charcoal byproduct from pyrolysis of biomass, provides potential sources of mineral nutrients and organic carbon for sustaining biomass productivity and preserving soil and water. Yet, research is needed to verify that recycling of pyrolysis biochars will enhance crop growth and soil and environmental quality similar to black carbon or biochar derived from burning of biomass in tropical or Terra Preta soils. The experimental design of this study consisted of 3 replications and four biochar rates (0, 4, 16, and 64 Mg ha-1) incorporated in both a sandy loam and clay soil with and without fertilizer sources of N, P, and K. The sandy loam and clay soils were studied in separate experiments within a set of 24 box lysimeters seeded with switchgrass. Simulated rain was applied at 50 percent and 100 percent establishment of switchgrass for each soil type. Runoff and leachate were collected and analyzed for total and dissolved N, P, K and organic C. After the second rain event, each soil type and the accumulated switchgrass was sampled and analyzed. In the Boonville soil, biochar applied at 64 Mg ha-1 decreased switchgrass emergence from 42 percent to 14 percent when compared to soil alone. In the Burleson soil, 64 Mg ha-1 biochar had no effect (P > 0.05) on biomass production or leaf area index (LAI). Fertilizer N, P, and K had no effect (P > 0.05) on switchgrass emergence for either soil, but did increase (P < 0.001) N, P, and K uptake, biomass production, and LAI. Increasing rates of biochar increased (P < 0.001) runoff concentrations of DRP during each rain event for both the Boonville and Burleson soils. Four rates of biochar receiving supplemental N, P, and K fertilizer also resulted in greater runoff concentrations of DRP. Emergence tests under increased heat showed electrical conductivities of soil-water solutions to be as high as 600 microS cm-1, even after biochar was washed with acetone and water to remove residual oils and tars and soluble salts. Increasing biochar rates decreased soil bulk density and increased pH and SOC in the 0- to 5-cm depth of soil. As a result of high nutrient recovery during pyrolysis (58 percent of total N, 86 percent of total P and 101 percent of total K), high rates of biochar applied at 64 Mg ha-1 increased mass losses of TN, TP, and TK from both soils. Yet, the mass balance of nutrients showed a surplus of N, P, and K at 64 Mg ha-1 biochar, which suggests some nutrient inputs are not plant available and remain in soil. Careful management of biochar, especially at high rates with these high nutrient contents, is critical when trying to improve soil fertility while protecting water quality.
14

The Potential for Activated Biochar to Remove Waterborne Viruses from Environmental Waters

Florey, James 2012 May 1900 (has links)
The need for clean potable water and sustainable energy are two current and pressing issues with implications affecting the global population. Renewed interests in alternative energy have prompted researchers to investigate the full capacity of biofuels. These interests have led to not only the examination of current method limitations, but also to the investigation of new conversion methods. One promising method for bioenergy production is pyrolysis of lignocellulosic feedstocks. Through pyrolysis, a single crop may produce ethanol, bio-oil, and/or gaseous energy (syngas). The remaining solid phase product is a black carbon dubbed 'biochar'. In the current study, biochar was used as a both an unamended sorbent and a precursor to form powdered activated carbons (PACs) capable of removing waterborne viruses. Biochar was activated with KOH, ZnCl2, and H3PO4 and analyzed using the Brunauer, Emmett and Teller (BET) method, a combination of Kjeldahl digest and ICP-MS, and scanning electron microscopy (SEM). Sorbents were tested in batch studies using phosphate buffered saline (PBS), surface water, and groundwater. Bacteriophages MS2 and thetaX174 served as viral surrogates. All activation treatments significantly increased surface area, up to 1495.5 m2/g (KOH-activated). While the non-activated biochar was not effective in virus removal, the KOH-activated PAC had tremendous removal in the PBS/MS2 batch (mean 98.7% removal, up to 6.2 x 109 particles/mL, as compared to the Darco S-51: 82.3%). As evidenced by this study, sorption efficiency will be governed by viral species, carbon type and concentration, and water quality. The results of this study indicate that biochar can serve as a precursor for a highly porous and effective PAC, capable of removing waterborne viruses from environmental waters.
15

Biochar e Trichoderma harzianum no controle de Macrophomina phaseolina

Araujo, Alyson Silva de 02 March 2018 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, Programa de Pós-Graduação em Agronomia, 2018. / Submitted by Raquel Viana (raquelviana@bce.unb.br) on 2018-08-06T18:08:37Z No. of bitstreams: 1 2018_AlysonSilvadeAraujo.pdf: 3066304 bytes, checksum: cf95de43c6b402d277baf1937a0b984f (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2018-08-08T19:59:39Z (GMT) No. of bitstreams: 1 2018_AlysonSilvadeAraujo.pdf: 3066304 bytes, checksum: cf95de43c6b402d277baf1937a0b984f (MD5) / Made available in DSpace on 2018-08-08T19:59:39Z (GMT). No. of bitstreams: 1 2018_AlysonSilvadeAraujo.pdf: 3066304 bytes, checksum: cf95de43c6b402d277baf1937a0b984f (MD5) Previous issue date: 2018-08-06 / Macrophomina phaseolina é um importante patógeno habitante do solo, associado ao “damping-off” e podridões de raízes e caules em mais de 700 espécies de plantas. O uso de biochar (BCH) de lodo de esgoto, aplicado ao solo, tem despertado interesse em diferentes estudos para o controle de doenças em plantas, proporcionando uma inibição ou mesmo suprimindo fitopatógenos. O controle biológico é evidenciado por ser uma alternativa eficaz para o manejo de diferentes fitopatógenos. Trichoderma é um dos mais estudados e utilizados agentes de biocontrole de doenças vegetais em todo o mundo. O objetivo desse trabalho foi avaliar os efeitos da aplicação ao solo de BCH, Trichoderma harzianum e da associação BCH + T. harzianum sobre M. phaseolina em aspectos agronômicos das culturas de soja, milho, feijão e algodão inoculadas ou não com o fitopatógeno. Foi avaliado o efeito direto de concentrações (0,0; 0,5; 1,0; 2,0; 5,0 e 10,0%) de BCH sobre o crescimento micelial de isolados de M. phaseolina. Foi observado ainda a capacidade de biocontrole por meio do uso do pareamento de cultura (T. harzianum x M. phaseolina) com ou sem biochar. Além disso, foi avaliado o uso de BCH, do T. harzianum, e da associação BCH + T. harzianum em plantas de feijão e soja para controle de M. phaseolina em experimento conduzido em casa de vegetação. Biochar de lodo de esgoto, pirolisado a 500 ºC e utilizado em baixa concentração (0,5%), possui efeito direto no controle in vitro de diferentes isolados de M. phaseolina. No entanto, concentrações mais elevadas do BCH estimulou o crescimento do fungo. Trichoderma harzianum (linhagem 1306) inibiu o crescimento micelial de M. phaseolina, em meio de cultura com ou sem biochar. Macrophomina phaseolina afeta negativamente: (a) a germinação e sobrevivência de plantas de soja e; (b) a germinação, sobrevivência e número de vagens de plantas de feijão comum. O isolado 428 de M. phaseolina reduziu todos os índices agronômicos (germinação, sobrevivência, número de vagens, massa fresca e seca) de plantas de feijão. O uso de BCH aumentou o número de vagens em plantas de soja, inoculadas ou não com M. phaseolina. A associação T. harzianum + BCH de lodo de esgoto aumentou o número de vagens, massa fresca e seca de plantas de feijão, inoculadas ou não com M. phaseolina. / Macrophomina phaseolina is an important soil pathogen, associated with “damping-off” and root and stem rot in more than 700 plant species. The use of biochar (BCH) of sewage sludge applied to the soil, has aroused interest in studies for the control of diseases in plants, providing an inhibition of plant pathogens. Biological control is evidenced as an effective alternative for the management of different phytopathogens. Trichoderma is one of the most studied and used biocontrol agents of plant diseases worldwide. The objective of this work was to evaluate the effects of BCH, Trichoderma harzianum and BCH + T. harzianum on M. phaseolina and on agronomic aspects of soybeans, maize, beans and cotton inoculated or not with M. phaseolina. The direct effect of concentrations (0.0, 0.5, 1.0, 2.0, 5.0 and 10.0%) of BCH on the mycelial growth of M. phaseolina isolates was evaluated. It was also observed the biocontrol capacity using culture pairing (T. harzianum x M. phaseolina) with or without biochar. In addition, the use of BCH, T. harzianum, and the association BCH + T. harzianum in bean and soybean plants were evaluated for M. phaseolina control in a greenhouse experiment. Biochar of sewage sludge, pyrolyzed at 500 ºC and used in low concentration (0.5%), has direct effect on the in vitro control of isolates of M. phaseolina. However, higher concentrations of BCH stimulated fungal growth. Trichoderma harzianum (strain 1306) inhibited the mycelial growth of M. phaseolina, in culture medium with or without biochar. Macrophomina phaseolina negatively affects: (a) the germination and survival of soybean plants, and; (b) the germination, survival and number of pods of common bean plants. Isolate 428 from M. phaseolina reduced all agronomic characteristics (germination, survival, number of pods, fresh and dry mass) of bean plants. The use of BCH increased the number of pods in soybean plants, inoculated or not with M. phaseolina. The association of T. harzianum + BCH of sewage sludge increased the number of pods, fresh and dry mass of bean plants, whether or not inoculated with M. phaseolina.
16

The impacts of biochar application on soil hydrology, erosion and related properties

Aston, Stephen January 2014 (has links)
Biochar production and application to soil can mitigate climate change and improve soil quality. This thesis investigated the influence of biochar preparation methods and application rates on the hydrological and erosional characteristics of biochars themselves and the soils to which they were applied. Biochar hydrophobicity was influenced by feedstock and decreased with increasing highest treatment temperature (HTT). Biochar did not influence soil wettability and the effect of HTT on biochar porosity was more important for soil water-holding capacity than its effect on hydrophobicity. HTT affected biochar yield, cation exchange-capacity and provision of fungal substrates. HTT also significantly influenced the effect of biochar on soil suction. Smaller feedstock particles produced biochars that were slightly more hydrophobic than those produced from larger particles. The effects of biochar application on the properties of sandy loam were influenced by biochar particle size, because larger particles had less effect on bulk density and had slower water uptake. A low biochar application rate (5 g kg-1) had no effect on the aggregate stability of a silt loam and did not affect the hydrological and erosional response of the soil under simulated rainfall. Application rates of 25 and 50 g kg-1 reduced aggregate stability, which led to surface sealing and overland flow generation occurring more readily. However, there was no more erosion of these soils than those with low or zero biochar content, and the crusts formed by seal drying were much weaker than those formed on soils with low or zero biochar. Biochar was preferentially eroded from the soils, regardless of the application rate used. HTT and particle size can have important implications both for the properties of biochar itself and for its effects on soil properties. However, biochar may only substantially influence soil hydrology and erosion when applied at sufficiently high rates.
17

Imobilização de fosfatos em microesferas poliméricas contendo biochar : preparação, caracterização e liberação lenta em sistemas aquosos /

Domingues, Murilo Teles. January 2015 (has links)
Orientador: André Henrique Rosa / Banca: Luciane Pimenta Cruz Romão / Banca: Admilson Irio Ribeiro / Resumo: A população mundial vem crescendo e pode atingir 9 bilhões de pessoas até o ano de 2050. Isso acarretará em uma maior geração de alimentos para atender a essa demanda. Na agricultura, por exemplo, serão utilizadas maiores quantidades de fertilizantes convencionais para o aumento da produção agrícola, favorecendo a poluição pela lixiviação de nutrientes para os recursos hídricos. Desta maneira, como uma alternativa para substituir fertilizantes convencionais, este trabalho teve como objetivo principal preparar, caracterizar e avaliar, em meio aquoso, a liberação lenta de fósforo por microesferas poliméricas de alginato contendo biochar (matéria orgânica pirolisada). Para isso, produziram-se cinco tipos de biochars a partir do bagaço de cana-de-açúcar ao aquecêlo às temperaturas de 300, 400, 500, 600 e 700 °C (B300, B400, B500, B600 e B700, respectivamente). O aumento da temperatura de pirólise influenciou no aumento do pH do material formado devido a uma maior formação de carbonatos e diminuição de grupos funcionais com características ácidas. O rendimento foi inversamente proporcional ao aumento da temperatura, uma vez que, ao se elevar a temperatura se eleva a decomposição da matéria orgânica, obtendo assim um menor rendimento. O B300 e o B400 apresentaram resquícios de hemicelulose em sua composição, o que comprovaria que a pirólise até a temperatura de 400 °C, e as condições aqui adotadas, não foram suficientes para a decomposição completa desta estrutura do material. O aumento da temperatura de pirólise aumentou a aromaticidade no material e diminuiu sua hidrofilicidade, ou seja, sua afinidade por água. O B700 apresentou um maior teor de cinzas que poderiam servir como nutrientes às plantas, em contrapartida, o B300 e o B400 possuem maiores teores de matéria orgânica, que podem ser mais facilmente degradados pelos microrganismos. Foi observado a presença de poros nos biochars a partir da... / Abstract: The world population is growing and can reach 9 billion people by the year 2050. This will result in greater production of food to meet this demand. In agriculture, for example, will be used larger amounts of conventional fertilizers to increase agricultural production, increasing the leaching of nutrients, such as phosphorus, for water resources, polluting them. Thus, as an alternative to replace conventional fertilizers, this study aimed to prepare, characterize and evaluate, in an aqueous medium, the phosphorus slow release of polymeric alginate microspheres containing biochar (pyrolyzed organic matter). To achieve that, were produced five kinds of biochars from sugarcane bagasse to heat it to temperatures of 300, 400, 500, 600 and 700 °C (B300, B400, B500, B600 and B700, respectively). The increasing in pyrolysis temperature rises the pH of the formed material due to an increased formation of carbonates and reduction of functional groups with acidic characteristics. The yield was inversely proportional to the temperature increasing, since, when raise the temperature rises the decomposition of organic matter, thereby obtaining a lower yield. The B300 and B400 showed still have the remnants of hemicellulose in its composition, which would prove that the pyrolysis up to 400 °C, and the conditions here adopted, were not sufficient to complete decomposition of this structure in the sugarcane bagasse. The increase in pyrolysis temperature increased aromaticity and decreased hydrophilicity, or its affinity for water. The B700 had higher ash content that could serve as nutrients for plants, however, the B300 and B400 have the highest content of organic matter, which can be more easily degraded by microorganisms. It was observed the presence of pores in biochars since 300 °C pyrolysis temperature, but it is noted that from 500 °C biochar showed different structural variants, resulting in different pore complex. In the phosphorus release ... / Mestre
18

Aplica??o de carv?o vegetal e nitrog?nio influenciando propriedades f?sicas e qu?micas do solo e massa seca de arroz

Carvalho, Mary Anne Barbosa de 17 December 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-16T16:10:48Z No. of bitstreams: 1 MaryAnneBarbosaDeCarvalho_DISSERT.pdf: 1690612 bytes, checksum: 30220cc3a7a498f6f81552fe46a0c066 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2017-01-16T16:17:10Z (GMT) No. of bitstreams: 1 MaryAnneBarbosaDeCarvalho_DISSERT.pdf: 1690612 bytes, checksum: 30220cc3a7a498f6f81552fe46a0c066 (MD5) / Made available in DSpace on 2017-01-16T16:17:10Z (GMT). No. of bitstreams: 1 MaryAnneBarbosaDeCarvalho_DISSERT.pdf: 1690612 bytes, checksum: 30220cc3a7a498f6f81552fe46a0c066 (MD5) Previous issue date: 2014-12-17 / A degrada??o dos solos agr?colas causa problemas produtivos e ambientais, com consequ?ncias econ?micas e sociais para as popula??es. Al?m das perdas de solo e de sua fertilidade poderem inviabilizar a atividade produtiva, existe grande preocupa??o com a emiss?o para a atmosfera de gases que contribuem para o aquecimento do planeta. Assim sendo, o objetivo do trabalho ? avaliar a aplica??o de biocarv?o nas propriedades f?sicas e qu?micas do solo e na massa seca do arroz. O experimento foi desenvolvido em casa de vegeta??o na Unidade Acad?mica Especializada em Ci?ncias Agr?rias da Universidade Federal do Rio Grande do Norte-UFRN, em Maca?ba-RN. O delineamento estat?stico foi o inteiramente casualizado, em esquema fatorial 4x4, contando de doses de biocarv?o(0, 3500, 7000 e 10500 kg ha-1) e doses de nitrog?nio (0, 30, 60 e 90 kg ha-1) correspondendo a 16 tratamentos. O solo foi misturado com as respectivas doses, em seguida colocado em vasos de 10 L, utilizando como planta indicadora o arroz de terras altas. As vari?veis analisadas foram ? reten??o de ?gua, a densidade do solo, a massa seca da parte a?rea do arroz e as propriedades qu?micas. A reten??o de ?gua no solo apresentou efeito linear positivo das doses de biocarv?o; A densidade do solo foi influenciada pela intera??o entre doses de biocarv?o e de nitrog?nio, cujo desdobramento revelou efeito quadr?tico da dose de biocarv?o sobre a densidade do solo apenas na dose zero de nitrog?nio; Para massa seca do arroz houve intera??o de doses de nitrog?nio dentro de doses de biocarv?o observando-se na dose zero de biocarv?o o efeito quadr?tico apenas do nitrog?nio; As propriedades qu?micas foram significativos os efeitos da dose de biocarv?o para pH e CaMg (p<0,05) e para K (p<0,01). N?o houve efeito significativo das doses de nitrog?nio (30 e 60 kg ha-1) nem da intera??o entre doses de biocarv?o e de nitrog?nio. Conclui-se ser necess?ria a condu??o do experimento e o acompanhamento de resultados na mesma ?rea em longo prazo. Assim, a evolu??o nas caracter?sticas qu?micas e f?sicas do solo pode ser avaliada, gerando informa??es consistentes sobre o potencial do biocarv?o como condicionador de solo e fertilizante. / A degrada??o dos solos agr?colas causa problemas produtivos e ambientais, com consequ?ncias econ?micas e sociais para as popula??es. Al?m das perdas de solo e de sua fertilidade poderem inviabilizar a atividade produtiva, existe grande preocupa??o com a emiss?o para a atmosfera de gases que contribuem para o aquecimento do planeta. Assim sendo, o objetivo do trabalho ? avaliar a aplica??o de biocarv?o nas propriedades f?sicas e qu?micas do solo e na massa seca do arroz. O experimento foi desenvolvido em casa de vegeta??o na Unidade Acad?mica Especializada em Ci?ncias Agr?rias da Universidade Federal do Rio Grande do Norte-UFRN, em Maca?ba-RN. O delineamento estat?stico foi o inteiramente casualizado, em esquema fatorial 4x4, contando de doses de biocarv?o(0, 3500, 7000 e 10500 kg ha-1) e doses de nitrog?nio (0, 30, 60 e 90 kg ha-1) correspondendo a 16 tratamentos. O solo foi misturado com as respectivas doses, em seguida colocado em vasos de 10 L, utilizando como planta indicadora o arroz de terras altas. As vari?veis analisadas foram ? reten??o de ?gua, a densidade do solo, a massa seca da parte a?rea do arroz e as propriedades qu?micas. A reten??o de ?gua no solo apresentou efeito linear positivo das doses de biocarv?o; A densidade do solo foi influenciada pela intera??o entre doses de biocarv?o e de nitrog?nio, cujo desdobramento revelou efeito quadr?tico da dose de biocarv?o sobre a densidade do solo apenas na dose zero de nitrog?nio; Para massa seca do arroz houve intera??o de doses de nitrog?nio dentro de doses de biocarv?o observando-se na dose zero de biocarv?o o efeito quadr?tico apenas do nitrog?nio; As propriedades qu?micas foram significativos os efeitos da dose de biocarv?o para pH e CaMg (p<0,05) e para K (p<0,01). N?o houve efeito significativo das doses de nitrog?nio (30 e 60 kg ha-1) nem da intera??o entre doses de biocarv?o e de nitrog?nio. Conclui-se ser necess?ria a condu??o do experimento e o acompanhamento de resultados na mesma ?rea em longo prazo. Assim, a evolu??o nas caracter?sticas qu?micas e f?sicas do solo pode ser avaliada, gerando informa??es consistentes sobre o potencial do biocarv?o como condicionador de solo e fertilizante.
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Uso de finos de carvão e esterco de galinha em solo cultivado com milho e na produção de mudas de café

RIBEIRO, P. H. 30 March 2016 (has links)
Made available in DSpace on 2018-08-01T22:33:17Z (GMT). No. of bitstreams: 1 tese_7169_Paulo Henrique Ribeiro.pdf: 554403 bytes, checksum: 0924f41f26657a38878e12dccf783790 (MD5) Previous issue date: 2016-03-30 / O composto orgânico formado por finos de carvão vegetal e esterco de galinha pode melhorar a fertilidade do solo e a produção vegetal. O objetivo dessa tese foi avaliar as características químicas e físicas de finos de carvão de eucalipto incubados com esterco de galinha, a produção de mudas de café e a resposta da cultura do milho à aplicação dos materiais orgânicos produzidos. Quatro granulometrias de fino de carvão (4-2, 2-1, 1-0,29 e <0,29 mm) foram incubadas na proporção de 1:1 (volume) com esterco de galinha, procedendo cinco coletas para análise (0, 45, 90, 135 e 180 dias de incubação). Os materiais foram aplicados em solo de vasos para cultivo de milho (30 dias) em casa de vegetação, em sulcos na linha de cultivo de milho em campo (ponto de silagem) e nos substratos para produção de mudas clonais de café conilon. As misturas incubadas e o esterco puro apresentaram como características em destaque: alto pH (8,0 a 9,1), que acarretou baixos teores de N (1,2-1,7%); teores altos de cinzas (40,4-67,9%) e P total (18,4-50 g kg-1). O esterco puro foi o tratamento que proporcionou o melhor crescimento do milho cultivado em vasos e campo, e melhor desenvolvimento das mudas de café. A aplicação de finos de carvão no solo deve ser limitada à dose para correção de acidez, devido à sua alcalinidade. Essa dose ainda aportará P, K, Ca e Mg, promovendo economia na aplicação de fertilizantes.
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Diseño y Desarrollo de Pequeñas Unidades de Gasificación de Madera para Aplicaciones de Generación de Energía Térmica y Cogeneración a Baja Escala

Palatnic Ampuero, María Esmeralda January 2011 (has links)
El proyecto pretende diseñar y desarrollar, hasta un nivel de planos de construcción, una unidad gasificadora de biomasa para producción de energía térmica y eléctrica de 10 - 15 kW de capacidad. En Chile existe unos 99.000 hogares que carecen de facilidades para acceder a los servicios de fuentes de energía, ya sea eléctrica y/o gas combustible. La mayoría de esos hogares se encuentran ubicados en la zona sur de nuestro país, con gran acceso a los desechos de biomasa forestal y agrícola. Teniendo en cuenta estos factores se deduce que la gasificación de biomasa constituye una novedosa tecnología para solucionar las necesidades eléctricas y térmicas básicas del consumo humano. Actualmente, existe una gran diversidad de proyectos de gasificación de biomasa en el mundo, pero en su mayoría corresponden a centrales con potencias sobre 200 kW, lo que genera un gran incentivo de investigación al desarrollo comercial de unidades de baja potencia. Un atractivo importante del proceso de gasificación de biomasa en esta memoria es la generación de biochar, un carboncillo que sirve para mejorar las tierras de cultivos. Se diseñó una unidad gasificadora con innovaciones que permiten reducir el nivel de alquitranes del syngas producido. Éstas corresponden a un lecho modelo Imbert para una gasificación de tiro inverso, un sistema de inyección de aire secundario y precalentamiento el aire de gasificación. La unidad de gasificación - biochar se compone del lecho de gasificación, un enfriador de gases, un ciclón y un filtro de mangas La unidad de gasificación - biochar produce syngas suficiente para alimentar un generador de unos 10 kW aproximadamente o para ser consumido como gas combustible, agua caliente sanitaria y biochar. El trabajo especifica todas las modificaciones necesarias para implementar el gasificador – biochar en una vivienda tipo, conformada por 4 personas en una casa de 3-4 habitaciones de 100 – 120 m2 y se detallan los equipos auxiliares requeridos y las condiciones de operación y uso del equipo. La evaluación técnico – económica revela que la gasificación – biochar es altamente competitiva en la resolución de la problemática de viviendas que no tienen fácil acceso a servicios básicos de energía eléctrica y térmica, en comparación con otras alternativas existentes. Como negocio, el servicio de armado de unidades gasificadoras presenta una buena opción de inversión ya que tiene retornos monetarios interesantes y bajas barreras de entrada al mercado.

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