Orientador: Carolina Fernandes / Banca: Maria Helena Moraes Spinelli / Banca: José Eduardo Corá / Banca: Adolfo Valente Marcelo / Banca: Edson Luiz Mendes Coutinho / Resumo: No período de reforma do canavial, em geral, o preparo do solo para o plantio é realizado em área total, visando promover melhor desenvolvimento do sistema radicular. Todavia, a realização desta prática provoca alterações na estrutura do solo, em função do tráfego de máquinas agrícolas desde a etapa de preparo do solo até a colheita, podendo comprometer o crescimento e a produtividade da cana-de-açúcar. Assim, com este estudo, objetivou-se: i - avaliar o crescimento e a produtividade de colmos da cana-de-açúcar cultivada em Latossolo e Argissolo, submetidos à escarificação em linha de plantio e em área total e ii - avaliar os efeitos do local da escarificação sobre os atributos físicos do solo e sua relação com a produtividade de colmos e a qualidade da cana-de-açúcar, cultivada em Latossolo e Argissolo, seis meses após o plantio. O delineamento experimental foi em parcelas grandes pareadas. Os tratamentos foram constituídos de dois locais de escarificação do solo: escarificação na linha de plantio (ELP) e escarificação em área total (EAT), em Latossolo e em Argissolo, localizados nos municípios de Guariba e Monte Alto, respectivamente. Para atender ao primeiro objetivo, avaliou-se o número de perfilhos, o número de folhas verdes e mortas por planta, a área foliar, o índice de área foliar, a altura da planta e a massa seca dos colmos, folhas, ponteiro e total, sendo estas mensuradas em seis avaliações durante o ciclo da cultura. O Argissolo submetido à ELP interferiu no perfi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the period of sugarcane field reform, soil tillage for planting is generally carried out in total area in order to promote a better root system development. However, this agricultural practice causes changes in soil structure due to the traffic of agricultural machinery from soil tillage to harvesting, which may compromise growth and productivity of sugarcane. The aim of this study was to: i - assess the growth and productivity of sugarcane stalks cultivated in an Oxisol and Ultisol undergoing chiseling in the planting row and in the total area; and ii) assess the effects of the chiseling site on soil physical attributes and their relation with stalk productivity and sugarcane quality six months after planting in an Oxisol and Ultisol. The experimental design was a large paired-plot design with treatments consisting of chiseling in the planting row (CPR) and chiseling in total area (CTA) in an Oxisol and Ultisol located in Guariba and Monte Alto, respectively. In order to meet the first objective, the number of tillers, number of green and dead leaves per plant, leaf area, leaf area index, plant height, and dry matter of stems, leaves, pointer, and total were measured in six assessments during the crop cycle. The Ultisol undergoing CPR interfered with crop tillering, presenting the lowest number of tillers at 115 DAP when approximately 1519 degree-days were accumulated when compared to the same soil undergoing CTA. Soil tillage with chiseling in the planting row may be rep... (Complete abstract click electronic access below) / Doutor

Orientador: Admilson Irio Ribeiro / Resumo: As questões ambientais que envolvem os efeitos do manejo e da degradação do solo necessitam de forma acelerada de pesquisa e muita extensão. Novos saberes e conhecimentos têm alcançado parte da comunidade acadêmica, mas ainda está aquém das necessidades para técnicos e leigos envolvidos em trazer soluções para problemas da ocupação, uso e degradação das terras. O manejo e recuperação ambiental de áreas degradadas são complexos e requerem diferentes tecnologias para o diagnóstico e avaliação. O uso de indicadores como diâmetro médio geométrico e distribuição percentual de agregado são parâmetros de uso consolidados, mas trazem limitações para questões complexas como o diagnostico do estado e condição de agregação do solo. A agregação do solo vem sendo estudada desde o inicio do século passado, mas são poucos os avanços conseguidos em popularizar a analise de agregação do solo agrícola como uma ferramenta laboratorial e prática. Além de que, falta conhecimento para popularizar a condição de agregação como informação de uso corrente. O uso de imagens obtidas e processadas em alta resolução permite sua aplicação em diferentes ramos da ciência, podendo ser aplicada nos estudos relacionados com o processo de agregação permitindo viabilizar o mais conhecimento ao processo. Este trabalho tem como objetivo desenvolver uma proposta metodológica para determinar a condição da qualidade de agregação, com base na tipificação de agregados e nos efeitos da variabilidade de composição em amos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Environmental issues involving the soil management effects and degradation are increasing and need to be extensively researched to be managed. New knowledge about solutions has been produced by academic research, but is still insufficient to solve the problems faced by technicians and other people involved to the field land use planning and degradation problems. Furthermore, the management of soil quality and land reclamation is complex, requiring different technologies for diagnosis and evaluation. The use of indicators, such as geometric mean diameter and percentage distribution of aggregate size, represents classical approaches, but both have limitations in treating the complexity of soil aggregation process. The soil aggregation has been studied since the beginning of the last century, but few advances have been made to popularize it to analyze agricultural soil quality. There are several difficulties to develop laboratory routines and practical tool to evaluate it. The use and processing of high resolution images have been widely applied in several fields of science and represents an interesting solution to study soil aggregation. To fill the existing gap, this works presents a methodological proposal to assess the quality of soil aggregation, by a classification of soil aggregates in terms of composition and variability. Agricultural soil aggregates were analyzed by three attributes: shape, surface and biogenesis. These parameters were used as indicators of soil aggrega... (Complete abstract click electronic access below) / Doutor

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 150-155. / by Paul Christopher Damian Milly. / M.S.

No description available.

Temperature, one of the most influential factors controlling the growth and distribution of plants, was measured during a three month summer period within several stands of vegetation. The stands represented four distinct plant communities: sagebrush-grass, mountain brush, aspen, and conifer. Measurements were obtained by a sucrose inversion method which gave exponential average or effective mean temperature (eT) values. Registerants, small glass vials filled with a sucrose-buffer solution, were placed in the air 10 decimeters above the ground level and in the soil 1, 5, and 10 decimeters below the ground level. The sites were carefully described with respect to plant cover and composition, soil profile, soil moisture, precipitation, elevation, aspect, and slope. Each site and plant community varied with respect to some of these factors. Several prominent relationships between the air and soil temperatures and various site factors were encountered. The sagebrush-grass and mountain brush sites had significantly higher temperatures than the aspen and conifer sites. Air and soil temperatures varied inversely with elevation. Soil temperatures varied inversely with soil depth and the variation was statistically significant. Soil temperatures at the one decimeter depth in adjacent sites were nearly 2° C higher in the site with a sparse shrub cover than in the site with a very dense shrub cover. On adjacent sites with opposite exposures the south exposure had soil temperatures which were nearly 6° C higher than the north exposure. Moist sites had lower temperatures than dry sites. Sites with 2 inches of litter and duff had cooler soil temperatures than sites with only 1 inch. Temperature differences between plant communities were measured with the sucrose inversion method even though the various site factors also had their effect upon the temperatures. It was not the intent of this paper to interpret interactions of the various site factors with temperature. It is concluded that the sucrose inversion method of temperature measurement is an easy to use, inexpensive, reliable method for use in ecological studies.

No description available.

Harvesting of forested wetlands in the Atlantic and Gulf lower coastal plains has the potential to cause intense site disturbance. Often, as a result of poor pre-harvest planning, silvicultural activities are performed on wetland soils highly susceptible to rutting and puddling. Potential decreases in pine productivity have been connected with increased soil strength and decreased aeration that are commonly remnants of site disturbances associated with wet-weather harvesting. A simple and economical rating system is needed to identify soils susceptible to disturbance by various types of equipment. The use of such a system could lower the impact on wetland soils and lower the cost of extensive site preparation methods. Logging efficiency and operational productivity could also be increased by identifying equipment types compatible with site conditions. The purpose of this study was to characterize and model soil strength as a function of soil physical properties and site characteristics. The soil strength model was subsequently used to develop a trafficability hazard index. Forested wetland sites in the South Carolina coastal plain were characterized to develop the trafficability hazard index. The study site consisted of three blocks located on poorly drained loblolly pine plantations. Five sequences of measurements were taken consisting of soil moisture, water table depth, and soil strength. The five sequences of measurements were taken over a wide range of soil moisture contents and water table depths to characterize the effects on soil strength. Bulk density, porosity, texture, organic matter, and hydraulic conductivity were also determined to characterize the blocks and identify effects on soil strength. Evaluating the effects of these properties on soil strength identified two relatively easily determined soil properties that could be used for the trafficability index. Volumetric moisture content and penetration resistance of the A horizon were used due to their relationships with trafficability and ease of determination. Estimates of pressure applied to the soil by harvesting equipment were used to find the limits of the sandy loam A horizon to support various types of equipment. Equipment pressures were compared to soil penetration resistance pressures estimated by soil moisture. The trafficability hazard index presented used general ground pressures for various harvesting equipment, but use of specific equipment pressures would provide the best results. Using the trafficability hazard index, sites with less than optimal conditions for traffic can be avoided or special harvesting equipment can be identified to limit site disturbance. / Master of Science

by Fung, Chun-hong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 111-123). / Abstract --- p.i / Acknowledgments --- p.iii / List of Tables --- p.v / List of Figures --- p.vii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Reforestation in Hong Kong --- p.1 / Chapter 1.2 --- Conceptual framework of the study --- p.2 / Chapter 1.3 --- Objectives of the study --- p.5 / Chapter 1.4 --- Significance of the study --- p.6 / Chapter 1.5 --- Organization of the thesis --- p.6 / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Vegetation and soils --- p.8 / Chapter 2.2 --- Trees and soil physical properties --- p.9 / Chapter 2.2.1 --- Aggregate stability --- p.9 / Chapter 2.2.2 --- Organic matter and aggregate stability --- p.10 / Chapter 2.2.3 --- Other factors affecting aggregate stability --- p.12 / Chapter 2.2.4 --- Reforestation and bulk density --- p.12 / Chapter 2.2.5 --- Reforestation and soil moisture --- p.13 / Chapter 2.3 --- Trees and soil chemical properties --- p.14 / Chapter 2.3.1 --- Exchangeable acidity --- p.14 / Chapter 2.3.2 --- Exchangeable acidity and cation exchange capacity --- p.15 / Chapter 2.3.3 --- Organic matter and cation exchange capacity --- p.15 / Chapter 2.3.4 --- Clay and cation exchange capacity --- p.16 / Chapter 2.3.5 --- Organic matter and nitrogen --- p.17 / Chapter 2.3.6 --- Organic matter and phosphorus --- p.18 / Chapter 2.4 --- Litter decomposition --- p.18 / Chapter 2.4.1 --- Factor affecting litter decomposition --- p.19 / Chapter 2.4.2 --- Effects of litter on soil nutrient reserve --- p.21 / Chapter Chapter 3 --- The Study Area / Chapter 3.1 --- Location --- p.23 / Chapter 3.2 --- Geology --- p.23 / Chapter 3.3 --- Soils --- p.25 / Chapter 3.4 --- Vegetation --- p.27 / Chapter 3.4.1 --- Reforestation since the mid-1980s --- p.27 / Chapter 3.4.2 --- Growth performance of the acacias --- p.28 / Chapter 3.4.3 --- Undergrowth of the acacia woodlands --- p.29 / Chapter Chapter 4 --- Effects on Soil Physical Properties / Chapter 4.1 --- Introduction --- p.31 / Chapter 4.2 --- Methodology --- p.33 / Chapter 4.2.1 --- Soil texture --- p.33 / Chapter 4.2.2 --- Bulk density and porosity --- p.33 / Chapter 4.2.3 --- Penetration resistance --- p.34 / Chapter 4.2.4 --- Aggregate stability --- p.34 / Chapter 4.2.5 --- Water characteristic curve --- p.35 / Chapter 4.2.6 --- Infiltration rate --- p.35 / Chapter 4.3 --- Statistical analysis --- p.35 / Chapter 4.4 --- Results --- p.36 / Chapter 4.4.1 --- Soil texture --- p.36 / Chapter 4.4.2 --- "Bulk density, porosity and penetration resistance" --- p.36 / Chapter 4.4.3 --- Aggregate stability --- p.38 / Chapter 4.4.4 --- Infiltration --- p.39 / Chapter 4.4.5 --- Water characteristic curve --- p.40 / Chapter 4.5 --- Discussion --- p.42 / Chapter 4.5.1 --- Inherent physical properties of granitic soil --- p.42 / Chapter 4.5.2 --- Effects of acacias on the aeration of granite soil --- p.44 / Chapter 4.5.3 --- Effects of acacias on the penetration resistance and aggregate stability of granitic soil --- p.46 / Chapter 4.5.4 --- Effects of acacias on the water transmission property of granitic soil --- p.47 / Chapter 4.5.5 --- Effects of acacias on the water retention property of granitic soil --- p.50 / Chapter 4.6 --- Conclusion --- p.52 / Chapter Chapter 5 --- Effects on Soil Chemical Properties / Chapter 5.1 --- Introduction --- p.54 / Chapter 5.2 --- Methodology --- p.55 / Chapter 5.2.1 --- Sampling --- p.55 / Chapter 5.2.2 --- Soil reaction and conductivity --- p.55 / Chapter 5.2.3 --- Organic carbon --- p.55 / Chapter 5.2.4 --- Total Kjeldahl nitrogen --- p.56 / Chapter 5.2.5 --- Total phosphorus --- p.56 / Chapter 5.2.6 --- "Exchangeable K, Ca, Mg and Na" --- p.56 / Chapter 5.2.7 --- Exchangeable A1 and H --- p.57 / Chapter 5.2.8 --- Carbon : nitrogen ratio --- p.57 / Chapter 5.3 --- Statistical analysis --- p.57 / Chapter 5.4 --- Results --- p.58 / Chapter 5.4.1 --- Conductivity --- p.58 / Chapter 5.4.2 --- Soil pH and exchangeable acidity --- p.58 / Chapter 5.4.3 --- Soil organic matter --- p.61 / Chapter 5.4.4 --- Total Kjeldahl nitrogen --- p.62 / Chapter 5.4.5 --- Total phosphorus --- p.63 / Chapter 5.4.6 --- "Exchangeable K, Ca, Mg and Na" --- p.64 / Chapter 5.5 --- Discussion --- p.67 / Chapter 5.5.1 --- Inherent chemical properties of granitic soil --- p.67 / Chapter 5.5.2 --- Effects of acacias on the acidity of granitic soil --- p.69 / Chapter 5.5.3 --- "Effects of acacias on the organic matter, total nitrogen and phosphorus of granitic soil" --- p.71 / Chapter 5.5.4 --- Effects of acacias on the exchangeable cations of granitic soil --- p.74 / Chapter 5.6 --- Conclusion --- p.76 / Chapter Chapter 6 --- Litter Decomposition / Chapter 6.1 --- Introduction --- p.78 / Chapter 6.2 --- Methodology --- p.79 / Chapter 6.2.1 --- Standing litter --- p.79 / Chapter 6.2.2 --- Litter decomposition --- p.80 / Chapter 6.2.3 --- Chemical analysis --- p.80 / Chapter 6.3 --- Statistical analysis --- p.81 / Chapter 6.4 --- Results --- p.81 / Chapter 6.4.1 --- Standing litter --- p.81 / Chapter 6.4.2 --- Chemical composition of fresh litters --- p.82 / Chapter 6.4.3 --- Cumulative dry weight loss of litters --- p.82 / Chapter 6.4.4 --- Cumulative weight loss of nutrients --- p.84 / Chapter 6.4.5 --- C : element ratios --- p.88 / Chapter 6.5 --- Discussion --- p.88 / Chapter 6.5.1 --- Litter decomposition --- p.88 / Chapter 6.5.2 --- Litter decomposition and soil organic matter --- p.93 / Chapter 6.5.3 --- Nutrient release patterns --- p.94 / Chapter 6 5 --- 4 Litter decomposition and soil nutrient reserves --- p.96 / Chapter 6.6 --- Conclusion --- p.98 / Chapter Chapter 7 --- Conclusion / Chapter 7.1 --- Summary of findings --- p.100 / Chapter 7.2 --- Implication of the study --- p.103 / Chapter 7.3 --- Limitations of the study --- p.106 / Chapter 7.4 --- Suggestion for future study --- p.108 / References --- p.111 / Appendice --- p.124

The biochar is a promissor product for the soil improvement as physical, chemical and hydraulic properties. However, there is a lack of information about the influence of biochar rate, particle size, depth, soil texture and time of interaction on tropical climate. This is one of the first studies that analyse these properties under tropical condition. The objective of this study was analyze the effect of biochar (BC) rate and particle size on soil chemical, physical and hydraulic properties on tropical condition. Was acessed the effect BC rate (6.25, 12.5 and 25 Mg ha-1) in Clay loam and sandy soil under laboratory condition on chemical properties (C, N and C/N ratio), physical properties (bulk density, porosity and pore size distribution) and hydraulic properties (water holding capacity and water available content). In field condition, the effect of the Filter cake (FC) and FC + BC rate (6.25, 12.5 and 25 Mg ha-1) was studied in two depth (0-10 and 10-20 cm) in two times of interaction (9 and 18 months) on soil physical (bulk density, porosity and pore size distribution and aggregate stability) and hydraulic properties (water holding capacity and water available content and hydraulic conductivity). To verify the best BC particle size to be applied on the soil, a third study was developed to test the effect of BC particle size (< 0.15; 0.15-2 and > 2mm) in clay loam and sandy soil and to analyze its effects on soil chemical, physical and hydraulic properties. In the first study (effect of BC rate on laboratory condition) a positive effect of BC rate on water availability, microporosity, and on water retention was found, especially for clay loam soil at high BC application, but this influence did not occur for sandy soil, possibly due to the short time of interaction. In the second study (effect of BC rate and FC on physical, chemical and hydraulic properties) the bulk density slightly decreased, and the porosity increased after nine months of interaction upon FC + BC 25 Mg ha-1. However, after 18 months, the FC + BC amount altered the pore size distribution with an increase of micropores, aggregate stability, available water content and its alteration was dependent on the FC + BC rate. Nevertheless, this effect was not verified in the hydraulic conductivity (Kfs). The time of interaction contributes to increasing the Kfs, and the reduction of Kfs was found with the increase of FC + biochar rate, especially in higher amount FC + BC (25 Mg ha-1) of biochar. In the third work (effect of biochar particle size on chemical and physical and hydraulic properties) total carbon content increased mainly in sandy soil compared to control treatment, the highest carbon amount was obtained in the biochar size 0.15-2 mm in loamy soil and < 0.15 mm in sandy soil, while TN content and C/N ratio increased slightly with reduction of the biochar particle size in both soils. These results demonstrated that biochar particle size is crucial for water retention, water availability, pore size distribution and C sequestration. It is evident that is possible to save irrigation water and improve soil chemical and physical properties by applying biochar. / O biocarvão (BC) é um produto promissor para a melhoria da qualidade química, física, e hidráulica do solo. No entanto, faltam estudos sobre a influência da dose de BC, tamanho de partícula, profundidade de aplicação, efeitos sobre a textura do solo e tempo de interação em condições de clima tropical. Este é um dos primeiros trabalhos que avaliam essas propriedades em solos sob condições tropicais. O objetivo deste estudo foi analisar o efeito da dose de BC e do tamanho de partículas nas propriedades químicas, físicas e hidráulicas do solo em condição tropical. Avaliou-se o efeito da dose de BC (6,25; 12,5 e 25 Mg ha-1) em solo franco argiloso e arenoso, em condições de laboratório sobre as propriedades químicas (C, N e C/N), físicas (densidade do solo, porosidade e distribuição do tamanho dos poros) e hidráulicas do solo (capacidade de retenção de água e teor de água disponível). Em condição de campo foi estudado o efeito da torta de filtro e dose de BC (6,25, 12,5 e 25 Mg ha-1) mais torta de filtro (TF) em duas profundidades (0-10 e 10-20 cm) e em dois tempos de interação (9 e 18 meses) sobre as propriedades físicas (densidade do solo, porosidade, distribuição do tamanho dos poros e estabilidade de agregados) e hidráulicas do solo (capacidade de retenção de água, teor de água disponível e condutividade hidráulica). A fim de verificar o melhor tamanho de partícula de BC a ser aplicado ao solo foi desenvolvido um terceiro estudo no qual foi avaliado o efeito do tamanho de partículas de BC (< 0,15; 0,15-2 e > 2mm) em solo franco argiloso e arenoso sobre as mesmas propriedades químicas, físicas e hidráulicas do solo avaliadas no primeiro estudo. No estudo da influência de dose de BC em condição de laboratório, foi verificado efeito positivo da dose de BC na disponibilidade de água, microporosidade e retenção de água, especialmente para solo franco argiloso com alta aplicação de BC, mas essa influência não ocorreu, para solos arenosos, possivelmente devido ao curto período de interação. No segundo estudo (efeito da dose de BC+TF) verificou-se que a densidade diminuiu ligeiramente e a porosidade aumentou após nove meses de interação com TF + BC 25 Mg ha-1 e após 18 meses, a quantidade de BC+TF alterou a distribuição do tamanho dos poros aumentando a quantidade de microporos, melhorando a estabilidade do agregado e o conteúdo de água disponível (CAD). O efeito da dose não foi verificado para condutividade hidráulica (Kfs), porém o tempo de interação contribuiu para aumentar os Kfs. Além disso, uma redução de Kfs foi encontrada com o aumento da taxa de BC + TF, especialmente na maior quantidade de TF + BC (25 Mg ha-1) de biocarvão. No terceiro estudo, (efeito do tamanho das partículas de BC nas propriedades químicas, físicas e hidráulicas), o teor total de carbono aumentou principalmente em solo arenoso comparado ao tratamento controle, a maior quantidade de carbono foi obtida no tamanho do BC 0,15-2 mm em solo argiloso e < 0,15 mm em solo arenoso, enquanto o teor de TN e a relação C/N aumentaram ligeiramente com a redução do tamanho das partículas de BC em ambos os solos. Estes resultados demonstraram que o tamanho das partículas de BC é crucial para a retenção, disponibilidade de água, distribuição de tamanho de poros e sequestro de carbono. Esses estudos demonstraram que é possível economizar água de irrigação e melhorar as propriedades químicas e físicas do solo por meio da aplicação do biocarvão.

Neste trabalho, é apresentado um novo modelo de reconstrução tridimensional (3D) para amostras agrícolas com filtragem de Wiener em processamento paralelo, o qual é obtido a partir de reconstruções tomográficas bidimensionais (2D). No desenvolvimento, foram modelados algoritmos paralelos de retroprojeção filtrada e reconstrução tridimensional, baseando-se na inserção de um conjunto de planos virtuais entre pares de planos reais obtidos em ensaios tomográficos de raios X na faixa de energia de 56 keV a 662 keV. No modelo, os planos virtuais gerados em algoritmo paralelo são implementados com base na técnica de interpolação por B-Spline-Wavelet. Para validação do modelo desenvolvido, foi utilizada uma plataforma paralela composta de 4 processadores DSP, a qual possibilitou a troca de dados entre os processadores DSP e o envio de informações para o host, um computador desktop com processador Pentium III operando em 800 MHz. A extração de medidas de eficiência, de ganho e de precisão dos algoritmos paralelos foi realizada com base em um conjunto de amostras agrícolas (solo, vidro e madeiras) e de phantoms de calibração. Nessa avaliação, observou-se que o algoritmo de reconstrução 2D, utilizado como base para o algoritmo de reconstrução 3D, possibilitou uma alta eficiência para imagens de maior resolução, atingindo um pico de 92% de eficiência na resolução de 181X181 pixels. O algoritmo paralelo de reconstrução 3D foi analisado para um conjunto de amostras, sob diferentes configurações de planos reais e virtuais, organizados de forma a possibilitarem a avaliação do impacto causado pelo aumento da granularidade da comunicação e da carga de trabalho. Um melhor desempenho, com ganho médio igual a 3,4, foi obtido na reconstrução de objetos que demandaram o cálculo de um maior número de planos. Também, buscou-se conhecer a adaptabilidade do modelo para uso em arquitetura convencional, sendo que neste caso o uso de MPI permitiu a comunicação entre as tarefas projetadas em cada algoritmo paralelo. Adicionamente, foram incluídas ferramentas de visualização 2D e 3D para que usuários possam analisar as imagens e as características das amostras agrícolas em ambiente tridimensional. Os resultados obtidos indicam que o modelo de reconstrução 3D paralela trouxe contribuições originais para a área de tomografia agrícola aplicada à física de solos, bem como para a criação de ferramentas que viabilizem explorar recursos computacionais disponíveis em arquiteturas paralelas que demandem elevada capacidade de processamento. / This work presents a new method for three dimensional (3D) image reconstruction dedicated to the investigation in soil physics by means of X-ray tomography which is obtained using two-dimensional (2D) tomographic image reconstructed slices. The conception of the 3D model for reconstruction and visualization was based on the filtered back projection algorithm, operating under parallel environment together the insertion of virtual planes between pairs of real planes obtained by X-Ray tomography under energies varying from 56 keV to 662 keV. In this model, the virtual planes were generated by interpolation with the use of B-Spline-Wavelets. The evaluation of the 3D reconstruction model was established by using a set of agricultural samples (i.e., soil, glass, wood and calibration phantoms) having different configuration for the planes. Such configuration was based on setting not only the sizes and the number of the real but also the virtual planes in the volume. This procedure allows the impact measurements as a function of the increasing in workload and the communication granularity. To validate the reconstruction model, a dedicated parallel architecture composed of 4 DSP processors was used. This board enables data exchange between DSP processors and communication with host computer. A measurement of efficiency with a speed up equal to 3.4 was obtained using the same set of samples and a better performance was observed with a higher number of planes. Also, to understand about its adaptability, the model was implemented in conventional architecture, using MPI library to enable communication between designed tasks. Additionally, 2D and 3D visualization tools based on Vizualization ToolKit were included in order to help users to analyze images and their characteristics. Results have shown that the 3D parallel model reconstruction brought original contributions for the soil science diagnosis by X-Ray tomography, as well as to explore the available computational resources in parallel architectures, which demands great processing capacity.