A presente pesquisa teve por objetivo demonstrar quais processos pedogenéticos ocorrem na gênese e evolução de solos no setor noroeste do Estado do Paraná, mais especificamente a evolução de horizontes B níticos sobre B latossólicos em uma área de basaltos inseridos na faixa de transição litológica arenitos-basaltos deste setor do estado. A área de estudos é a bacia hidrográfica do córrego Gurupá, no município de Floraí/PR. Utilizamos técnicas e procedimentos de fotointerpretação para levantamento geológico com o objetivo de elucidar a distribuição do substrato, formas de relevo e solos associados, elaborando como produto final um Mapa Morfolitológico. Para a análise multiescalar da organização e dinâmica da cobertura pedológica utilizamos procedimentos propostos pela Análise Estrutural da Cobertura Pedológica. O sistema pedológico estudado apresenta um volume superficial arenoso e volumes subsuperficiais mais argilosos, com organizações em blocos poliédricos ou microagregados, bem distinguíveis em campo; a análise dos parâmetros físicos e químicos demonstrou uma diferenciação morfológica dos grãos de quartzo em profundidade e concentração heterogênea de elementos e óxidos nos perfis estudados. Com o auxílio de conceitos, técnicas e procedimentos da micromorfologia de solos, demonstramos que na área de estudos ocorre uma intensa dissolução geoquímica de grãos de quartzo, sob a forma de golfos de dissolução, separações plásmicas mais abundantes no contato entre os volumes arenoso e argiloso, com evolução em profundidade, e intensa acumulação de argila iluviada em subsuperfície, provocando reorganizações de núcleos microagregados em blocos poliédricos, com evolução ascendente. Em síntese, este sistema evolui em decorrência do transporte de matéria que promove reorganizações no interior da cobertura pedológica (processo de eluviação-iluviação), indicando que a área passa por um período de desequilíbrio pedobioclimático. / The goal of the present research is to show which pedogenetic processes take place in the genesis and evolution of soils in the northwest of the state of Paraná, aiming specifically on the formation of nitic horizons on top of latosolic horizons in a basaltic area, inserted in a lithological transition zone, between basalts and sandstones. The study area is the Gurupá Creek hydrographical basin, located in Floraí - PR. In this process, photointerpretation techniques and procedures were used for the geological survey, in order to elucidate the substratum´s distribution, landforms and associated soils. The final cartographic product is a Morpholithological Map. The Structural Analysis of the Pedological Coverage supplied us with the procedures which allowed the multi-scalar analysis of the organization and dynamics of the soil coverage. The pedological system studied in this research presents a sandy superficial volume, and an increase in clay content in the subsuperficial volumes, organized in polyhedral blocks or microaggregated structure, clearly distinguishable during the field work; the analysis of the physical and chemical parameters revealed a morphological difference between the quartz grains in depth and heterogeneous concentration of elements and oxides in the studied profiles. With the support of different concepts, techniques and procedures of soil micromorphology, we demonstrated that an intense geochemical dissolution of the quartz grains is currently taking place, in the form of dissolution gulfs, abundant plasmic separations in the contact of the sandy and argilic volumes, with an evolution in depth and intense illuviated clay accumulation in the subsurface, causing the reorganization of the microaggregated structure in polyhedral blocks, with an ascending evolution. In synthesis, this system evolves through the transportation of matter, which promotes reorganizations within the pedological coverage (elluviation/illuviation), indicating that the area is going through a period of pedobioclimatic imbalance.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Geological remote sensing is a powerful tool for lithological discrimination, especially in arid regions with minimal vegetative cover to obscure rock exposures. Commercial multispectral imaging satellites provide a broad spectral range with which to target specific rock types. Landsat ETM+ (7), ASTER, and SPOT 5 multispectral images were acquired and digitally processed: band ratioing, principle components analysis, and maximum likelihood supervised classification. The sensors were evaluated on the ability to discriminate between sedimentary rocks in a structurally complex setting. The study focusses on the formations of the Naukluft Nappe Complex, Namibia. Previous work of the area had to be consulted in order to identify the main target rock types. Dolomite, limestone, quartzite, and shale were determined to make up the majority of rock types in the area. Landsat, ASTER, and SPOT 5 imagery were acquired and pre-processed. Each was subjected to transform techniques: band ratios and PCA. Band ratios were tailored to highlighted target rock types as well as a number of control ratios to ensure the integrity of important ratios. PCA components were inspected to find the most useful ones which were combined into FCCs. Transform results, expert knowledge, and a geological map were consulted to identify training and accuracy samples for the supervised classifications. All three classifications made use of the same set of training and accuracy samples to facilitate useful comparisons. Transform results were promising for Landsat and ASTER images, while SPOT 5 struggled. The limited spectral resolution of SPOT 5 limited its use for identifying target rock types, with the superior spatial resolution contributing very little. Landsat benefitted from good spectral resolution. This allowed for good performance with highlighting limestone and dolomite, while being less successful with shale. Quartzite was a real problem as the spectral resolution of Landsat could not cover this range as well. ASTER, having the highest spectral resolution, could distinguish between all four target rock types. Landsat and ASTER results suffered in areas where formations were relatively thin (smaller than sensor spatial resolution). The supervised classification results were similar to the transforms in that both Landsat and ASTER provided useful results, while SPOT 5 failed to yield definitive results. Accuracy assessment determined that ASTER performed the best at 98.72%. Landsat produced an accuracy of 93.29% while SPOT 5 was 80.17% accuracy. Landsat completely overestimated the amount of quartzite present, while all results classified significant proportions Quaternary sediments as shale. Limestone was well represented in even the poorest results, while dolomite usually struggled in areas where it was in close association with quartzite. Silica yields relatively strong responses in the TIR spectrum which could lead to misclassification of dolomite, which also has strong TIR signatures. / AFRIKAANSE OPSOMMING: Geologiese afstandswaarneming is 'n kragtige tegniek vir litologiese diskriminasie, veral in droë streke met minimale plantbedekking om dagsome te verduister. Kommersiële multispektrale satelliete beelde bied 'n breë spektrale reeks waarmee spesifieke gesteentetipes geteiken kan word. Landsat ETM + (7), ASTER, en SPOT 5 multispektrale beelde was bekom en digitaal verwerk: bandverhoudings, hoofkomponente-ontleding, en maksimum waarskynlikheid klassifikasie. Die sensors is geëvalueer op hul vermoë om te onderskei tussen sedimentêre gesteentes in 'n struktureel komplekse omgewing. Die studie fokus op die formasies van die Naukluft Dekblad Kompleks, Namibië. Vorige werk van die area was geraadpleeg om die hoofgesteentetipes te identifiseer. Dit was bepaal dat dolomiet, kalksteen, kwartsiet, en skalie die oorgrote meerderheid van kliptipes in area opgemaak het. Landsat, ASTER, en SPOT 5 beelde is verkry en voorverwerk. Elke beeld was onderwerp aan transformasietegnieke: bandverhoudings en hoofkomponente-ontleding. Bandverhoudings is aangepas om teiken rotstipes uit te lig asook 'n aantal kontrole bandverhoudings om die integriteit van belangrike verhoudings te verseker. Hoofkomponente-ontleding komponente is ondersoek om die mees bruikbares te vind en dié was gekombineer in valse kleur samestellings. Transformasie resultate, deskundige kennis, en 'n geologiese kaart was geraadpleeg om opleidings- en verwysingsmonsters was verkry vanaf die beelde vir die klassifikasies. Al drie klassifikasies gebruik gemaak van dieselfde stel van die opleiding- en akkuraatheidsmonsters om sodoende betekenisvolle vergelykings te verseker. Transformasie resultate is belowend vir Landsat en ASTER beelde, terwyl SPOT 5 minder bruikbaar was. Die noue spektrale resolusie van SPOT 5 beperk die gebruik daarvan vir die identifisering van teiken gesteentetipes terwyl die hoë ruimtelike resolusie baie min bydra. Landsat het voordeel getrek uit goeie spektrale resolusie. Dit goeie resultate opgelwer met die klem op kalksteen en dolomiet, terwyl skalie aansienlik swakker resultate opgelewer het. Kwartsiet was 'n werklike probleem omdat die spektrale resolusie van Landsat nie breed genoeg was om hierdie kliptipe te onderskei nie. ASTER, met die hoogste spektrale resolusie, kon onderskei tussen al vier teiken rotstipes. Landsat en ASTER resultate was baie negatief beïnvloed in gebiede waar formasies relatief dun was (kleiner as sensor ruimtelike resolusie). Die klassifikasie resultate was soortgelyk aan die transformasies in dat beide Landsat en ASTER nuttige resultate opgelewer het, terwyl SPOT 5 misluk het. Akkuraatheids assessering het bepaal dat ASTER die beste gevaar het met 98,72%. Landsat het 'n akkuraatheid van 93,29% opgelewer, terwyl SPOT 5 80,17% akkuraat was. Landsat het die hoeveelheid kwartsiet heeltemal oorskat, terwyl al die resultate groot hoeveelhede Kwaternêre sedimente as skalie geklassifiseer het. Kalksteen is goed verteenwoordig in tot die armste resultate, terwyl resultate gewoonlik afgeneem het waar dolomiet in noue verband met kwartsiet was. Dit is moontlik asgevolg van silika se relatiewe sterk reaksies in die termiese infra-rooi spektrum wat kan lei tot die foutiewe klassifisering met dolomiet (wat ook sterk reageer in die TIR spektrum).

La compréhension des écoulements préférentiels dans la zone non saturée en fond de bassins d’infiltration est une condition préalable à une gestion optimale de ces ouvrages. Le basin d’infiltration étudié repose sur un dépôt fluvioglaciaire hétérogène constitué d’un lithofaciès majoritaire contenant des lentilles de sable et de gravier. Une étude géophysique (radar) a permis de caractériser cette hétérogénéité sédimentologique le long de radar-grammes (sections de quelques mètres de profondeurs et de plusieurs dizaines de mètre de long). Les écoulements ont été modélisés pour toutes ces sections ainsi qu’une section fictive remplie uniquement du lithofaciès majoritaire (témoin) et pour divers évènements pluvieux type incluant une chronique météorologique complète. Les résultats montrent clairement que l'hétérogénéité lithologique a un effet significatif sur l’écoulement avec la mise en place d’écoulements hétérogènes du fait de phénomènes de barrière capillaire au niveau des lentilles de sable et de gravier en non-saturé. Cet effet se répercute sur les chemins de l’eau dans le dépôt et sur les flux en surface (infiltration et ruissellement). Les résultats montrent aussi que cet effet dépend fortement de la section considérée. La variabilité spatiale de l’hétérogénéité lithologique induit donc une variabilité spatiale des écoulements préférentiels. Certains paramètres architecturaux et géométriques relatifs à l’hétérogénéité lithologique ont été proposés pour expliquer l’effet de l’hétérogénéité lithologique sur les écoulements préférentiels, de sorte à proposer une première tentative de modélisation des écoulements à méso-échelle. / Understanding preferential flows in the vadose zone is a prerequisite for a proper management of infiltration basins. The studied infiltration basin lies on a strongly heterogeneous glaciofluvial deposit made of a predominant lithofacies that embeds lenses of sand and gravel. Geophysics (GPR) were used to characterize the lithological heterogeneity along radar-grammes (sections few meters deep and dozens of meters long). Flow was modelled for all these sections and compared to a synthetic section filled only with the predominant lithofacies (control). Numerical results show that, under unsaturated conditions, the lithological heterogeneity has a strong impact on flow with the establishment of preferential flows induced by capillary-barrier effects in the vicinity of lenses of sand and gravel. These effects have also consequences on water fluxes at surface (infiltration and runoff) and depend strongly on the section considered for numerical modelling. It can thus be concluded that the spatial variability of lithological heterogeneity induces a spatial variability of preferential flow. Geometrical and architectural parameters were defined to quantity lithological heterogeneity and link it to preferential flows, with the aim to propose a first step towards modelling flow in the basin at the meso-scale. / O entendimento do fluxo na zona não saturada em formações heterogêneas é um prérequisito para uma gestão adequada de poluentes em bacias de infiltração inseridas nessas formações. Este estudo aborda o efeito da heterogeneidade litológica nos processo de escoamento numa bacia de infiltração com geologia inserida num depósito fluvioglacial. A bacia de infiltração é a Bacia Django Reinhardt, existente em Lyon. Esta bacia foi objeto de vários estudos que demonstraram algumas avaliações do impacto da heterogeneidade do solo. Os objetivos desses trabalhos foram todos baseados apenas no estudo sedimentológico de uma trincheira. Nenhum estudo abordou a potencial variabilidade espacial dos atributos do solo. Neste trabalho, foi modelizado o fluxo na zona vadosa através de três casos: drenagem interna, infiltração de água durante um evento de precipitação pluviométrica constante e solicitação hidrológica a partir de um fluxo variável escoamento superficial. Estes cálculos foram realizados para várias seções, que foram previamente caracterizadas quanto a sua heterogeneidade estrutural usando a técnica não destrutiva do GPR com uma frequência de 200MHz e 100MHz. O comportamento hidráulico dessas seções foi comparado com a de uma seção homogênea. Foi comparada o efeito da resolução da imagem nas estimativas das variáveis de fluxo. Alguns indicadores arquiteturais, geométricos e texturais foram propostos para esclarecer e avaliar a variabilidade espacial do efeito da heterogeneidade do solo sobre o fluxo em condições não saturadas. Os resultados mostram claramente que a heterogeneidade gera impactos nas variáveis de fluxo em condições não saturadas. Os impactos dependem da seção considerada.Os resultados mostram também que: a) a heterogeneidade estrutural do subsolo na meso-escala apresenta um efeito sobre a geração de escoamento preferencial e isso independe do tipo de solicitação aplicada na seção; b) O efeito da heterogeneidade se mostrou independentende das condições de contorno aplicadas na superfície; c) Nos períodos de ocorrência de chuvas intensas quem controla o comportamento das variáveis de fluxo é a intensidade de precipitação. No entanto, nos períodos em que ocorre ausência de precipitação, as variáveis de fluxo são controladas pela heterogeneidade da zona não saturada; d) A utilização de diferentes frequências influencia na estimativa das variáveis de fluxo. Isso é decorrente do impacto na quantificação da heterogeneidade decorrente do efeito da resolução de cada antena; e) Os indicadores não apresentaram relação direta com as variáveis de fluxo estudadas. Isso demonstra que o efeito da heterogeneidade não pode ser explicado por um único fator, mas por um conjunto de fatores.