This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley's K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Trajectories of the LDMs for the cross faults around each caldera define asymmetric sub-parabolic patterns similar to the reported parabolic distribution of the epicenters, and indicate sub-elliptical extension about each caldera that may mark the shape of hotspot’s thermal doming that formed each generation of cross faults. The decrease in the spatial density of the CFs as a function of distance from the axis of the track of the hotspot (SRP) also suggests the role of the hotspot for the formation of the cross faults. The parallelism of the trend of the exposures of the graben filling Sixmile Creek Formation with the LDM of their bounding cross faults indicates that the grabens were filled during or after the CF event. The global and local Moran’s I analyses of Neogene lava in each caldera along the SRP reveal a higher spatial autocorrelation and clustering of rhyolitic lava than the coeval basaltic lava in the same caldera. The alignment of the major axis of the standard deviational ellipses of lavas with the trend of the eastern SRP, and the successive spatial overlap of older lavas by progressively younger mafic lava, indicate the migration of the centers of eruption as the hotspot moved to the northeast.

Διάφορες κλιματολογικές, υδρολογικές και περιβαλλοντικές μελέτες απαιτούν ακριβή γνώση της χωρικής κατανομής των σταθερών ισοτόπων του υδρογόνου και του οξυγόνου στον υετό. Δεδομένου ότι ο αριθμός των σταθμών συλλογής δειγμάτων υετού για ισοτοπική ανάλυση είναι μικρός και όχι ομογενώς κατανεμημένος σε πλανητικό επίπεδο, η πλανητκή κατανομή των σταθερών ισοτόπων μπορεί να υπολογισθεί μέσω της δημιουργίας πλεγματικών ισοτοπικών δεδομένων, για τη δημιουργία των οποίων έχουν προταθεί διάφορες μέθοδοι. Ορισμένες χρησιμοποιούν εμπειρικές σχέσεις και γεωστατιστικές μεθόδους ώστε να ελαχιστοποιήσουν τα σφάλματα λόγω παρεμβολής. Στην εργασία αυτή γίνεται μια προσπάθεια να δημιουργηθούν βάσεις πλεγματικών δεδομένων της ισοτοπικής σύστασης του υετού με ανάλυση 10΄ × 10΄ για την περιοχή της Κεντρικής και Ανατολικής Μεσογείου. Προσδιορίζονται στατιστικά πρότυπα λαμβάνοντας υπ’ όψιν γεωγραφικές και μετεωρολογικές παραμέτρους, ως ανεξάρτητες μεταβλητές. Η αρχική μεθοδολογία χρησιμοποιεί μόνο το υψόμετρο της περιοχής και το γεωγραφικό της πλάτος ως ανεξάρτητες μεταβλητές. Επειδή η ισοτοπική σύσταση εξαρτάται και από το γεωγραφικό μήκος προστέθηκαν στα υφιστάμενα πρότυπα, εκτός των γεωγραφικών μεταβλητών και μετεωρολογικές. Προτείνεται σειρά προτύπων τα οποία περιλαμβάνουν είτε ορισμένες είτε συνδυασμό αυτών των παραμέτρων. Η αξιολόγηση των προτύπων γίνεται με εφαρμογή των μεθόδων Thin Plate Splines (TPSS) και Ordinary Kriging (ΟΚ). / Several climatic, hydrological and environmental studies require the accurate knowledge of the spatial distribution of stable isotopes in precipitation. Since the number of rain sampling stations for isotope analysis is small and not evenly distributed around the globe, the global distribution of stable isotopes can be calculated via the production of gridded isotopic data sets. Several methods have been proposed for this purpose. Some of them use empirical equations and geostatistical methods in order to minimize eventual errors due to interpolation. In this work a methodology is proposed for the development of 10΄ × 10΄ gridded isotopic data of precipitation in Central and Eastern Mediterranean. Statistical models are developed taking into account geographical and meteorological parameters as independent variables. The initial methodology takes into account only the altitude and latitude of an area. Since however the isotopic composition of precipitation depends also on longitude, the existing models have been modified by adding meteorological parameters as independent variables also. A series of models is proposed taking into account some or a combination of the above mentioned variables. The models are validated using the Thin Plate Smoothing Splines (TPSS) and the Ordinary Kriging (OK) methods.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-06T15:15:51Z No. of bitstreams: 1 PGEF16MA055.pdf: 2636965 bytes, checksum: 1227c615c043f057d8dbc346cd119e1f (MD5) / Made available in DSpace on 2017-12-06T15:15:51Z (GMT). No. of bitstreams: 1 PGEF16MA055.pdf: 2636965 bytes, checksum: 1227c615c043f057d8dbc346cd119e1f (MD5) Previous issue date: 2016-02-19 / FAPESC / The objective of this study was used the geostatistics and dendrochronology together with morphometric variables and dendrometric for, based on the diameter increment, evaluate the growth in Araucaria angustifolia in southern Brazil, adjust growth models and generate mapping the distribution the increase for landscape management aimed at sustainable interventions in its ecosystem. Data were collected in native forest fragments in four areas distributed in three municipalities in the mountainous plateau of Santa Catarina: São Joaquim, Urupema and Panel. Were sampled 256 trees, which gathered up the dendrometric and morphometric variables, as well as its position in space. The morphometric analysis index indicated that the species is different degrees of competition. Covariance analysis showed no difference in the shape-size ratio in sample areas. The crown insertion height correlated positively and better fit with the overall height, and negatively correlated with the proportion of canopy. The negative correlation with pc% indicates that a higher percentage of canopy corresponding to minor hic. The relationship between the proportion of crown according to the canopy trees with length indicates that greater length cup mantle and have a higher proportion of canopy thus improved growth capacity. For the crown diameter according to the diameter at breast height it was a positive correlation, that is, with the increase in size increases with the diameter of the crown. Interdimensional relationships analyzed by covariance showed differences between growing trees in the forest and free growth. growing trees without competition have greater and greater pc% cc than trees growing in competition, as well as have higher DC than on growth in the forest. It was possible to determine the potential crown diameter, growth space, the number of trees per hectare and basal area per hectare, serving as a resource for future interventions of forest management. For the analysis of increment in diameter and the age, we used the trunk partial analysis. In São Joaquim 1 the average for the mean annual increment in diameter was 0, 45 cm.ano-1 in São Joaquim 2, was 0,69 cm.ano-1, Urupema, 0,82 cm.ano- 1 and Painel, 0,94 cm.ano-1. Covariance analysis showed no differences in the average annual increase in the study sites. The incremental adjustment in the diameter at breast height and age showed that the trees showed a gradual decrease in the increase with increase in diameter and advancing age. Pearson correlation analysis for the annual periodic increment in basal area with morphometric variables and dendrometric showed that the variables with the highest correlation were proportion of cup and diameter, with a positive correlation value of 0,40 and 0,30. The generalized linear model Gamma - identity presented the best statistical criteria in setting annual periodic increment in basal area by diameter, percentage of canopy and height. The use of cup dimensions variables can be inserted in the modeling of the annual periodic increment in basal area of Araucaria angustifolia. In geostatistical analysis initially evaluated the data from classical statistics, then proceeded to the adjustment of the semivariogram. Later, we used the ordinary kriging for the interpolation of data. The standard deviation values show that there is greater variability in the panel data. There is a positive skew for all data, making it necessary to be transformed in some cases. The exponential model demonstrated better adjustment to the areas of São Joaquin and Painel already in Urupema the best model resulted in the spherical model. With the data interpolation maps was possible to visualize the spatial distribution of mean annual increment in diameter covered the four sites, identifying the areas with the highest and lowest diameter increment. The results generated in this study can understand the structure and growth of distribution Araucaria in each study site, to facilitate the management of the landscape and the species in southern Brazil. Current legislation restricts the sustainable use of the species, its natural regeneration and the increase in the rates, so reforms are needed in the legislation to ensure the perpetuity of the type Araucaria Forest / O objetivo do presente trabalho foi utilizar a geoestatística e a dendrocronologia em conjunto com as variáveis morfométricas e dendrométricas para, com base no incremento diamétrico, avaliar o crescimento no tempo de Araucaria angustifolia no sul do Brasil, ajustar modelos de crescimento e gerar mapas da distribuição do incremento para manejo da paisagem visando intervenções sustentadas em seu ecossistema. Os dados foram coletados em fragmentos de floresta nativa, em quatro áreas distribuídas em três municípios do planalto serrano de Santa Catarina: São Joaquim, Urupema e Painel. Foram amostradas 256 árvores, das quais coletou-se as variáveis dendrométricas e morfométricas, como também seu posicionamento no espaço. A análise dos índices morfométricos indicou que a espécie encontra-se em diferentes graus de competição. A análise de covariância demonstrou que há diferença na relação forma-dimensão nas áreas de amostragem. A altura de inserção de copa apresentou correlação positiva e melhor ajuste com a altura total, e correlação negativa com a proporção de copa. A correlação negativa com pc% indica que um maior percentual de copa corresponde a menor hic. A relação entre a proporção de copa em função do comprimento de copa indica que árvores com maior comprimento de copa apresentam maior manto e proporção de copa, consequentemente, melhor capacidade de crescimento. Para o diâmetro de copa em função do diâmetro à altura do peito a correlação foi positiva, ou seja, com o aumento em dimensão aumenta proporcionalmente o diâmetro de copa. As relações interdimensionais, analisadas pela covariância, demonstraram diferenças entre árvores de crescimento na floresta e de crescimento livre. Árvores crescendo sem competição apresentam maior pc% e maior cc do que árvores crescendo em competição, assim como, apresentam maior dc do que sob crescimento no interior da floresta. Foi possível determinar o diâmetro de copa potencial, o espaço de crescimento, o número de árvores por hectare e área basal por hectare, servindo como subsídio para futuras intervenções de manejo florestal. Para a análise do incremento em diâmetro e da idade, utilizou-se da análise parcial de tronco. Em São Joaquim 1 a média para o incremento médio anual em diâmetro foi de 0,45 cm.ano-1, em São Joaquim 2, foi de 0,69 cm.ano-1, em Urupema, 0,82 cm.ano-1 e em Painel, 0,94 cm.ano-1. A análise de covariância mostrou existir diferenças no incremento médio anual nos sítios de estudo. O ajuste do incremento em função do diâmetro à altura do peito e da idade mostrou que as árvores apresentaram diminuição gradativa do incremento com aumento do diâmetro e avanço da idade. A análise de correlação de Pearson para o incremento periódico anual em área basal com as variáveis morfométricas e dendrométricas, demonstrou que as variáveis com maior correlação foram proporção de copa e diâmetro, com correlação positiva de valor 0,40 e 0,30. O modelo linear generalizado Gamma - identidade apresentou os melhores critérios estatísticos no ajuste do incremento periódico anual em área basal em função do diâmetro, percentual de copa e altura. O uso de variáveis de dimensões da copa, podem ser inseridas na modelagem do incremento periódico anual em área basal de Araucaria angustifolia. Na análise geoestatística inicialmente avaliou-se os dados a partir da estatística clássica, em seguida procedeu-se o ajuste dos semivariogramas. Posteriormente, utilizou-se da Krigagem ordinária para a interpolação dos dados. Os valores do desvio padrão mostram que há maior variabilidade nos dados de Painel. Existe uma assimetria positiva para todos os dados, tornando necessária a transformação dos mesmos em alguns casos. O modelo exponencial demostrou melhor ajuste para as áreas de São Joaquim e Painel, já em Urupema o melhor modelo resultou no modelo esférico. Com os mapas de interpolação dos dados foi possível visualizar a distribuição espacial do incremento médio anual em diâmetro nos quatro sítios abordados, identificando as áreas com maior e menor incremento em diâmetro. Os resultados gerados neste trabalho possibilitam perceber a estrutura e a distribuição de crescimento da araucária em cada sítio de estudo, contribuindo para o manejo da paisagem e da espécie no sul do Brasil. A legislação atual restringe o uso sustentável da espécie, sua regeneração natural e o aumento nas taxas de incremento, assim, são necessárias reformas na legislação vigente para garantir a perpetuidade da tipologia Floresta com Araucária

Made available in DSpace on 2015-03-26T13:28:26Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3330909 bytes, checksum: 83d789ab10722b6666725f8fd263d49e (MD5) Previous issue date: 2013-10-07 / Fundação Instituto Brasileiro de Geografia e Estatística / In the process of production cartographic is natural the pursuit of quality spatial dataset. Throughout time technological evolution provided at the professionals in the area a constant growth in this production and in demand of these geospatial information by the users. However, to support this evolution without losing the qualification of space data is necessary to adopt standards. Furthermore, the complexity of geographic information in many aspects, require sampling techniques to measure and assess the quality of the spatial dataset in order to ensure with statistical basis, a significant amount and an appropriate spatial distribution of its samples. In Geosciences is intuitive to think in spatial correlation of a phenomenon under study and Geostatistics provides tools to identify and represent the behavior of this dependence. The spatial analysis of results from an inspection of a quality cartographic product is seldom addressed in literature, restricted only to conclusions descriptive and tabular, based on the assumption of classical statistical of independence from the observed data. At the present time is in deploying the National Spatial Data Infrastructure of Brazil (INDE), where several cartographic products are made available to the society, along with their geographic metadata. The metadata facilitates access to spatial data, but serve partly aspects concerning the quality of the dataset. Therefore, this thesis proposes a methodology for the quality inspection of spatial datasets of the INDE, based on international standards, concepts of generalization and elements of quality defined in literature as well as the spatial analysis of results of this inspection by using geostatistical methods and the representation of this assessment by means of quality maps. The method of quality evaluation data developed and applied on the Base Cartographic Continuous of Brazil at the 1:250.000 scale - BC250 with a focus on certain aspects of quality. The quality maps generated showed regionalizations in the indicators of quality inspected, confirmed by the staff that producer of cartographic base, subsidizing the producers themselves and users in understanding the spatial behavior quality product cartographic under study. / No processo de produção cartográfica é natural a busca pela qualidade do conjunto de dados espaciais. Ao longo do tempo, a evolução tecnológica propiciou aos profissionais da área um crescimento constante desta produção e na demanda destas informações geoespaciais por parte dos usuários. Entretanto, para acompanhar esta evolução, sem perder a qualificação dos dados espaciais, é necessária a adoção de padrões. Além disto, a complexidade das informações geográficas, em diversos aspectos, demanda técnicas de amostragem para mensurar e aferir a qualidade do conjunto de dados espaciais, a fim de garantir com embasamento estatístico, uma quantidade significativa e uma adequada distribuição espacial de suas amostras. Na área de Geociências é intuitivo pensar na correlação espacial de um fenômeno em estudo e a Geoestatística dispõe de ferramentas para identificar e representar o comportamento desta dependência. A análise espacial dos resultados de uma inspeção de qualidade de um produto cartográfico raramente é abordada na literatura, restrita apenas à conclusões descritivas e tabulares, baseadas no pressuposto da Estatística Clássica de independência dos dados observados. No presente momento está em implantação a Infraestrutura Nacional de Dados Espaciais do Brasil (INDE), onde diversos produtos cartográficos são disponibilizados à sociedade, junto com seus metadados geográficos. Os metadados facilitam o acesso ao dado espacial, mas atendem em parte aspectos relativos à qualidade do conjunto de dados. Desta forma, a presente dissertação propõe uma metodologia de inspeção da qualidade de conjuntos de dados espaciais da INDE, baseada em normas internacionais, conceitos de generalização e elementos de qualidade definidos na literatura, bem como a análise espacial dos resultados desta inspeção, usando métodos geoestatísticos e a representação desta aferição por meio de mapas de qualidade. O método de avaliação da qualidade de dados foi desenvolvido e aplicado sobre a Base Cartográfica Contínua do Brasil na escala 1:250.000 - BC250, com foco em determinados aspectos de qualidade. Os mapas de qualidade gerados mostraram regionalizações dos indicadores de qualidade inspecionados, confirmadas pela equipe produtora da referida base cartográfica, subsidiando usuários e os próprios produtores no entendimento do comportamento espacial da qualidade do produto cartográfico em estudo.

Os delineamentos sistemáticos são usados nas mais diversas áreas, como: florestal, horticultura, solos, etc. Na área florestal, os delineamentos sistemáticos são freqüentemente usados para estudos preliminares e têm o objetivo de testar o maior número de espaçamentos possíveis. No entanto, existem algumas limitações para a sua utilização. A primeira é o arranjo sistemático (não casualizado) das plantas, que não permite o uso das análises convencionais. A segunda é a alta sensibilidade para valores perdidos. Quando uma planta é perdida, o espaçamento das plantas vizinhas é alterado, assim esses valores não podem ser incluídos no conjunto de dados e informações consideráveis são excluídas das análises. O objetivo deste trabalho foi aplicar a metodologia geoestatística para identificação de dependência espacial em um experimento em delineamento sistemático tipo "leque", levando-se em consideração: a eliminação dos dados das plantas vizinhas aos valores perdidos e as informações de ocorrência de parcelas perdidas e o tempo que ocorreram. Os dados de volume sólido por planta utilizados neste trabalho são provenientes de um experimento de espaçamento de Eucalyptus dunnii em delineamento sistemático tipo "leque". Neste trabalho foram utilizados os dados referentes ao sexto ano, idade comercial de corte da espécie, com os seguintes procedimentos: eliminação dos dados das plantas vizinhas às plantas mortas (Modelo I); as informações de mortes das plantas foram consideradas como uma covariável no modelo (Modelo II) e além da covariável morte das plantas, também foi levado em consideração o tempo da ocorrência da morte (Modelo III). Os parâmetros do semivariograma foram estimados pelo método de máxima verossimilhança e para seleção de modelos, utilizou-se o Critério de Akaike (AIC). Os resultados obtidos permitem concluir que se identificou uma fraca dependência espacial, o que não justificaria considerá-la com a aplicação de um modelo geoestatístico. A função de correlação que apresentou melhor desempenho foi a Matérn com k = 2 para os três modelos considerados. Comparando-se esses modelos e seguindo o critério de Akaike, o modelo mais adequado foi o II, pois apresentou menor valor de AIC. / Systematic designs are utilized in many areas, such as: forestry, horticulture, soils, etc. In forestry, the systematic designs are frequently used for preliminary studies and they aim at evaluating the largest number of possible spacings. However, there are some limitations on their use. The first limitation is the systematic design (non-randomized) of plants, which does not allow the use of conventional analyses. The second is the high sensitivity to lost values. When a plant is lost, the neighboring plant spacings are altered, so these values cannot be added to the data collection, and a great sum of information is excluded from the analyses. This study aimed at applying geostatistical methods to identify the spatial dependence in the data analysis of a fan systematic design experiment, taking into account: the exclusion of neighboring plant data to the lost values and the information regarding the occurrence of lost parcels as well as the time of their occurrence. The plant solid volume data utilized in this study were taken from a fan systematic design Eucalyptus dunnii spacing study. The data utilized were referent to the sixth year, commercial age for cutting of the specie, with the following procedures exclusion of the data from a neighboring plant next to a dead tree (Model I); the information of tree mortality as covariable in the model (Model II); and the time of occurrence of tree mortality, besides the tree mortality covariable (Model III). The semivariogram parameters were estimated by the maximum likelihood method, and the model selection was done by the utilization of the Akaike's Information Criterion (AIC). It was possible to conclude from the result analyses that there is a weak spatial dependence, which does not justify neither taking it into account nor the utilization of a geostatistical model. The correlation function that showed the best performance was the Matérn, with kappa=2 for the three models considered. By the comparison of these three models and the utilization of the Akaike's Information Criterion, the most suitable model was Model II, as it showed lower AIC value.

Dans le cadre de recherches menées par l'ANDRA, qui visent à évaluer la faisabilité de créer un stockage de déchets radioactifs dans la formation argileuse du Callovo Oxfordien, cette thèse s'intéresse à deux étapes indispensables pour obtenir une image 3D du sous sol. La première étape concerne la cartographie de la géométrie de la formation. Celle-ci est déterminée à partir de temps pointés le long de profils sismiques, orientés suivant deux directions principales. Aux intersections, les valeurs enregistrées par deux profils sont différentes. Le faible nombre d'intersections ne permettant pas une étude détaillée du comportement spatial de ces différences, elles sont analysées par le biais du pseudo variogramme croisé. L'analyse variographique permet de choisir un modèle cohérent pour l'ensemble des profils. À partir de ce modèle une estimation du temps corrigée est présentée. La deuxième étape concerne l'étude de l'impédance, variable liée aux propriétés intrinsèques de la roche. Deux types de mesure sont disponibles. D'une part l'impédance sismique résultant de l'inversion géophysique de l'amplitude enregistrée le long de profils de sismique réflexion est largement étendue dans la zone d'intérêt. D'autre part, l'impédance log, résultant du produit de la densité de la roche et de la vitesse des ondes P, n'est connue uniquement dans quelques puits. Le comportement spatial bivariable, le long de la direction verticale, a permis de formuler l'hypothèse suivante : chaque mesure d'impédance est décomposée en une somme d'une variable Z (commune aux deux mesures) et d'un résidu différent pour chaque mesure. Sous certaines hypothèses supplémentaires, il est possible d'estimer la composante commune sur l'ensemble des sections sismiques. En complément à ces études, d'autres points ont été évoqués, par exemple la correspondance entre procédés géophysiques et géostatistiques, ou la prise en compte d'incertitude sur les amplitudes. / In the framework of researches carried out by ANDRA (the French agency for nuclear waste), which aim at evaluating the feasibility of creating a repository of radioactive waste in the Callovo Oxfordian clay formation. This thesis studies two key steps to obtain a 3D image of the formation: its geometry and its internal heterogeneity. The geometry of the sedimentary formation is determined from seismic time picking along profiles. These profiles are oriented along two main directions. At the intersections, the values registered by two profiles are different. The low number of intersections does not allow a precise study of the spatial behavior of these differences; they are analyzed via the pseudo-cross-variogram. The variography analysis allows the choice of a coherent model for all the profiles, from which an estimation of the corrected time is presented. The internal heterogeneity is performed through the study of the impedance, a variable linked to the intrinsic properties of the rock. Two types of measurements are available. On one hand, the seismic impedance resulting from the geophysical inversion of the amplitude recorded along seismic reflection profiles is densely distributed in the area of interest. On the other hand, the impedance log, resulting from the product of rock density and P wave velocity, is known at only few wells. Bivariate spatial behavior along the vertical direction has allowed the formulation of the following hypothesis: each impedance measurement can be decomposed into a sum of a variable Z (common to both measures) and a residual specific to each measure. Under certain supplementary hypotheses, it is possible to estimate the common component along the seismic sections. Some complements to these studies are mentioned, for example the correspondence between geophysical and geostatistical methods or the consideration of uncertainty in the amplitudes.

Canadian remote areas are characterized by a minimal human footprint, restricted accessibility, ubiquitous lichen/snow cover (e.g. Arctic) or continuous forest with water bodies (e.g. Sub-Arctic). Effective mapping of earth surface cover and land cover changes using free medium-resolution Landsat images in remote environments is a challenge due to the presence of spectrally mixed pixels, restricted field sampling and ground truthing, and the often relatively homogenous cover in some areas. This thesis investigates how remote sensing methods can be applied to improve the capability of Landsat images for mapping earth surface features and land cover changes in Canadian remote areas. The investigation is conducted from the following four perspectives: 1) determining the continuity of Landsat-8 images for mapping surficial materials, 2) selecting classification algorithms that best address challenges involving mixed pixels, 3) applying advanced image fusion algorithms to improve Landsat spatial resolution while maintaining spectral fidelity and reducing the effects of mixed pixels on image classification and change detection, and, 4) examining different change detection techniques, including post-classification comparisons and threshold-based methods employing PCA(Principal Components Analysis)-fused multi-temporal Landsat images to detect changes in Canadian remote areas. Three typical landscapes in Canadian remote areas are chosen in this research. The first is located in the Canadian Arctic and is characterized by ubiquitous lichen and snow cover. The second is located in the Canadian sub-Arctic and is characterized by well-defined land features such as highlands, ponds, and wetlands. The last is located in a forested highlands region with minimal built-environment features. The thesis research demonstrates that the newly available Landsat-8 images can be a major data source for mapping Canadian geological information in Arctic areas when Landsat-7 is decommissioned. In addition, advanced classification techniques such as a Support-Vector-Machine (SVM) can generate satisfactory classification results in the context of mixed training data and minimal field sampling and truthing. This thesis research provides a systematic investigation on how geostatistical image fusion can be used to improve the performance of Landsat images in identifying surface features. Finally, SVM-based post-classified multi-temporal, and threshold-based PCA-fused bi-temporal Landsat images are shown to be effective in detecting different aspects of vegetation change in a remote forested region in Ontario. This research provides a comprehensive methodology to employ free Landsat images for image classification and change detection in Canadian remote regions.

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Over a third of the world’s population lives at risk of potentially severe Plasmodium vivax malaria. Unique aspects of this parasite’s biology and interactions with its human host make it harder to control and eliminate than the better studied Plasmodium falciparum parasite. Spatial mapping of two human genetic polymorphisms were developed to support evidence-based targeting of control interventions and therapies. First, to enumerate and map the population at risk of P. vivax infection (PvPAR), the prevalence of this parasite’s human blood cell receptor – the Duffy antigen – was mapped globally. Duffy negative individuals are resistant to infection, and this map provided the means to objectively model the low endemicity of P. vivax across Africa. The Duffy maps helped resolve that only 3% of the global PvPAR was from Africa. The second major research focus was to map the spatial distribution of glucose-6-phosphate dehydrogenase enzyme deficiency (G6PDd), the genetic condition which predisposes individuals to potentially life-threatening haemolysis from primaquine therapy. Despite this drug’s vital role in being the only treatment of relapsing P. vivax parasites, risks of G6PDd-associated haemolysis result in significant under-use of primaquine. G6PDd was found to be widespread, with an estimated frequency of 8.0% (50% CI: 7.4-8.8%) across malarious regions. Third, it was important to represent more detailed descriptions of the genetic diversity underpinning this enzyme disorder, which ranges in phenotype from expressing mild to life-threatening primaquine-induced haemolysis. These variants’ spatial distributions were mapped globally and showed strikingly conspicuous distributions, with widespread A- dominance across Africa, predominance of the Mediterranean variant from the Middle East across to India, and east of India diversifying into a different and diverse array of variants, showing heterogeneity both at regional and community levels. Fourth, the G6PDd prevalence and severity maps were synthesised into a framework assessing the spatial variability of overall risk from G6PDd to primaquine therapy. This found that risks from G6PDd were too widespread and potentially severe to sanction primaquine treatment without prior G6PDd screening, particularly across Asia where the majority of the population are Duffy positive and G6PDd was common and severe. Finally, the conclusions from these studies were discussed and recommendations made for essential further research needed to support current efforts into P. vivax control.

Ces travaux présentent des avancées théoriques pour l'application de l'approche EDPS (Équation aux Dérivées Partielles Stochastique) en Géostatistique. On considère dans cette approche récente que les données régionalisées proviennent de la réalisation d'un Champ Aléatoire satisfaisant une EDPS. Dans le cadre théorique des Champs Aléatoires Généralisés, l'influence d'une EDPS linéaire sur la structure de covariance de ses éventuelles solutions a été étudiée avec une grande généralité. Un critère d'existence et d'unicité des solutions stationnaires pour une classe assez large d'EDPSs linéaires a été obtenu, ainsi que des expressions pour les mesures spectrales associées. Ces résultats permettent de développer des modèles spatio-temporels présentant des propriétés non-triviales grâce à l'analyse d'équations d'évolution présentant un ordre de dérivation temporel fractionnaire. Des paramétrisations adaptées de ces modèles permettent de contrôler leur séparabilité et leur symétrie ainsi que leur régularité spatiale et temporelle séparément. Des résultats concernant des solutions stationnaires pour des EDPSs issues de la physique telles que l'équation de la Chaleur et l'équation d'Onde sont présentés. Puis, une méthode de simulation non-conditionnelle adaptée à ces modèles est étudiée. Cette méthode est basée sur le calcul d'une approximation de la Transformée de Fourier du champ, et elle peut être implémentée de façon efficace grâce à la Transformée de Fourier Rapide. La convergence de cette méthode a été montrée théoriquement dans un sens faible et dans un sens fort. Cette méthode est appliquée à la résolution numérique des EDPSs présentées dans ces travaux. Des illustrations de modèles présentant des propriétés non-triviales et reliés à des équations de la physique sont alors présentées. / This dissertation presents theoretical advances in the application of the Stochastic Partial Differential Equation (SPDE) approach in Geostatistics. This recently developed approach consists in interpreting a regionalised data-set as a realisation of a Random Field satisfying a SPDE. Within the theoretical framework of Generalized Random Fields, the influence of a linear SPDE over the covariance structure of its potential solutions can be studied with a great generality. A criterion of existence and uniqueness of stationary solutions for a wide-class of linear SPDEs has been obtained, together with an expression for the related spectral measures. These results allow to develop spatio-temporal covariance models presenting non-trivial properties through the analysis of evolution equations presenting a fractional temporal derivative order. Suitable parametrizations of such models allow to control their separability, symmetry and separated space-time regularities. Results concerning stationary solutions for physically inspired SPDEs such as the Heat equation and the Wave equation are also presented. A method of non-conditional simulation adapted to these models is then studied. This method is based on the computation of an approximation of the Fourier Transform of the field, and it can be implemented efficiently thanks to the Fast Fourier Transform algorithm. The convergence of this method has been theoretically proven in suitable weak and strong senses. This method is applied to numerically solve the SPDEs studied in this work. Illustrations of models presenting non-trivial properties and related to physically driven equations are then given.