Modelagem de fenômenos intempéricos e erosionais em vertentes : uma aproximação de suas componentes não-lineares com base em métodos de mineração de dados / Modeling of soil weathering on hillslopes : coping with nonlinearity and coupled processes using a data-driven approach
AUTOR(ES)
Fábio Iwashita
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
06/05/2011
RESUMO
This Doctoral thesis aims to explore the relationship between soil physical-chemical properties and relief morphometry, and quantifying these relationships to build conceptual and predictive models. Self-organizing maps and Geographic Information Systems modeling are here used to investigate nonlinear correlations associated with chemical and physical denudation; which are factors connected with hydrological phenomena and soil evolution. Three study cases are presented: soil chemical weathering within the limits of the Parana State, southern Brazil (22 variables and 304 samples), physical transport of sediments in the alkaline intrusive complex of Poços de Caldas, southeastern Brazil (9 variables and 29 samples), and hydrochemistry of Serra Geral aquifers also in the Parana State (27 variables and 976 samples). The method combining stochastic simulation and data mining allows exploring the relationships between topography, soil texture and soil geochemistry. In the Parana State, higher regions and areas with convex morphometry shows, respectively, higher and lower denudation rates of mobile (e.g., Ca) and less mobile (e.g., Al) elements. The same pattern is observed for soil particle size. In this case, high proportion of sand is found in highlands and convex areas inside the basin, and high clay content, with low hydraulic conductivity, occurs in convex regions, near drainage channels. The spatial behavior of the Serra Geral aquifer?s hydrochemistry pointed out to areas with potential connectivity with the Guarani aquifer system, recent recharge areas, and long-standing waters. Predictive, unbiased models are built for soil properties on the premise that weathering and morphology are related through a two-way dependent process, where the physical and chemical denudation delineates the elevations of the land surface, and terrain morphometry is a factor that characterizes the physical-chemical conditions of the soil
ASSUNTO(S)
geoestatistica geostatistics self-organizing maps mapas auto-organizaveis data mining mineração de dados
