Fatores de controle dos fluxos fluviais de material em suspensão em diferentes cenários climáticos na bacia do rio Solimões

Abstract

This thesis analyzes the main factors that control erosion vulnerability and suspended sediment yields in sixteen reference stations of the Solimões River. Geotechnological methods and numerical analyses were used to model the interaction of these factors based on observational and physiographic data. Data from different sources and in multiple formats were integrated to characterize the natural and anthropogenic factors affecting these areas. Vulnerability indices were defined based on the relative empirical values of the relationship between morphogenesis and pedogenesis for each of the following variables: geology, geomorphology, pedology, vegetation, land use and climate, ranging from 1,0 (morphogenesis process predominance) to 3,0 (pedogenesis process predominance) and 2,0 (for intermediary class). The integration of these vulnerability indices was performed using map algebra. Hydrosedimentological scenarios were generated based on a spatial analysis of the factors controlling the liquid discharge (Q), solid discharge (Qs), solid flow budget and specific production of sediment at sixteen locations. For both the suspended sediment and liquid discharge scenarios, we calculated and analyzed data using an interannual approach with the adopted period as an independent variable. The hydrological regime series from the 1970s was obtained, and the calculation of Qs considered only periods with compatible Q measures and sediment samples. Using the results, we correlated the vulnerability of each contribution area to the suspended sediment yield and concluded that Solimões River basin has an average/high vulnerability morphodynamics.