Understanding flooding processes of large wetlands of the bolivian amazon through in situ observation, remote sensing and numerical modeling

• Ano de defesa: 2017
• Autor(a) principal: Alex Ovando Leyton
• Orientador(a): Javier Tomasella, Celso von Randow
• Banca de defesa: Jean-Michel Martinez, Conrado de Moraes Rudorff
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Instituto Nacional de Pesquisas Espaciais (INPE)
• Programa de Pós-Graduação: Programa de Pós-Graduação do INPE em Ciência do Sistema Terrestre
• País: BR
• Link de acesso: http://urlib.net/sid.inpe.br/mtc-m21b/2017/04.18.17.29

The Amazonian wetlands of Bolivia, known as the Llanos de Moxos, are believed to play a crucial role in regulating the upper Madeira hydrological cycle, the most important southern tributary of the Amazon River. In addition to its rich natural diversity, the Llanos were the setting for many complex pre-Columbian societies. Because the area is vast and sparsely populated, the hydrological functioning of the wetlands is poorly known. In this thesis we show the feasibility of using multi-temporal flood mapping, based on optical (MODIS M*D09A1) and satellite altimetry (ENVISAT RA-2 and SARAL Altika altimeters) to characterize and monitor flood dynamics and to optimize floodplain simulations within a hydrological model (MHD-INPE model). Initially we analyzed the hydrometeorological configurations that led to the major floods of 2007, 2008 and 2014 in the upper Madeira Basin; Then, with the inclusion of altimetric information, which provided a vertical component for the two-dimensional flood maps, we analyzed the flood dynamics for the whole 2001-2014 period, including both extension and water stage variations that allowed to have initial surface water storage estimations. Finally, we critically analyzed how numerical modeling of the wetlands can be improved using additional remote sensing techniques. Our results showed that large floods are the result of the superimposition of flood waves from major sub-basins of the region and the strong influence of the occurrence of intense rainfall over saturated areas. We had identified relevant features of the flood regime, identifying three groups with particular characteristics in function of its connectivity and dependence to the Andes and piedmonts or to local processes and classified the hydraulic function of the wetlands based on remote sensed imagery. Finally, we demonstrate that remote sensing information is of major importance for improving floodplain simulations using hydrological models. However, there are still clear limitations in the existent remote sensed products for achieving seamless predictions of the hydrological behavior of the Llanos under changing climate.