Análise da dinâmica energética de bacias de drenagem em área de rochas siliciclásticas, na Serra do Espinhaço Meridional, com a utilização do índice de Hack

Abstract

The Pardo and High Jequitinhonha drainage basin are two of the most important basins of the Meridional Espinhaço Mountain Range. They are responsible for water supply and the landforms evolution, creating different environments, even those situated on siliciclastic rocks. Aiming to understand the environment dynamics, the main objective of this work is to compare the energetic dynamics of both drainage basin exclusively located on siliciclastic rocks from Espinhaço Supergroup, Minas Gerais. For this, the Stream-Gradient Index and other parameters were used, assisted by field work. This dissertation was organized in two chapters, preceded by one introductory chapter and at the end being presented the final remarks. In the second chapter (paper 1) the objective was to analyze the consistency of the methodological procedures and results using the full segment of a river and comparing them with the results obtained by the use of methodological procedures to the size of the segments of hierarchical drainage, seeking to obtain a better understanding of the specificities of this index, as well as determining which method provides better results about the energy dynamics of the basins. The third chapter (paper 2) provides an analyses about the relation between energy and competence in both drainage basin, besides presenting results on the efficiency of using the Stream-Gradient index in humid tropical environments. Results indicate different evolution patterns between the two basin, within the same lithological domain. They also validate the index calculation through segments of hierarchical drainage, which allows realizing the energy variations in more detail scales. Further, legitimizes the value of the measurements obtained by the index, and then validated in field. The field work was important for the understanding of the data, mainly due to local peculiarities of each river, form, litoestructure and process involved in their energy dynamics.