Morphometry of the river basin São João, MG: a proposal for understanding the limits and the dynamics of erosive surfaces

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOThe morphometric parameters of relief surface are essential for characterizing and understanding the landscape formation, especially in areas that have been undergone erosion and tectonic processes, as the case of the Sao Joao River Basin in southwest of Minas Gerais state. In order to recognize tectonic features that could interpose the development of the channel and ultimately affect the erosion cycles, were performed a series of geomorphological analysis, such as: isobase, factor transverse topographic symmetry and asymmetry of the drainage basin, and the curve and hypsometric integral. These results were produced through rates obtained by the TecDEM, software used to compile the entire procedure and routine, just using spatial information of the digital elevation model (SRTM). These analyzes satisfactorily gave the understanding of the structures and relief in the basin context, and thus, showing the topography and boundary areas, the erosive dynamic displacement of channels belonging to fourth and fifth basins orders, and finally the moment of transition relief.Os parâmetros morfométricos da superfície do relevo são essenciais para a caracterização e o entendimento da formação de uma paisagem, especialmente em áreas que passaram por processos erosivos e tectônicos bem marcados, como o caso da região da Bacia do Rio São João, no sudoeste de Minas Gerais. Com o propósito de reconhecer os traços tectônicos que pudessem interferir no desenvolvimento do canal e por fim afetar os ciclos erosivos, foram realizadas uma série de análises geomorfológicas; tais como a Isobase, o Fator de simetria topográfica transversal com assimetria da bacia de drenagem e a Curva e integral hipsométrica. Estes índeces foram produzidos através do software TecDEM, que compilou em sua interfacie de trabalho todo o procedimento e rotina, utilizando-se apenas das informações espaciais do modelo digital de elevação (SRTM). Estas análises, favoreceram satisfatoriamente o entendimento das estruturas e do relevo no contexto da bacia, assim evidenciando os domínios topográficos e limites das superfícies, a dinâmica erosiva, o deslocamento dos canais pertencentes as bacias de quarta e quinta ordem, e por fim o momento de transição do relevo172241252FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2009/04418-42009/10547-12010/17423-3, 2011/233257; 308629/2015-9The morphometric parameters of relief surface are essential for characterizing and understanding the landscape formation, especially in areas that have been undergone erosion and tectonic processes, as the case of the Sao Joao River Basin in southwest of Minas Gerais state. In order to recognize tectonic features that could interpose the development of the channel and ultimately affect the erosion cycles, were performed a series of geomorphological analysis, such as: isobase, factor transverse topographic symmetry and asymmetry of the drainage basin, and the curve and hypsometric integral. These results were produced through rates obtained by the TecDEM, software used to compile the entire procedure and routine, just using spatial information of the digital elevation model (SRTM). These analyzes satisfactorily gave the understanding of the structures and relief in the basin context, and thus, showing the topography and boundary areas, the erosive dynamic displacement of channels belonging to fourth and fifth basins orders, and finally the moment of transition relie