Tempo de concentração em três bacias hidrográficas de Uberlândia, Minas Gerais

Abstract

The presente study aims to quantify the concentration time in three watersheds in Minas Gerais, comparing it with data empirical resulting using equations in studies involving hydrology. To attainment of results it was necessary the characterization of use and occupation of the ground in the basin, using multispectral images with a minimum resolution of 30 m. At the same time, were obtained truths of fields through GPS devices. Moreover, through these devices were obtained quoted points and the hydrography that, together with the digital elevation model, made enabled us to trace the water mesh of the studied watersheds. To attainment of these information, the QGIS 2.18 software was used. The studies occurred place in the Gloria, Água Vermelha and Fundo River Basins, sub-basins of the Araguari Watershed. The river basins already counted on instruments to assess the water level of the respective streams and also rain gauges. As a result of this research, it was found that the empirical Simas-Hawkins equation presented the best performance to estimate of the concentration time, for the Watershed of the Gloria Stream, in relation to the data obtained with the use of the hydrographs. For the Watershed of the Água Vermelha stream, the empirical Izzard equation presented the best result, even with a relative error of 37%, when compared to the values obtained by the hydrograms. In the Watershed of the Fundo stream the Kirpich empirical equation presented the most satisfactory result.