Preliminary geomorphologic characterization of Rio das Pedras basin, Guarapuava – PR

Abstract

The basin of Rio das Pedras, incised in the basalts of Serra Geral Formation, is analyzed by means of the basic morphometric characteristics of its main subbasins, considered as sample units. The variation of the drainage density is correlated to the relief conditions which result from the drainage arrangement and its correlation with the geologic structure and lithology. The utilization of drainage density, altimetric amplitude, relief relation, roughness and link frequency indices, allowed to identify, by means of the differences in the values, distinct geomorphologic sectors in the Rio das Pedras basin. The sector II is represented by a deepey incised plateau, while the remaining less incised top characterizes the (sub) sector IIb. The sector I borders the plateau and hold indices with small values. The combined analysis of rugosity with its components (drainage density and altimetric amplitude) made it possible to assess, in relative terms, atributes of slopes (lenght and gradient), as well as its implications in the hidrologic functionality and sediment removal in the subbasins. Keywords: Morphometry; drainage networks; slopes.