GEOGRAPHIC INFORMATION SYSTEM (GIS) APPLIED TO THE CALCULATION OF MORPHOMETRIC INDEX IN WATERSHED

Abstract

doi: 10.12957/geouerj.2016.18520

The geomorphology constitutes a scientific branch who aims to study the relief forms, with special focus in the analysis of its genesis and evolution. About that, basing in the main theories over the existence of variety of relief forms (as Penck and Davis theories), Guerra and Guerra (2011) state that the simultaneous or alternating action of the internal and external forces over the surface are responsible for its irregularities. Thereafter, this set of forms presented by relief since its genesis until present day describe its development or evolution cycle. Based on the above and with special attention on the geomorphological studies of drainage basins, Horton (1945) attests his worrying about the lack of tools for adequate investigation of the level of relief development, judging that the researches so far were based fundamentally in qualitative aspects. So, in order to fix such questions, the mentioned author advises the use of quantitative tools for more incise studies over the level of relief development. In that way, the present paper aims to analyze the relief of Vieira river drainage basin through morphometric indices presented by Christofoletti (1980), having as fundamental base the studies of Horton (1945) and Strahler (1952 and 1957). In order to obtain the morphometric variables, in Geographic Information System (GIS) environment, the altimetry data of Digital Elevation Model (DEM) from SRTM mission were used as base. At end, the indexes indicated mainly that the Basin of Vieira River has relief predominantly between flat and wavy, with a drainage system weakly drained and erosive activity in stability stage.