Arroios Jaguarí–Mirim, Inhadiju e Piquiri em seu Contexto Geomorfológico

Abstract

The present article aims at the mapping of the GeomorphologicUnits of the Hydrographic Basins of the Jaguari Mirim, Inhadiju, and PiquiriStreams, located in the west of Rio Grande do Sul – Brazil. To make thiscartographic document, was necessary some catchments of morphometricalproperties of relief, geological, soils and erosion process. Data analyzesdefined six units characterized as: Unit I – Plane Top Relief in VolcanicSpill: shows plane relief with relatively low erosive processes andintemperism; Unit II – Hills in Volcanic Spill: slightly wavy areas underneaththe plateau summit; Unit III – Hills and Small Size Hills in Volcanic Rock:formed by strongly wavy relief and with scarps; Unit IV – Small Size Hillsin Sandstone: composed by isolated small size hills with origin associatedto the existence of united sandstones that keeps the plane top relief; UnitV – Hills in Sandstone: Relief of hills located at the medium and low courseof the streams, with the occurrence of accelerated erosive processes whichproduce sand dunes and accelerated erosions, and sometimes with theblooming of united sandstones in the half-slope or in the top; Unit IV -Plane Relief in Low Altitude: Relief of plane topography that predisposesthe superficial dynamic processes, generating the accumulation of sedimentsas well as the formation of fluvial terraces. The fragility of the naturalsystems, in face of the antropic interventions, is largely associated to itsgenetic characteristics. Thus, the geomorphologic analysis in theenvironmental studies is a tool for the maintainable planning of the activitiesintroduced in the region.