Contribuição da geomorfologia para estudos de expansão urbana

This article discusses some theoretical and methodological assumptions about the transformations of the original morphology from urban sprawl, considering the changes and consequences in the forms and dynamics of relief in the city of Santa Maria - RS. Contemporary, the geomorphological approach of the urban sites has been gradually explored and applied, conducting studies related to changes in surface coverage of the urban terrain, generated by the phenomenon of urbanization and exponential growth of urban populations. In this light, the anthropic intervention, appropriating or expropriating the natural environment, over all in providing any form of urban settlements, modifies the original morphology of the relief in order to take the needs of setting engineering architectures (houses, buildings, streets, highways, railways, etc.). Therefore, the sum of human intervention as a result produces morphology of the relief no longer original, but anthropogenic, context in which the structuring of the urban centers transforms the environment, leaving marks on the landscape, changing its original morphology in a historical accumulation of time (space-time understanding). This fact characterizes the geologic period called Quinary or Tecnogenic, which refers to the new soil coverages and new "geological facies" in formation process, strongly influenced by human activity (Oliveira 1995). Thus, the man acting as a social being allied with the technique produces changes other than those of natural origin, indicating the human capacity to create artificial morphologies in short periods of time, participating qualitatively in the geomorphological processes, evidencing registers of its action on the landscape under the Tecnogenic Deposits form. According to Moura (2011: 180), the anthropic registers should be included within the natural systems and should be analyzed from the apprehension of what solidifies in the landscape, in fact, the vegetal covering, the agricultural uses, the buildings, dams, landfills, and must also "consider that the concrete expressions in the landscape are dynamized by procedural forces that are inserted into the socioeconomic causality." Therefore, the Geomorphological and Anthropogeomorphological (Anthropogenic Geomorphology) approaches are noticeably important for taking an explicative comprehensive character between the natural environment studies and human/social environment studies, identifying the potentialities for use and suitable occupation to the development of human activities, effect of integrative role between the elements.