Taxonomia do Relevo do Baixo Curso da Bacia Hidrográfica do Santo Antônio, Ilha do Maranhão

Abstract

The lower course of the Santo Antônio watershed, located in the northeastern portion of Maranhão Island, is the area of study in this work. With a total area of 43.12 Km², the low course extends its drainage in portions of the municipalities of São José de Ribamar and Paço do Lumiar. The general objective of this research was to analyze the geomorphology of the lower course of the Santo Antônio River through the taxonomy of the relief. The specifics were: describe the geoenvironmental aspects of the study area; characterize the relief compartments of the selected area and identify the taxonomic levels of the relief of the lower course of Santo Antônio, Maranhão Island. Topics were discussed on the importance of cartography for geomorphology and on morphography, morphometry and taxonomy as tools for the study of the relief. To achieve what was objectified in the project, some steps were followed such as: bibliographic and cartographic survey, organization of the work environment, field work; spatialization of the taxonomy of the relief; compilation and treatments of the data obtained. From this, geological, geomorphological and water data of the study area were obtained as research results. It should be noted here that the geoforms were analyzed from the taxonomic proposal presented by Ross (1992), which are mainly included in the 3rd, 4th, 5th and 6th taxa. In the drainage analyzed through the fluvial hierarchy proposed by Strahler (1952), it is concluded that in the lower course of the analyzed basin there are channels that vary from first to third order. In addition, the lower course of the Santo Antônio River is characterized as a dendritic pattern and exorheic drainage, flowing into the Atlantic Ocean