The heterogeneity and landscape changes in the Iguaçu-Sarapuí drainage basin (RJ) and its impacts on urban floods 

The aim of this study was to identify and analyze the heterogeneity and landscape changes based on the relationship between land cover and land use patterns and the permeability caused by these changes that influence the occurrence of urban floods in the Iguaçu-Sarapuí drainage basin (RJ), from remote sensing data processed through an Open Source Geographic Information System software.Initially, we looked for identifying and quantifying the Coverage and Land Use patterns in order to correlate them with the surface permeability. Later, this database was useful for relating the defined areas by the Company of Research of Mineral Resources (Companhia de Pesquisa de Recursos Minerais – CPRM) as susceptible to the occurrence of floods. The results indicated an increase in the class defined as built-up areas and reduction on dense vegetation and pasture classes and on free field areas. Consequently, the impermeable areas also increased while permeable areas were reduced.This aspect deserves extreme attention whereas the impermeable areas were included as susceptible to flood occurrences, making this process to influence the hydrogeomorphological dynamics on different scales. Besides that, the importance of vegetation in the reduction of impermeable covers in the areas of Units of Conservation was verified. This way, understanding the drainage basin as a basic unit of geomorphological evolution and an excellent management unit for both natural and social elements, due to its integrative aspect, it was tried to emphasize the interactions and interferences in the fluvial system in this area and to present the possibilities for the usage of geotechnologies available for free and through an easy access that can be used as essential instruments for the study of the heterogeneity and changes of the landscape throughout the time.