Mapeamento de áreas suscetíveis a deslizamentos no município de Pato Branco, Paraná com a aplicação do modelo SHALSTAB

Este trabalho compara modelos matemáticos de estabilidade de encostas associados a técnicas de mapeamento temático em SIG. O objetivo principal foi avaliar a aplicação do modelo SHALSTAB no mapeamento de áreas suscetíveis à ocorrência de escorregamentos na região de Pato Branco, Paraná, buscando determinar a quantidade de chuva necessária para desencadear estes eventos extremos e comparar com resultados de trabalhos anteriores que determinaram os fatores de segurança das encostas dessa área. Os resultados obtidos demonstraram que ambas metodologias analisadas mostraram-se aptas como ferramenta para identificar zonas de susceptibilidade à ocorrência de escorregamento raso, uma vez que os deslizamentos ocorridos na cidade estão localizados em áreas consideradas instáveis pelos dois métodos.This paper compares mathematical models of slope stability associated with thematic mapping techniques in GIS. The main objective was to evaluate the application of SHALSTAB model in the susceptible mapping areas to the occurrence of landslides in Pato Branco, Paraná State, aiming to determine the needed amount of rain to trigger these extreme events and to compare, with previous studies results, what have determined the security factors of the slopes in this area. The results showed that both analyzed methodologies proved suitable as a tool for identifying susceptibility to the occurrence of slip shallow areas, once the slips occurred in the city are located in areas considered unstable by both methods

Future Land-use and Land-cover Scenarios for Mapping Flood-prone Areas in Pato Branco City, Brazil

Urban flooding is the most common type of disaster and the one that hit people most. Unplanned urbanization processes increase the recurrence of these events due to soil impermeabilization. Thus, land-use and land-cover is an important factor for urban flood research. Besides, mapping flood-prone areas has been an alternative for disaster prevention and urban planning. However, the use of future land-use and land-cover scenarios for flood mapping is a factor that still requires investigation. The study that is being developed by the authors of this paper aims to identify flood-prone areas in the upper third of the Ligeiro River basin in the city of Pato Branco, Parana, Brazil. For this purpose, this research makes use of the GIS-AHP integration, considering a current scenario and future land-use and land-cover scenarios. Therefore, the objective of the present study is to construct possible land-use and land-cover scenarios, according to municipal legislation, that could serve as a basis for mapping flood-prone areas. Two scenarios were built using Geographic Information Systems software. This tool proved to be efficient in the elaboration of maps and land representation. Pato Branco already has a history of flooding with the current scenario of land-use and land-cover. With future land-use and land-cover scenarios, it is possible to verify the influence of urban sprawl on urban flooding. Keywords: Land-use and land-cover (LULC), Floods, Geographic Information Systems (GIS), Analytic Hierarchy Process (AHP