Spatial modeling of vulnerability to flooding in the municipality of Marabá-PA via fuzzy logic

Abstract

The flood event is the one that most affects people around the world and has been increasing considerably in Brazil, mainly in urban areas. This phenomenon causes immediate damage to the environment, as well as directly affects the population, regardless of their social and economic status. According to the Brazilian Atlas of Natural Disasters, the state of Pará had 256 flood events in the period from 1991 to 2012. Therefore, the objective of this research is to map areas susceptible to flooding using nine input variables - altitude, curvature, slope, SPI, TWI, river distances, pedology, precipitation and land use and land cover - through Fuzzy Logic and geoprocessing techniques in periods of greater and lesser precipitation. The choice of the study area is due to the fact that Marabá is the municipality that presented the highest number of occurrences of floods in the state of Pará and also due to the lack of information and studies on the physical environment and issues related to flooding in the Amazon region. The results found showed that most of the vulnerability to flooding is located in the urban area of the territory under study, corresponding to 1011.69 km², in the period of greatest precipitation. Therefore, the flood vulnerability map can be used by public agencies as an environmental management tool and to aid in decision-making in order to minimize economic and social impacts.