Identificação e mapeamento de áreas suscetíveis a movimentos de massa e inundações/alagamentos na área urbana de Maceió, Alagoas

Abstract

The process of urban expansion occurring in various cities in Brazil must be approached with caution by the Public Authorities, as the lack of urban planning policies, non-compliance with municipal planning (Master Plan), and deficiencies in monitoring interventions in cities can lead to incorrect use of spaces and disorderly occupation of environmentally restricted areas, resulting in processes involving the growth of areas sensitive to population occupation. Human settlements on slopes and near bodies of water bring about significant changes in natural dynamics, exposing individuals to hydrological events and mass movements. Regarding landscape analysis, geographic information systems offer a range of techniques and tools for interpreting and manipulating spatial data, facilitating the generation of information that supports evaluation and decision-making. Thus, this study identified, through geoprocessing and supported by procedures involving Multicriteria Decision Analysis (MCDA), specifically using the Analytic Hierarchy Process (AHP), the ability to compare and assess different options based on weighted criteria and subcriteria, assigning weights and scores indicating the priority of each variable in relation to each of its characteristics. This was done to identify areas with susceptibility to mass movements and floods/flooding, aiming to support environmental preservation efforts and enhance comprehensive knowledge of the urban area of Maceió. This is intended to establish a future population management and planning plan that prioritizes land use strategies with the definition of suitable areas for occupation. Finally, the data indicate that the Urban Zone of Maceió is more susceptible to floods/flooding than mass movements. Therefore, municipal public policies need to pay closer attention and undertake more actions addressing this issue, such as infrastructure and urban drainage works, while also addressing situations that leave the population more vulnerable to mass movements. This is a point of significant interest in urban planning, which should also be taken into account in the revision of the main instrument for urban management and planning, the Municipal Master Plan, which, at the time of this work, is eight years behind in its revision.