Proposta metodológica para o zoneamento de áreas aptas à urbanização

Abstract

Planning and control of use, subdivisions and urban occupation are competencies of the municipal public authorities, since the absence of these actions can result in serious socio-environmental impacts in the urbanization process. Faced with this problem involving urbanization with socio-environmental issues, the present study consists of using geoprocessing tools and Geographic Information System (GIS) to identify areas suitable for urban expansion in the municipality of Lagoa Dourada (MG). With the work of QGIS software, an open source Geographic Information System (GIS), and spatial data freely available on public access platforms, the area of interest was delimited, comparison and correction of data from the drainage network, creation of water resource preservation areas and delimitation of highways and service lanes and non-buildable lanes of highways. The Analytic Hierarchy Process (AHP) method was used in this study, where the score and weights of the variables were defined to assign importance through a comparison scale between the criteria. In the study, 13 variables of environmental relevance and 5 for the constructive aspect of suitability for urbanization were used, being evaluated independently to obtain the weights in the AHP method. Thus, the consistency ratio values were 3.5% for the weights of variables of environmental relevance and 4.60% for the weights of variables of constructive interest, which confers acceptability of the weight values obtained (less than 10%), according to the AHP method. After defining the scores according to the typologies of each variable, as well as their respective weight, compared with the other variables in each category, an equation was proposed to delimit the areas suitable for urbanization. Thus, the area of interest for urbanization in the municipality of Lagoa Dourada has 3,288.05 hectares (ha), of which 75.19% presented high suitability for urbanization (2,472.19 ha), 15.16% with medium suitability (498, 59 ha), 4.46% of the area with very high suitability (146.64 ha), 3.41% had low suitability (112.17 ha), and finally, only 0.03% had very low suitability for urbanization (0.91 ha). The only areas that received a score of 0, unsuitable for urbanization, were the regions located in the right-of-way and non-buildable lanes of highways, representing 1.75% of the area of interest for urbanization (57.54 ha). Proof of the applicability of the methodology and its validation occurred by monitoring urbanization in the municipality through historical images from Google Earth and subdivisions under construction, whose locations occurred in the most suitable regions for this purpose.