Aplicação de análise multicritério para mapeamento de áreas suscetíveis à poluição hídrica: estudo de caso do município de Erechim, RS

Abstract

Among the natural resources that suffer most from the great influence of human action, water resources stand out. For the management of such problems, an excellent tool is the use of geotechnologies. Therefore, the objective of this paper was to carry out a multicriteria analysis for the mapping of areas influential to water pollution in the municipality of Erechim (RS/Brasil). For that, we used the methodology of multicriteria analysis with weighted linear combination based on the variables of land use and occupation, proximity to the watercourse, altimetry and slope. The criteria were normalized with a scale from 0 to 100 to unify the measurement scales. To determine the relative importance of each criterion, he used the Analytical Hierarchical Process (AHP) method through consultation with a group of ten specialists. With this methodology, it was possible to obtain the specialization of areas with great potential for water pollution risk, in order to be classified into five classes: very low, low, medium, high and very high. The consolidation of data related to the experts' responses determined the importance of the criteria, namely: land use and occupation (49.11%), proximity to the watercourse (34.88%), altimetry (9.625) and slope (6.15 %). With regard to areas influencing water pollution, the study found that about 2.05 and 17.57% are classified as areas with a very high and high risk of influence, respectively. Thus, it is concluded from the results, that the use of multicriteria assessment methods associated with geoprocessing techniques, is suitable for mapping the areas influencing water pollution, enabling the use for the management of natural resources and supporting decision makers.