Evaluation of water quality using the fuzzy theory

Abstract

Water quality is currently treated in all fields of engineering, with a view to developing a sustainable environment. In this scenario, the assessment of water quality is essential and in this work, which was
evaluated by monitoring of indicators of the trophic level of water reservoirs Jacarecica I in the state of Sergipe. In this, we carried out physicochemical analyzes and constituted a fuzzy language for classification of environmental data. Fuzzy logic is an artificial intelligence technique that is based on expert knowledge of the phenomenon to be treated, to have a heuristic language translated numerically. For use of fuzzy theory, we calculated the trophic index of the reservoir through the correlation of modified Carlson and established the boundaries for the fuzzy variables. The chemical variables were used to clorifila-a, total nitrogen and phosphorus and have been translated into four levels of eutrophication of water body (oligotrophic, mesotrophic, eutrophic and hypereutrophic). Thus, the results showed that the level of water quality in reservoir Jacarecica I are between oligotrophic and eutrophic and the use of fuzzy logic was applied satisfactorily to show these levels of eutrophication.