Biorremediação para a melhoria da qualidade da água em ambiente aquático lêntico urbano

Abstract

One of the main environmental issues currently discussed is the pollution of urban water resources, resulting from the lack of waste treatment and irregular land use. The degradation of water bodies, such as rivers and lakes, due to the discharge of domestic sewage increasingly compromises water quality and public health. The Solón de Lucena Park Lagoon, in João Pessoa, PB, is an example of an environment impacted by this pollution. Given this scenario, the present study aims to implement and evaluate a biotreatment system to improve the water quality of the Solón de Lucena Park Lagoon. To achieve this, a systematic literature review was conducted to identify studies addressing bioremediation techniques and their effectiveness. Water quality was analyzed before and after the implementation of the system using physical, chemical, and biological parameters. Samples were collected at three different points in the lagoon, with three replicates at each location. To compare environmental parameters between the pre- and post-biotreatment periods, statistical analyses were performed: the paired t-test for normally distributed data and the Wilcoxon test for non-normally distributed data, using R software. The results generally indicated a reduction in pollutant concentrations such as ammonia, orthophosphate, nitrate, and nitrite after the implementation of biotreatment. Additionally, an increase in species diversity was observed, especially rotifers, which are bioindicators of eutrophic environments. The Shannon Index revealed an increase in biological diversity at all sampling points. Despite the observed improvements, such as the reduction of most pollutants and an increase in zooplankton diversity, the trophic state index remained classified as hypereutrophic. This highlights the need for complementary actions, such as expanding bioremediation modules, introducing predatory fish to control tilapia populations, or allowing fishing activities to further reduce the lagoon's trophic state.