Avaliação do processo de eutrofização do rio Paraíba do Meio - Alagoas, durante o ano hidrológico de 2013

Abstract

Rivers are important water resources for the survival of humanity and all living beings on the planet, since they are fundamental, whether for the maintenance of life on planet Earth or for social and economic purposes. In this sense, it is indisputable that the rational use of water resources is necessary, as their inappropriate use causes changes in their quality, compromising them in their different forms of use. Thus, as a result of the irrational use of water resources, eutrophication stands out, considered an environmental problem that begins to spread. In this sense, the objective of this research was to evaluate the degree of eutrophication of the Paraíba do Meio river, which flows through the states of Pernambuco and Alagoas, in Brazil. The sector selected for research is contained in the state of Alagoas, having the hydrological year of 2013 as a reference. For this, the Carlson Trophic State Index (TSI) proposed in 1977 was used, relating it to its flow and precipitation. of the Paraíba do Meio river compared to other tropical rivers. It was also necessary to determine the concentration of nutrients Chlorophyll a and Phosphorus (P) based on data collected monthly in 2013 by the Hydrochemistry Laboratory, one of which is part of the Integrated Laboratories of Marine and Natural Sciences (Labmar - Ufal) and from the Laboratory of Environmental Geochemistry at IGDEMA - Ufal. For data on river levels, flows, rainfall, climatology, water quality and sediments, digital data from the National Water and Basic Sanitation Agency (ANA) website were analyzed through the HidroWeb Portal. For rainfall, the Hydrometeorological Database (BDHM) of the State Secretariat for the Environment and Water Resources of Alagoas (SEMARH – AL) was used. Therefore, when analyzing the TSI obtained, one can classify the Paraíba do Meio River with a eutrophic trophic state, in which the quality of its water underwent major changes in parameters such as Total Phosphorus (P) and Chlorophyll a, with phosphorus enrichment being determining factor for its current stage of eutrophication.