Qualidade da água dos rios no Brasil: uma abordagem socioambiental

Abstract

This dissertation addresses the interaction between economic growth, basic sanitation infrastructure, environmental legislation, and river water quality in the Brazilian context. Through three distinct studies, we investigate how economic and population growth influence water pollution, the role of environmental legislation in improving sanitation infrastructure, and the impacts of these variables on the incidence of waterborne diseases. The first study examines the relationship between economic growth, measured by Gross Domestic Product (GDP) per capita, and river pollution, using Biochemical Oxygen Demand (BOD) as an indicator of pollution. Conducted in 950 Brazilian municipalities in 2020, the study reveals that more developed regions tend to face higher levels of pollution due to concentrated industrial and urban activities. On the other hand, less developed areas face challenges in improving basic sanitation infrastructure, contributing to water degradation. The study identifies turning points in the relationship between GDP per capita and river pollution, suggesting specific stages of development that require environmental preservation measures. The second study investigates the relationship between Biochemical Oxygen Demand (BOD) and economic and population variables from 2008 to 2020 in 73 Brazilian municipalities. Using techniques such as the Pedroni Cointegration Test and the Granger causality test, the study shows a strong long-term relationship between BOD and agricultural GDP per capita, industrial GDP per capita and population. The results highlight the significant influence of industrial and agricultural production and population growth on river water quality, suggesting the need for policies that promote sustainable economic growth and effective water resource management. The third and final study investigates the influence of municipal environmental legislation and basic sanitation infrastructure on river water quality and the incidence of waterborne diseases in 1,048 Brazilian municipalities in 2020, using Structural Equation Modeling (SEM). The results indicate that improvements in basic sanitation infrastructure reduce waterborne diseases and are associated with reduced water pollution. River water quality is influenced by stricter environmental legislation, which mediates the relationship between sanitation infrastructure and public health. The study highlights the importance of integrated policies that promote sustainable development and efficient management of water resources. The conclusions of these three studies highlight the need for investments in basic sanitation infrastructure, especially in less developed areas, and for environmental regulations that balance economic growth with environmental conservation. The results have implications for the formulation of public policies aimed at sustainable management of water resources and the socioeconomic development of the country.