Avaliação dos impactos socioambientais da agricultura na bacia do rio infulene: análise do processo de eutrofização

Abstract

Agricultural activity often takes place near water bodies such as rivers and lakes, and relies on the use of fertilizers to accelerate crop growth. However, the presence of these compounds at elevated levels in water bodies leads to eutrophication. This study aims to assess the socio-environmental impacts of agricultural activity in the Infulene River Basin, with emphasis on the eutrophication process. The analysis focused on the evaluation of the physical, chemical, and biological parameters of the water through laboratory tests performed at different points within the Basin. Among these parameters, the main indicators were the levels of agricultural nutrients, such as nitrogen (nitrates and nitrites) and phosphorus derived from the use of fertilizers. The results showed that phosphorus concentrations ranged from 0.52 mg/l to 6.21 mg/l, while nitrogen compound concentrations varied from 1.46 mg/l to 99 mg/l for nitrates and 2 mg/l to 5 mg/l for nitrites. These values exceed the maximum permissible limits established by Ministerial Diploma No. 180/2004 on Water Quality for Human Consumption. It is therefore concluded that agricultural activity increases nutrient concentrations at points where farming practices are more intensive, leading to eutrophication of the river. As mitigation measures, this study proposes the implementation of aquatic plant removal campaigns and the periodic and rigorous monitoring of nutrient levels in the water.