Temporal and seasonal landscape diagnosis and anthropogenic impacts: Environmental assessment of a watershed using the Rapid Assessment Protocol

Abstract

The growing concern about the degradation of water resources, exacerbated by climate change and accelerated urbanization, has driven institutional and legislative changes. This study aimed to evaluate streams located in the São Thomas River basin, in the municipality of Rio Verde, Goiás, Brazil, using the Rapid Assessment Protocol, highlighting the main pollution points and their characteristics to visually and landscape characterize the conditions of the streams during dry and rainy periods. Variability in water quality was observed among the sampling points, with Sapo 2, Sapo 7, and Barrinha standing out for their superior conditions, while Rocha, Buriti, and São Tomás showed less favorable conditions with higher pollution levels. Visually, variations in parameters were noted between dry and rainy periods. However, the results of the paired t-test did not indicate statistically significant differences between the dry and rainy periods (t = -2.0156, p-value = 0.0786). This suggests that, although visual indications of seasonal changes exist, the statistical evidence does not support significant differences in water quality between the analyzed periods. Therefore, while seasonal fluctuations are visually evident, the statistical analysis does not confirm their significance. These results underscore the importance of seasonal studies to understand variations in water quality over time and to support environmental management policies that promote the sustainability of water resources and ensure quality water for local communities.