Chemical and biological monitoring of water quality on a hydrographic basin in the State of Santa Catarina
The inappropriate destination of urban effluents, deforestation along the banks of watercourses, expanding agricultural activities, as well as the lack of public management plans for the prevention and adequacy of the use of urban rivers, compromise the efficiency of basic sanitation services and consequently the health of the population. The objective of this research is to monitor the water quality of the Itajaí-Açu river, the largest watercourse in the Itajaí hydrographic basin, located in the State of Santa Catarina, based on the seasonal chemical and biological indicators, in addition to verifying the statistically significant difference between the sample points. For this purpose, five collection points were allocated along the river, for the aforementioned indicators, in the seasons, spring and summer (2019); autumn and winter (2020), totaling 80 samples. To verify the statistically significant difference between the sample points, the Statistical Software R, version 3.6.3 was used. The results pointed to the chemical and biological contamination along the entire length of the Itajaí-Açu river, regardless of the seasonal aspect. There is an urgent need to implement Municipal Basic Sanitation Plans in all the municipalities that are part of the Itajaí watershed. The absence or precariousness of a planning instrument for the provision of public sanitation services in the municipalities, in addition to violating the legal principle of human dignity of access to clean water and adequate sanitation, contributes to the increase of the environmental degradation of the territory as well as the health of its population.