Environmental quality of the Paraim River springs, far south of Piauí

Abstract

The small flows of runoff give rise to water bodies which, through their multiple uses, contribute to satisfying the basic vital needs of animals, plants and ecosystems. Spring areas play an important role in maintaining the environmental quality of the basin. To this end, it is essential that these areas have an effective conservation policy. The aim of this study was to determine the environmental quality of the Paraim River's spring areas, emphasizing the physical-chemical and biological quality of the water and characterizing local environmental conditions through macroscopic assessment. Visits were made to seven of the Paraim River's perennial springs and the macroscopic assessment made it possible to identify the impacts observed in the springs and permanent preservation areas, access conditions, proximity to rural centers and types of use of the springs. The physical-chemical and microbiological parameters of the water were assessed and compared with Resolution 357/2005 of the National Environment Council (CONAMA) and the Water Quality Index (IQA). The macroscopic assessment of the springs showed that 57.1% of the springs were rated as "excellent" or "good" and only one spring was rated as "very bad". Determining the WQI of the springs resulted in values varying between 59 and 86 in the dry season and between 56 and 89 in the rainy season. This shows that all the springs evaluated had satisfactory WQIs ("good" or "excellent"). The assessment of water quality made it possible to observe the relationship between the quality parameters, as well as their influence on the macroscopic characteristics of the springs. In this way, the information obtained indicates that, despite the good quality of the water, the assessment of the environmental situation of the springs warns of the need for future strategies aimed at planning for land use and environmental management of micro-watersheds.