QUALIDADE AMBIENTAL DAS NASCENTES DO RIO PARAIM, EXTREMO SUL DO PIAUÍ

Abstract

The small flows give rise to water bodies, that through their multiple uses, contribute to the satisfaction of the basic vital needs of animals, plants and ecosystems. The headwater areas execute an important role in maintaining the environmental quality of the watershed. Therefore, it is indispensable that these regions have an effective conservation policy. Thus, the objective of thisstudy was to determine the environmental quality of the Paraim headwaters , emphasizing the physical-chemical and biological quality aspects of the waters and characterization of the local environmental conditions through macroscopic assessment. Visits were made in seven permanent headwaters of the Paraim river and, with the macroscopic assessment, it was possible to identify the impacts observed in the headwaters and permanent preservation areas, access conditions, proximity to rural centers and types of uses of headwaters. The physical-chemical and microbiological parameters of the water were measured and compared to Resolution No. 357/2005 of (National Environment Council (CONAMA) and Water Quality Index (WQI). The macroscopic assessment of the headwaters demonstrated 57.1% of the headwaters were evaluated in "great" or "good" situations and only a single headwater was classified as "terrible". The determination of the WQI of the headwater resulted in values ranging between 59 and 86 in the dry season; and between 56 and 89 in the wet season. Thus, all the headwaters evaluated presented WQI satisfactory ("good" or "great"). With the evaluation of the water quality, was possible to observe the relation between the quality parameters, as well as the influence of these parameters in headwaters macroscopic characteristics. Therefore, the obtained information indicates, althoughgood water quality, the assessment of the environmental situation of the headwaters alerts to the need for future strategies, whith aim on planning of land use and environmental management of watersheds.