Multiannual analysis of the quality of waters in the tax basin of the brazilian Pantanal

Abstract

The data from the monitoring programs, have been little used to support the decision making of the managers of the hydrographic basins. Several tools can be adopted, but it is essential that the first step is through discriminating analysis. This analysis allows the manager to distinguish, within a set of variables, which are the ones that can be chosen as indicators of impact processes (singularities) of those that are likely to be a long-term variable attribute in the (intrinsic) system. The objective of this study is to identify and evaluate the intrinsic structure and singularities of the water body, based on the physical, chemical and biological variables of water quality, in the Rio Vermelho Basin/MT, using long-term monitoring data (2006 to 2006). 2017), focusing on establishing a technical criterion for prioritizing conservation actions in the basin. The methodology consists of the use of multivariate statistical methods, factor analysis (PA) and principal component analysis (PCA). The results indicated that the statistical methods are efficient to rank the parameters, so that the parameters: color, chemical oxygen demand, total nitrogen, total coliforms, chloride, non-filterable residue, Escherichia coli, total phosphorus, turbidity, total residue have greater weight in the variance and are the characteristic variables of changes in the water body while: air temperature, water temperature; ammoniacal nitrogen; nitrogen nitrite, pH; dissolved oxygen, BOD, orthophosphate, medium flow; and nitrate, can be characterized by low variance as the intrinsic variables of the river, which are natural in the water body. The potential and limitations of the methodology and data are discussed. Considering the complexity of multiple uses of the basin, which include agricultural production areas, conservation units, SHPs, urban areas and indigenous lands, given the scenario of a trend of loss of water quality, it is recommended that the Rio Vermelho Basin be included as a priority in management and conservation strategies.