Modelagem da conservação das pastagens e seu impacto na qualidade hídrica a partir de quadrados mínimos parciais.

Abstract

Pasture degradation represents a socioeconomic and environmental problem to the balance of ecosystems. The disrespect for land use suitability that is associated with inappropriate management practices may intensify degradation processes, which may leave areas susceptible to erosion which is also an important source of degrada- tion of rivers and streams. With the advancement of cattle ranching in Brazil, there has been a significant increase in the areas occupied by pastures, so it is important to understand the contributing factors for the conservation of these pastures and the impact they have on water quality. The area of study selected was the EPA – Envi- ronmental Preservation Area along the Uberaba River, which is in Minas Gerais – Brazil.The diagnosis was made using cross tabulation and land use modeling through the partial least squares that indicated the relationship between the different factors studied and their contribution to soil conservation and water quality. The modeling carried out can help to orientate the protective efforts to the predominant factors in the conservation of pastures, with emphasis on the maintenance of organic matter indexes (w = 1.023), which is related to the stability of the soil aggregates that influence the susceptibility to erosion, to land use conflict (w = 1,000), in this way, the absence of conservation and cover practices has favored the transport of sediments by surface runoff. Pasture conservation influences surface water quality (β = 0.800), which highlights the oxidation potential (w = 0.743) and the potential hydrogen(w = 0.029).