EVALUATION OF HYDRAULIC CONDUCTIVITY IN TWO LAND USES SOIL IN CENTRAL BRAZIL

Abstract

Evaluation of the hydraulic conductivity in soil of different use — agricultural cultivation and undisturbed native Savannah — was performed, in order to verify the influence of intense agricultural activities on water infiltration in soils and, consequently, aquifer recharges. For this purpose, the experimental design involved the determination of saturated hydraulic conductivity using the Guelph permeameter and double-ring infiltrometer. Tests were performed on large area covering five states in Central Brazil, where the agriculture has been intense. Evaluated by parametric statistics, the hydraulic conductivity values in farms cultivated areas proved to be statistically different and 4.5 times lower compared to those ones obtained in savannah. These results showed that changes in soil structure resulting from management practices in crop areas significantly affect the hydraulic conductivity of the superficial portions and, therefore, the water infiltration, responsible for the aquifer recharge in that area. Additionally, it was found that the infiltrometer provided statistically different values of hydraulic conductivity and 2.2 times higher than those ones obtained with Guelph permeameter.