Study of flow in vadose zone from electrical resistivity surveys

Abstract

Among the Indirect methods applied to environmental monitoring, electrical resistivity has played an important role in accessing water flow In the non-saturated zone of the soil and, consequently, aquifer recharge, This work evaluates the influence of some pedo-geomorphologic properties in the Infiltration and percolation of water through the superficial soil horizons by means of multitemporal electrical resistivity sections. The experiments were carried out In two areas of distinct pedogeomorphological characteristics developed on the crystalline basement of southeastern Brazil. The first Is situated In a hollow-shaped slope where lixisols predominate; the second, in a nose-shapsd slope where well-developed soils (ferralsols) predominate. The results proved the efficiency of the electrical resistivity method to delimit percolation of tropical soils, even when subtle differences are found in the hydraulic properties of the soil, It was also possible to establish that in the nose slope percolation Is faster than in the hollow. © 2008 Sociedade Brasileira de Geofísica.