Development of empirical models for analysis of subsoil agricultural parameters from resistivity measurement in a basement complex terrain

Abstract

ABSTRACT Soil electrical resistivity measurements and soil properties determination were carried out at an arable plot located within the Federal University of Technology, Akure, Ondo State. This was with a view to establishing relationship between in-situ soil resistivity and selected topsoil properties in a typical basement complex environment. Electrical Resistivity was measured from the soil surface at 0 to 50 cm soil depths using Wenner Array. Electrode spacing of 130 cm (1.3 m) was utilized. Soil samples were collected to a depth of 50 cm at the mid points of 2 m by 2 m cell. These were analyzed for properties that include: moisture content, particle size analysis, Organic Matter (OM), pH and electrical conductivity. The regression analysis plots show that ER correlate significantly to soil properties, with coefficient of correlation of 0.90 for MC, 0.63 for SC, 0.74 for CC, 0.57 for OM, 0.94 for EC. Except for SC and PH that shows a non-significant correlation of 0.52 and 0.30 respectively. Validation of the derived empirical model gives a coefficient of correlation between the observed and predicted result as 0.94 for MC, 0.74 for OM, 0.93 for EC, 0.79 for SC, 0.94 for silt content, 0.52 for clay content and 0.48 for PH. The study concluded that electrical resistivity measurements could be used as a rapid tool for obtaining the selected topsoil properties.