Dependence of Soil Apparent Electrical Conductivity (ECa) upon Soil Texture and Ignition Loss at Various Depths in Two Morainic Loam Soils in Southeast Norway

The use of sensor techniques provides a time-and cost-effective alternative to traditional soil sampling and laboratory analyses, in order to monitor spatial and temporal soil variation. One sensorbased, noninvasive technique is to measure apparent electrical conductivity (ECa) of a soil prole by means of an electromagnetic (EM) induction approach. The device selected for the EM measurements in this paper was the Geonics EM38 (Mississauga, ON, Canada; www.geonics.com), which is the EM-ECa sensor most often used in agriculture (Sudduth et al., 2001). The device may be operated in one of two measurement modes that give an effective measuring depth of either 0.75 or 1.5 m.