Relations between a Commercial Soil Survey Map Based on Soil Apparent Electrical Conductivity (ECa) and Measured Soil Properties on a Morainic Soil in Southeast Norway

The use of noninvasive electromagnetic (EM) induction to measure apparent prole soil electrical conductivity (ECa) provides a time-and cost-effective tool to map within-eld variation in soil properties. Apparent electrical conductivity (ECa) shows the depth-weighed summarized effect of all factors inuencing EC in soil, and a range of chemical and physical properties have been indirectly determined by the EM-ECa method, such as soil salinity hazard (Williams and Baker, 1982), soil water content (Sheets and Hendrickx, 1995), claypan thickness (Doolittle et al., 1994), topsoil inorganic N content (Korsaeth, 2005a), and nutrient levels (Heiniger et al., 2003).