Soil Water Measurement Comparisons Between Semi-Permanent and Portable Capacitance Probes

The objectives of this study were to compare and characterize the soil water measurement responses using the EnviroSCAN semi permanent multisensor capacitance probes (MCP) and the Diviner 2000 (D2k) portable capacitance probe.Both probes are manufactured by Sentek Pty. Ltd., Stepney, South Australia. Comparative soil water measurements were made using the portable D2k and the MCP probes at three field sites where 48 polyvinylchloride (PVC) access tubes were previously installed and being used to near-continuously monitor soil water content at four or more depths. The D2k and MCP soil water sensing data were highly correlated values (R² > 0.98), but the D2k water contents averaged about 5% more than the corresponding MCP values. As a result of this high correlation we were able to transform the D2k readings so that the two probes gave essentially the same water content values when measured as the same time and position.