Measurement of soil water content in a hyper‐arid environment using time‐domain reflectometry sensors

Abstract

AbstractTime‐domain reflectometry (TDR) sensors have been widely used in many fields for measurement of soil water content. However, few TDR sensors have been used in a hyper‐arid environment (e.g. less than 0·05 m3 m−3), and such sensor applicability is not yet confirmed. In this study we examine θ − t and θ − εbulk relations and temperature dependency for natural sand and glass beads in a laboratory using commercially available TDR sensors. As a result, this study clarifies that TDR sensors are applicable even in a hyper‐arid environment when calibration was properly made. We also focus on a specific range of soil water content, which leads to a highly precise calibration equation. Copyright © 2005 John Wiley & Sons, Ltd.