Selection of Suitable Soil Moisture Sensor for Clay Soil

Accurate soil volumetric water content (VWC) measurement is pivotal for precision agriculture. Soil moisture sensor technology is crucial in this context, providing essential VWC data for evaluating information obtained through remote sensing and data assimilation. As the world continuously advances precision agriculture, enhancing the accuracy of VWC measurement becomes paramount. In this study, the researchers investigated the suitable soil moisture sensor for optimal agricultural application on clay soil. Five different kinds of soil moisture sensors classified into three resistance-based and two capacitance-based were analyzed. The parameters assessed in the study were precision, linearity, and accuracy. These variables are measured using the raw readings of each sensor; precision was determined using deviation value, linearity was identified using the linearity regression graph, and accuracy was obtained by comparing the expected and actual values of VWC. Each sensor parameter was compared to determine which stands out among the five soil moisture sensors. From the collected data, STEMMA was the most suitable soil moisture sensor for clay applications among the five, with a linearity coefficient of 0.9767, deviation values below 2 (high precision), and an average accuracy of 90.8 percent across five VWC levels.