Non-invasive estimation of root water content by ground-penetrating radar

Root water content is vital for understanding the response of plant water use to environment. It is an urgent demand for many disciplines to seek a non-invasive method of monitoring root water content in the field. This study proposed to use the root reflection data of ground-penetrating radar (GPR) to estimate root water content. Two GPR-based models, one empirical model and one semi-empirical model, were established, and their effectiveness was verified in the carefully designed simulation and field experiments. Results confirmed the good performance of both models in estimating root water content, which shed new insights on long-term monitoring of root water content in the field.