Observation of field variability in tsunami-affected paddy field by using on the go soil sensor

This study observed soil condition in a tsunami-damaged field. An on-the-go soil sensor mounted on rice transplanter was employed for field monitoring. Topsoil depth (TD) and soil fertility value (SFV) were used for field evaluation. A dataset of 17,017 samples for tsunami-damaged and 33,716 samples from on-damaged field were evaluated in this study. Results indicated that standard deviation of TD between tsunami and non-damaged fields showed very little differences. However, average SFV in the tsunami field was greater than three times higher than that of non-damaged field. Especially, high SFV (i.e. 1.2 mS/cm) was observed around the edge of field due to the salt removal operation by using mole drain.