PROBLEM TO BE SOLVED: To specify a farm field sensor to be displayed on a mobile terminal and to check farm field information easily.SOLUTION: Included are: farm field sensors which acquire positional information of their placed positions and information of their placed farm fields, and transmit the positional information and the farm field information； a data sensor which is configured to be able to receive the positional information and the farm field information from the farm field sensors, store individual information of each of the farm field sensors in association with the positional information and the farm field information, and transmit the associated individual information of the farm field sensors, positional information, and farm field information； and a mobile terminal which acquires positional information of its current position and terminal posture bearing information, transmits the positional information, and receives the individual information of the farm field sensors, positional information, and farm field information transmitted from the data sensor. The farm field sensor included in a video captured by an imaging device provided to the mobile terminal is specified based on the positional information of the farm field sensor and the positional information of the mobile terminal, and the farm field information acquired by the specified farm field sensor is displayed over the video on a display device in a superimposed manner.SELECTED DRAWING: Figure 7
