Evaluation method for botanical-integrity of vascular plant, irrigating method to vascular plant, film electret sensor and film ECM array

A method for evaluating degree of botanical-integrity in vascular plant, comprising:

• generating a burst acoustic wave of a wavelength longer than a diameter of an axis of vascular plant assigned as a measuring target, by an acoustic vibrator fixed to the axis;
• measuring a guide wave generated by the burst acoustic wave and propagated through a whole of the axis, by an elastic wave reception sensor fixed to the axis;
• determining a measured sound velocity and a measured sound velocity attenuation rate of the guide wave, from the measurement;
• and
• comparing a reference sound velocity and a reference attenuation rate of a guide wave propagated through an entire axis of a reference vascular plant in a healthy botanical state with the measured sound velocity and the measured attenuation rate, respectively, the reference vascular plant is equal in species to the measuring target, the reference sound velocity and the reference attenuation rate is pre-examined with the reference vascular plant,
• wherein a water state of the measuring target is evaluated.

A method for irrigating vascular plant, comprising:

• measuring an occurrence frequency of elastic waves generated by cavitations in vascular tissues in vascular plant, before and after a change in water stress to the vascular plant, respectively, by an elastic wave reception sensor fixed to an axis of the vascular plant;
• calculating a change rate of the occurrence frequency, from the occurrence frequency of the elastic wave measured before and after the change, respectively;
• determining whether or not an embolism of the vascular tissue arrives at an unrecoverable level, from the calculated change rate;
• and
• determining an irrigation timing and an irrigation quantity to the vascular plant, using the determined result as an index.

A method for irrigating vascular plant, including:

• attaching an acoustic vibrator and an acoustic receiver to an axis of vascular plant having an annular vascular tissue, and measuring an attenuation rate of an acoustic wave propagated through the vascular tissue and then determining an measured attenuation rate;
• dividing the measured attenuation rate by a value of a reference attenuation rate so as to calculate an attenuation rate ratio, the reference attenuation rate is determined by an attenuation rate of the acoustic wave propagated through the vascular tissue measured in a case that a sufficient irrigation is carried out to the vascular plant in advance;
• and
• determining an irrigation timing and an irrigation quantity to the vascular plant, with the calculated attenuation rate ratio as an index.