Study on Irrigation Model Based on Plant Ultrasonic Acoustic Emissions

Produced by cohesion between water molecules or adhesion to the conduit wall, the plant cavitation is accompanied by the vessel walls vibration which is the indicator of the water stress. The ultrasonic acoustic emissions (UAEs) are used to detect the plant cavitation events which are the transmission of vibration. The UAEs could be detected in ultrasonic frequencies between 100K Hz and 1 MHz. The PCI-2 data acquisition (DAQ) equipment and R15 sensors are used to improve the precision of cavitation detection. When the water stress and dehydration gets heavier, the UAEs rate gets higher. Use the tomato practice data with the empirical deduction under the modern greenhouse conditions, the UAEs and Transpiration Index (UAETI) and the UAEs Irrigation Index (UAEII) irrigation model are draw from the relationship between transpiration and UAEs. UAETI can be used to analysis the transpiration, and UAEII can be used to analysis the irrigation time. It is better to use UAEs technique to carry out automatic and precise irrigation for the plant and to improve the effect of Water-saving irrigation.