From the preliminary experiment, we received suggestion that temperature information is useful for diagnosis of water stress of the vegetation. Then, we continued the measurement of water potential, reflectance and temperature change for two sets of sample trees of
Viburnum lantana by giving water to one set and cutting the supply of water to the other set. After the water shortage, water potential of the leaf was on the decrease from 12th day. On the other hand, temperature change of leaf was on the increase from 18th day, and NDWI obtained from reflectance was on the decrease from 30th day when the leaf is dying. Therefore, temperature information is more suitable and available for the early diagnosis of the water stress than NDWI.
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