Evaluation of water stress on a crop using the portable hyper spectral imager
2.Study area and experiment
This research study area is Field Production Science Center in the University of Tokyo, Tanashi
city, Tokyo. This area has warm moisture climate.
We adopted following experiment for direct measurement to vegetation. Amount of soil water
was measured by Profile Probe type PR1 [Delta-T Devices Ltd, Cambridge, UK], SPAD value
by SPAD-502 [Minolta Camera Co., Osaka, Japan], maximum water potential by Model 670
pressure chamber instrument [PMS Instrument Co., USA].
For indirect measurement, hyperspectral imeger which was developed by Yasuoka lab,
University of Tokyo was adopted. Specification of this imeger is shown in Figure 1,Figure 2.
Fig. 1. Specification of Hyperspectral imager
Fig. 2. Hyperspectral imeger
3.Methodology
The method of evaluation of water stress is described in this section. Figure 3 shows this
research flow. In this research, we set up two cases for detecting spectrum of vegetation water
stress. One case is given water stress by replant and non-water. Another case is not given by
affusion which is giving water.
Measurement is done every hour, total 4 hours.
Fig.3. Research flow
