The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
3.4 The red edge feature of the canopy and leaf for spr- 
wheat 
Like most of the green vegetation, there are “double peak” or 
“multi-peak” phenomena for the spr-wheat at growth stage, 
just the “double peak” feature is not notably because of the im 
pacts of the soil spectral at the beginning of the growth stage, 
and it disappeared until the wheat mature and the leaf turn to 
yellow. 
0. 007 
| 0.006 
| 0.005 
u ' e 0. 004 
5 ° o.oo3 
s ^ 
2, 0.002 
.g 
^ 0.001 
0 
660 680 700 720 740 760 780 
waveband(nm) 
- - - - jointing stage booting stage -heading stage 
—x—filling stage milkinem stage -ripening stage 
Figure.4 the first derivative spectra of canopy red edge for 
spr-wheat in different stage 
735 
J 730 
0 
■{? 725 
Q 
■g 720 
| 715 
o 710 
■2 705 
o 700 
Q. 
| 695 
690 
jointing booting heading filling milking ripening 
growth stage 
Figure.5 The position of the red edge change of canopy for spr- 
wheat in different four densities in different stage 
From the Fig.4 and Fig.5, the red edge position of the canopy 
reflectance is at 700~730nm region during the growth stage, 
Additionally, by the grown stage from the joinging stage to 
heading stage, there were “red shift” phenomena weakly and 
from heading stage to ripening stage, there were “blue shift” 
phenomena remarkably, and for the X red , D X red and Sred of 
the canopy and leaf spectra are decrease from jointing stage to 
ripening. This shows that the X red, D X red and Sred are the 
signal of the wheat growing, it also shows that the red edge po 
sition maybe the indicator for the vegetation in stress status. 
table. 1. 
From Fig.6,Fig.7 and the table.2, The leaf area indices 
(LAI),the above ground fresh biomass, above ground dry bio 
mass , plant height, chlorophyll are significantly correlative to 
the spectral Vegetation Indices: normalized difference vegeta 
tion index(NDVI), soil adjusted vegetation index (SAVI), 
ratio vegetation index (RVI) »difference vegetation index (DVI) 
and perpendicular vegetation index (PVI), etal, and the rela 
tionship of PVI with plant height and above ground fresh- 
biomass-weitht(FW) is the best(R=0. 
563,P<0.01;r=0.685,P<0.01), and the LAI have the best rela 
tionship with DVI (r=0.694,P<0.01) and the relativity are the 
best between the spectral index(R670/440) and the chlorophyll 
among the selected spectral index(r=-0.846,P<0.01), X red and 
plant chlorophyll content are good correlation. This indicated 
that some right spectral variables would be used to estimate the 
LAI, ADM, the PH and chlorophyll for spr-wheat. Furthermore, 
the correlation of the spectral index and the biochemical prop 
erties of vegetation are effected by the different cultivars. 
Figure.6 the relationship between the spectral indices and the 
LAI 
3.5 The relationship of the hyperspecral data and the 
biophysical Parameters 
For the sake of analyzing the correlations among the ground 
dry weight (ADM), the plant height (PH) and the hyperspectral 
variable, we selected the rate of the special band and the red 
edge parameter to built the following spectral variable listed in