International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004
essentially, VI and BI have high correlation of negative.
After that, set the scaling of zero percent point and a hundred
percent point. Details in (A. Rikimaru, 1996)
> Scaled Shadow Index; SSI
The shadow index (SI) is a relative value. Its normalized
value can be utilized for calculation with other parameters;
The SSI was developed in order to integrate VI values and SI
values. In areas where the SSI value is zero, this corresponds
with forests that have the lowest shadow value (i.e.0%). In
areas were the SSI value is 100, this corresponds with forests
that have the highest possible shadow value (i.e.100%).SSI is
obtained by linear transformation of SI. With development of
the SSI one can now clearly differentiate between vegetation
in the canopy and vegetation on the ground. This constitutes
one of the major advantages of the new methods. It
significantly improves the capability to provide more
accurate result from data analysis than was possible in the
past.
> Integration process to achieve FCD model
Integration of VD and SSI means transformation for forest
canopy density value. Both parameter has dimension and has
percentage scale unit of density. It is possible to synthesize
both indices safely by means of corresponding scale and unit
of each
FCD=~VD*SSI+1-1 ©)
5. FOREST CANOPY DESITY MAP FOR STUDY
AREA
The degree of forest density is expressed in percentages: 10%
FCD, 20%, 30%, 40% and so on. The Fig.S indicates forest
canopy density map of the study area for ETM+ image.
0%
Figure 5. Forest canopy density map for ETM+ (2002).
For accuracy assessment and collected ground truth, the
distance between classes were changes to the form below:
Class!) Water & Cloud -W&C
Class2) No Forest =NF (0-5%density)
Class3) Low Forest = LF (5-40%density)
Class4) Middle Forest =MF (41-70%density)
Class5) Dense Forest =DF (71-100%density)
Figure 6 indicates this map with these classes.
37 Legend
Dens Forest
[. ]Low-Forest
[...]Middle-Forest
[.]NO-Forest
| MESI
Figure6. 4 classes density map.
Table 2 shows the confusion matrix, overall accuracy and
kappa coefficient, which is calculate for 2002 images.
NF LE MF DF Total U.A
(96)
CI 10328 1622 18 0 11968 86
C2 273 8163 3311 3 11750 69
C3 9 246 6852 1227 834 | 8222
C4 0 0 127 8984 9111 | 98.61
Total | 10610 10031 10308 10214 | 41163 | 41163
P.A 97.34 81.38 66.47 87.96
%
250
Table 2. Confusion matrix
Kappa Coefficient =0.78
Overall accuracy =83%
UA : User’s accuracy P A: Producer’s accuracy
6. Forest density & Area changes in the studied site
during 1991-1998
For change detection, the images should be taken at à
simultaneous date and season also, they should be
dereferencing exactly. Since the season for the 2002 image,
differs from 1991, so we use 1998 and 1991 images. They
have been dereferencing to 2002 image. Then we prepared
density map, using these two images for the years 91 and 98.
Fig 7 & 8 shows the forest density map for these years.
Internatio
BCE
*
sa
e
Figure7. |
Figure
Pixel size a
Since every
in the chan
changes. T
forest chan
density cha
Figure 9
The table 3