f.-F. Khreim and B. Lacaze: Land Cover Change Detection in the Mediterranean Area
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Table 1. Interpretation of additive colors in three date RGB-NDVI image.
Color
1977 1986 1993
Interpretation of change
observed
(Red) (Blne) (Green)
Black
N
N
N
no change (water, urban)
Dark grey
L
L
L
no change (low biomass)
Light grey
M
M
M
no change (medium biomass)
White
H
H
H
no change (high biomass)
Light pink
H
H
M
* decrease in 1993
Pink
H
H
L
**decrease in 1993
Magenta
H
H
N
***decrease in 1993
Yellow
H
L
H
**decrease in 1986; **increase in 1993
Orange
H
L
M
**decrease in 1986; *increase in 1993
Cyan
L
H
H
**increase in 1986 and 1993
Light blue
M
H
H
*increase in 1986 and 1993
Green
M
L
H
*decrease in 1986; **increase in 1993
Dark green
L
L
M
*increase in 1993
Light Green
M
L
H
*decrease in 1986; **increase in 1993
Dark green
L
L
M
*increase in 1993
Red
H
L
L
**decrease in 1986 and 1993
Legend: NDVI classes: N - No vegetation; L - Low vegetation density;
M - Medium vegetation density; H - High vegetation density;
*, **, ***: degree of change (NDVI slice units).
Table 2. Distribution ofNDVI classes over the 1977-1993 period (in % of the total terrestrial
pixels of the scene).
1977 1986 1993 (1993-1977)
Class 1: no vegetation
14.2
14.5
21.7
+ 7.5
Class 2: low vegetation density
23.1
20.2
23.4
+ 0.3
Class 3: medium vegetation density
32.7
35.3
29.1
- 3.6
Class 4: high vegetation density
30.0
30.1
25.8
- 4.2