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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B-YF. Istanbul 2004 
4. ANALYSIS AND RESULTS 
4.1 Analysis of different vegetation indices 
In the multitemporal dataset, five different vegetation indexes 
were performed and analysed as different band combinations by 
overlying in different RGB layers (Figure 3). As can be seen 
from the figure, the changes in vegetation biomass through the 
years were easily observed. In the multitemporal NDVI images, 
the black colours represent the areas having no vegetation in the 
years overlaid in RGB. These areas were mostly roads, urban 
areas and rivers. 
NINOS a. 
  
Figure 3. Multitemporal NDVI image 
(R: 1993 NDVI; G: 2003 NDVI; B: 1987 NDVI) 
For the ancillary information related to the different crops in the 
area, the 1993 crop plant sketch gathered from the Türkgeldi 
Production Farm was used. 
In this area, there are two main plantation seasons for sunflower 
and wheat crops in a year. The sunflower crops are generally 
planted both in April/May or June/July and harvested in 
June/July or August/September, respectively. On the other hand, 
the wheat crops are planted in the October/November and 
harvested in May/June. Because of having same plantation 
characteristics, barley and wheat crops had nearly the same 
vegetation index values in the dates of the images acquired 
(May/June). However, this was the opposite for the sunflower 
fields. Generally lower values were observed depending on the 
different plantation time with the others. 
As main crops, sunflower (blue colour), wheat (yellow colour) 
and barley (green colour) were selected and shown as different 
ROIs (Figure 4). Maximum values of these regions for different 
vegetation indices were computed for each year and evaluated 
graphically in Figure 5 through 9. 
183 
  
hf ( 
SVI 
  
  
( 
| 
A 
  
1987 1993 2000 2003 
Year 
Sunflower =  * Wheat ===== Barley 
Figure 5. Simple Vegetation Index results. 
200 Di m 
150 > : oe 
  
  
  
2 100 "m - 
0 R gU 
50 
0 
1987 1993 2000 2003 
Years 
“Sunflower =  * Wheat "-** Barley 
Figure 6. Difference Vegetation Index results. 
NDVI 
  
0,8 | 
_ 08 — Ne | 
& 04 — at C | 
0,2 
  
  
1987 1993 2000 2003 
S 
Year 
Sunflower =  * Wheat "S Barley 
Figure 7. Normalised Vegetation Difference Index results.