2 MATERIAL AND METHODS 
2.1 Study area and satellite data 
The study area is located in the Dasht-e Barm region (29? 33' 19" N, 51? 53' 16"E) located in the Zagros forests, Fars province, Iran. 
High spatial resolution multispectral imagery was acquired over the study area by QuickBird sensor on 1 August 2005. 
i cr, x : m i 
       
Figure 1. Illustration of images from ASTER (right image) yellow box and QuickBird (left image) showing study area of oak 
forest. 
The QuickBird data set was composed of a panchromatic image (450 — 900 nm) with a GSD of 0.6 m, and 4-band multispectral 
imagery with 2.4 m GSD. The four bands include: blue (450 — 520 nm), green (520 — 600 nm), red (630 — 690 nm), and near-infrared 
(760 — 900 nm). The image was georeferenced to UTM zone 39N, WGS84 datum. The ASTER imagery was obtained on 1 July 2005 
over the study area. Sub-images that covered the study site were extracted from the full images of the ASTER and QuickBird. Figure 
1 demonstrated both subset images of the study site 
2.2 Crown delineation 
According to flowchart presented in Figure 2 this study composed of two main stages. The first part consists of individual tree crown 
delineation using QuickBird imagery. Achieving automated individual tree crown delineation, panchromatic band of QuickBird 
imagery was fused with multispectral bands using the PCA fusion technique. This step has been done to increase the spatial 
resolution of multispectral bands while preserving the spectral properties. Individual tree crowns were delineated using SMAP 
(Sequential Maximum A Posteriori) algorithm. SMAP combines an approach of Gaussian mixture model for classes distribution, to 
maximize separability among the classes and specialize each spectral signature, with a hierarchical multiscale segmentation method 
for contextual classification. 
2.2.1Field data 
Individual tree crowns were collected in frequent field visits in 2005-06 using DGPS Leica GS20. About 40 sample plots were 
measured during these field visits. 
QuickBird data | ASTER data 
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Image fusion Pre-processing 
Automated delineation Different vegetation 
of individual tree crown indeces 
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Ground truth Correlation models > validation 
  
  
  
  
  
  
  
  
  
  
  
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