Ebrahim, Mostafa Abdel-Bary 
In order to be able to obtain quantitative numerical results, and to be able to judge about the accuracy of results that 
obtained by the different processing techniques, the extracted reclaimed areas by each technique were compared with the 
actually applied one in the test area. The results of this step are given in Table 2. 
  
  
  
  
  
  
  
  
  
  
Information source The identified reclaimed area (square meters) 
1992 1995 1998 
Field reports 348600 1680000 4200000 
Composite image from stretched bands 390000 1926800 3953600 
Normalized Difference Vegetation Index | 17200 154000 222000 
Unsupervised classified image 458400 2762400 5060800 
  
  
Table 2, The identified reclaimed area by different techniques 
From Table 2 it can be realized that the information obtained from composite image that constructed from the stretched 
bands give the most accurate results (about 88 96). The accuracy of the results that obtained by unsupervised 
‚classification is about 61 %, due to the interference of other classes (desert areas) with the reclaimed areas. As a result of 
visual interpretation, one can realize that the results obtained by NDVI represent the vegetated areas only while the other 
method represent the vegetated areas in addition to the prepared land for cultivation (N. B. The data obtained from field 
reports include such land). The percentage of actually vegetated ground to the total prepared land for reclamation can be 
determined by from the ratio of area given by NDVI to the area given by composite image from stretched bands (or that 
give by unsupervised classification). 
The technique of constructing composite images from the stretched bands was applied to the second study area which 
contain scattered reclaimed land. The composite images of this are given in Plates 10, 11, and 12 for the images of 92, 
95, and 98 respectively, and the composite images that constructed from the stretched bands are given in Plates 13, 14, 
and 15 for the images of 92, 95, and 98 respectively. The extracted reclaimed areas are listed in Table 3. 
  
  
  
  
  
  
  
Year 1992 1995 1998 
Reclaimed area 6000 21600 47600 
(square m) 
  
Table 3, The identified reclaimed land in the second test area 
5. CONCLUSION 
This study proved that the digital analysis of high spatial and spectral resolution SPOT multispectral images, 
with computer-aided visual approach, is a valuable tool for accurate detecting and locating of the new 
reclaimed areas. Unsupervised classification and simple thresholding of the image bands were found suitable for this 
purpose, under the irrigation and wither conditions in the Egyptian deserts.. According to the obtained results one 
can conclude that, SPOT satellite multispectral image proved to be one of the most important tools for regular 
evaluation of the reclamation projects that taking place nowadays in the Egyptian deserts. 
6. REFERENCES 
Austin, S., 1992. Application of Remote Sensing to Forest Assessment, Forest Land Cover Inventory and 
Change Detection., Remote Sensing & Natural Resource Management, Proceedings of the Fourth Forest 
Service Remote Sensing Applications Conference, Florida, April 6-11, 1992. 
Evans, D., etl 1992. Landsat Thematic Mapper Data for Development and Interpretation of Vegetation 
Information on the Kisatchie National Forest, Forest Land Cover Inventory and Change Detection., Remote 
Sensing & Natural Resource Management, Proceedings of the Fourth Forest Service Remote Sensing 
Applications Conference, Florida, April 6-11, 1992. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 387