Ebrahim, Mostafa Abdel-Bary
Mapping of Reclamation Rate in the Egyptian Deserts
Using SPOT Satellite Images
by: Dr. Farrag Ali FARRAG ' and Dr. Mostafa Abdel-Bary EBRAHIM ?
! Assistant Professor & * Lecturer
Civil Engineering Dept.
Faculty of Engineering
Assiut University
Assiut, Egypt.
1 2 .
farrag@acc.aun.eun.eg & “ebrahim@acc.aun.eun.eg
KEYWORDS: Agriculture, Change Detection, Image processing, Remote sensing, SPOT
ABSTRACT
In this study temporal multispectral SPOT satellite images were examined for accurate mapping of the
reclaimed areas under the irrigation and wither conditions in the Egyptian deserts. A combination of image
interpretation, image thresholding, vegetation indices and unsupervised classification techniques were
applied. Three SPOT images of the same area (captured in 1992, 1995, and 1998) were processed with
emphasis on detecting the changes at a small area as a test area where a governmental reclamation project is
taking place. The detected increase in the reclaimed area was examined against the actual applied one. The
proved processing technique was applied on another area where some scattered reclamation process is
carried out by private agencies.
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. Accordingly, such technique can be applied for regular evaluation of the reclamation rates
that taking place nowadays in the Egyptian deserts, such as Toshika project in upper Egypt.
1. INTRODUCTION
Reclamation of desert is one of the major tasks nowadays in Egypt. The reclamation is carried out mainly in
the desert areas for cultivation purposes in order to fulfil the needs of the high population growth. The
reclamation rates need to be measured continuously and to be examined against the original planes.
Experience has demonstrated that collection and compilation of data, for such purposes, using traditional
techniques is costly and time consuming. The use of high resolution satellite images which is both repeated
very frequently and also employs computer processing can be an alternative data capture tool for accurate
mapping of the cultivated land and for determining the reclamation rates (see eg, [Evans etl (1992), Austin
(1992), and Genong (1996)]). On the other hand applying automatic detection techniques reduce the time
needed for obtaining accurate information about reclamation process.
A combination of image interpretation, image thresholding, vegetation indices and unsupervised
classification techniques was used for analyzing temporal multispectral SPOT images. The actually applied
reclamation in a test area was used as a reference to examine the results obtained by these image processing
techniques. The proven processing technique was applied on other area (Wady El-Asuty) where some
scattered reclamation processes are applied by private agencies.
2. STUDY AREAS AND DATA
The reclamation process was analyzed in two study areas. The first area belongs to Assiut cement factory in the western
desert, about 17 km to the west of Assiut City (Egypt). The reclamation in this area was controlled properly, where the
information about the reclamation rate is available. This area was considered as test area where the actually
applied reclamation in this area was used as a reference to examine the results obtained form SPOT images.
The second one is in Wady El-Asuty, about 30 km from Assiut city in the eastern desert. Wady El-Asuty represents
382 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.