The data from remote sensing and thematic data were 
integrated into a data base regarding the conceptual, logic and 
3. OBJECTIVES 
physical models to be used in a GIS. In order to resolve this problem a methodology was first Th 
conceived to take all the data in consideration: plurithematic, Tes 
Hence, queries on land use, administrative borders, superficial multisource and multidate. fac 
and underground water resources, geomorphology and climatic the 
factors were built to make out management planning scenarios It appeared that satellite data and GIS must be used to de 
necessary to a zone management. 
Consequently, the GIS used together with remote sensing is a 
very strong tool which helps the managers to undertake studies 
on information updating and evolution of phenomena using 
the now automated inventeries. 
2. POSITION OF THE PROBLEM 
The steppic area is situated in the arid and semi-arid region of 
the Mediterranean borders. It is the main source of livestock 
feeding but it is in the same time threatened by the land cover 
degradation as well as socio-economic desasters causing, 
hence, a deficiency in the need of the population which is 
concentrated in agglomerations 
Therefore, it is necessary to look for efficient methods and 
reliable information to study the evolution of the state of the 
countryside. These methods are used to identify the areas of 
first priority to an intervention. 
manipulate a big deal of information. 
The objectives of the study are : 
e the use of Landsat TM and MSS images to find out 
natural renewable resources in the arid and to understand 
how does the ecosystem behave. This step leads to : 
- Land cover map; 
- Changes map. 
e find out a methodology studying the grassland evolution 
e Conceive a physical data base making interrelations and 
intrarelations between the plurithematic and multisource 
data and manage them locally; 
e find out a methodology to integrate satellite data into a 
data base; 
e run a GIS in order to build a set of questions to analyse 
this data base. 
4. DATA USED 
In this study the plurithematic and multisource data were used 
and taken into consideration by the data base (see tablel). 
  
  
  
Table 1: table of physical data 
  
  
  
  
  
| DATA CAPTURE DATA SOURCE SCALE DATE 
i DEM Digitization Four (4) thematics maps 1/200.000 1960 
| | 
| Land cover map Treatment image (TM) resolution 1995 à 
| 30m : 
| Roads Digitization six (6) Topographics 1/100.000 1956 
maps ; 
Town ships border Digitization six (6) Topographics 1/100.000 1956 ; 
maps 
Drilling Treatment Numeric File 1995 
(X,Y) i 
| Hydrographic Network Digitization six (6) Topographics maps 1/100.000 1956 1 
Two Images (TM) CD Landasat 5 30m 17/05/1986 : 
08/04/1995 
Image (MSS) magnetic Landsat 1 80m 02/06/1976 
| Band 
Training Plot Treatment * Numeric File 1996 
(X.Y) 
Geomorphological map Treatment Numeric File 1987 
(X.Y) 
  
  
  
680 International Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998