The importance of integrating metadata into GIS: the case study of the geographic information system of the city of Khouribga (Morocco).

Spatial data are a model of the real world that allows the use of information for further computer analysis and graphics. However, to assure a correct use of the data, it is necessary that all criteria for collecting and implementing of data be amply documented. Since producers and users of geo-spatial data manage a great quantity of information, an appropriate documentation will guarantee a complete and accurate knowledge of all possessed data, thus assuring the correct management of their production, storage, use and updating. For this purpose, the use of standard management criteria seems essential: the aim is to establish consistent procedures for the description of spatial data sets. One of the most important GIS standards is metadata. Metadata allow a complete description of a set of data, thus enabling the users to comprehend the limitation and collecting criteria while evaluating the possibilities and modes of use for specific purposes. In projecting the GIS of the city of Khouribga - carried out in the sphere of the diagnostic phase of the SIGEK 2000 project: “amélioration des capacitès techniques et de gestion locale pour la mise en place d'un système de gestion environnementale intégrée dans la ville de Khouribga (Maroc)", financed by the EU - a particular attention has been given to the organisation of the database documentation by adopting the CEN TC287 Standard of the European Technical Committee. The objective was to create an information system of the city and its surroundings to be used by the various technical bureaux of the Khouribga municipality. Through this project the city has acquired a flexible and dynamic tool for land management and planning of all environmental aspects regarding an area with a strong industrial and human expansion. This area has been chosen as a model due to the several environmental problems that it presents. The city and its surroundings are characterised by the presence of intense activities for the exploitation of phosphatic minerals and also by large quantities of phosphatic waste, which, beyond altering the landscape, are a source of environmental pollution to which the local authorities want to find a solution. All the data sets (either initial or produced during the project) have been associated to the respective metadata created during the construction of the database; all output data have been continuously updated. This has avoided eventual posterior reconstruction of the information contents, thus relieving the implementation process of a great burden