La Détection Du Changement De L'Étalement Urbain Au Bas-Sahara Algérien : Apport De La Télédétection Spatiale Et Des Sig. Cas De La Ville De Biskra (Algérie)

Nowadays, urban sprawl is one of the major problems facing the Algerian Low-Sahara oases. Monitoring and understanding its spatial evolution remains an essential step for any sustainable development project of the oasis city. Local authorities do not have relevant and updated tools for effective management and spatial planning. Remote sensing and Geographic Information Systems (GIS) provide opportunities to overcome these difficulties. The present study consists in application of a change detection technique to map and quantify the spatiotemporal sprawl of Biskra City (Algeria), during the period 1985 - 2000, using three Landsat images acquired in 1985, 2000 and 2015. The post-classification comparison of land use and land cover maps has revealed a remarkable growth in the built-up areas going beyond the municipality's boundaries, in conurbation with the agglomeration of Chetma, against a progressive decline of the palm grove. It has undergone a continue process of fragmentation and conversion of its surface by the uncontrolled urbanisation, leading to the loss of the original oasis identity distinguishing this city. The main aim of this paper is to highlight the urban sprawl process and its spatial land use and land cover modifications. This study also shows the utility of change detection methods and Geographic Information Systems for monitoring the urbanisation patterns and assessing their impacts on oasis ecosystems.