URBAN SPRAWL MONITORING IN BAMAKO FROM 1990 TO 2017 USING REMOTE SENSING DATA

Abstract

Our study was conducted on the city of Bamako, the capital of the Republic of Mali, to monitor the evolution of urban sprawl from 1990 to 2017. For this study, four multi-dated Landsat satellite images were used. From image processing, three classes were extracted to understand the phenomenon of urban sprawl: built-up area, non-built area, and water (river). From the analysis of the image processing results, it can be seen that the urban sprawl in Bamako during the study period has grown exponentially over the years; and has grown in the late periods. Urban sprawl was first important on the left bank of the Niger River before exporting to the right bank to be more important today than on the left bank. Urban sprawl was so important during this period that it consumed all the administrative space of the district of Bamako, and exported greatly to the surrounding rural municipalities. This shows the importance of urban sprawl in Bamako from 1990 to 2017; as shown in the results of expansion ratio compared to 1990, the area of built-up area increased 33.52% in 1998, 211.77% in 2006, and 400.40% in 2017, respectively.