Predicting urban growth of a developing country city using a statistical modeling approach

Rapid population growth is pushing African cities to unprecedented sizes. The negative social and environmental consequences of the uncontrolled urban expansion have been documented. The purpose of this project was to develop appropriate databases to study the temporal land use changes in urban expansion and predict future urban growth for the city of Niamey, Niger. Land use transition was obtained from satellite imagery of 1973, 1988, and 2001. Spatial layers of driving forces of urban growth were derived from a digital orthophoto and extensive GPS mapping. A multinomial binary logistic regression was used to derive urban transition probabilities and simulated maps of future urban growth were subsequently generated. This study suggests that urbanized areas of the city will increase by 65.64 km² between 1988 and 2010 and the population will increase from 397,437 to 2,063,894. The implications will include overcrowding, destruction of scarce farmlands and deforestation of the surrounding plateaus. Deforestation of the fragile uplands results in the generation of uncontrolled runoff that provokes serious erosion. Sediment carried in the runoff creates unproductive alluvial fans at the footslopes of the plateau.