Analysis of spatio-temporal dynamics of urban sprawl and growth pattern using geospatial technologies and landscape metrics in Bahir Dar, Northwest Ethiopia

Abstract

This study tried to assess and monitor the spatiotemporal dynamics of urban sprawl and its growth pattern in Bahir Dar, Northwest Ethiopia for the last three and half decades (1984 – 2019). Supervised maximum likelihood technique has been used to map the land use land cover of Bahir Dar from 1984 to 2019 using Landsat TM and OLI datasets. Post classification comparison, spatial landscape metrics, and Shannon’s entropy index were used to detect changes in land use land cover, investigate the complex spatiotemporal dynamics and degree of urban sprawl. Findings of this study indicated that in the study periods, the built-up area increased at the expanse of cropland and forest. The values of Shannon’s entropy index were scaled from 0.45 to 0.74 between 1984 and 2019. Spatial metrics analysis was also computed using CA (261–2566), NP (371 – 3576), PD (1.74 – 9.72), LPI (12−52), ED (7.09 – 46.77) and FRAC-AM (1.12 – 1.25); indicated the existence of sprawl with high dispersion and heterogeneity which gradually expanded from central business district (CBD) to the periphery. The rapid urban expansion which in turn results in urban sprawl has various socio-economic and environmental consequences if sustainable urban planning and management policies are not properly prepared and utilized. The study can enable to devise proper policies and strategies for effective utilization of resources and allocation of infrastructure by controlling improper enforcement of land use.