Monitoring Urban Sprawl in Greater Karu Urban Area (Gkua), Nasarawa State, Nigeria.

Greater Karu Urban Area (GKUA) has been experiencing a large influx of population due to unprecedented rate of urbanization from all parts of Nigeria and elsewhere. This has led to rapid expansion and sprawl of the young settlements resulting in land use and land cover changes, transforming the entire landscape from rural to urban. The techniques of using Remote Sensing and Geographical Information System (GIS) to monitor and map urban sprawl are described in this paper. The built up areas were obtained from Land Sats and Nigerian Sat1 imageries of four different periods covering a 35 year period. Further analysis of the imageries revealed significant dynamic changes in the growth of the settlements in GKUA over time. The study shows a discontinuous spread of settlements leap-frogging into each other along the Keffi-Abuja High way, fast spreading into the hinterland and converting viable agricultural lands into urban development, an evidence of rapid sprawl. The study also shows more intense physical development along the high way and settlements closer to the Federal capital Territory like Mararaba, Karu, Nyanya and Masaka than settlements farther away. This study has provided quantitative and qualitative data for effective planning, policy and decision making for a more sustainable development of settlements in GKUA. Key Words: Urban Sprawl, GIS, Built-up, Monitor, Patterns of spraw