keywords: Change detection, geographic information system, remote sensing, urbanisation, Warri
Urbanisation, though a welcome development in any society, is not bereft of certain negative effects especially when it occurs in an unorganised fashion resulting in the development of slums. The need to ensure adequate planning through inventory and monitoring using advanced technology becomes necessary. This scenario is the characteristic of Warri and its environs. This study was designed therefore to monitor the extent and pattern of growth of Warri and its environs, between 1987 and 2014, using Geographic Information System and Remote Sensing. Landsat thematic mapper and Enhanced thematic mapper satellite imagery for 1987, 2007 and 2014 were analysed for change detection. ArcGIS and Erdas Imagine were used to prepare the maps. A questionnaire survey involving one hundred and twenty respondents was carried out. The classification scheme was in the following manner: Built up area, vegetation, water body and bare land. An increase of 4% in 2007 and 27% in 2014, in the built up area were recorded. Vegetation land use increased by 9% by 2007, and decreased by 28% in 2014. The bare land and water body land uses were seen to fluctuate marginally through the period under study. The commercial land use was perceived to be the most dominant as asserted by 43% of the sample population. Congested road was perceived to be a major negative effect on the people, as asserted by 38% of the sampled population. The results imply an increasing rate of urbanisation which can be sustainably managed proactively adoption of regular periodical monitoring and collection of data to aid planning. In addition, environment friendly strategies and interventions such as reforestation/ afforestation, planting of green area parks should be adopted and implemented.