Application of Remote Sensing and GIS in Examining The Rate of Urban Expansion in Oyi Local Government Area of Anambra State - Nigeria from 2005-2023

Urban expansion constitutes one of the key agents of land-use change with the impact felt at local, regional and global levels. Such impact includes spatial growth on agricultural lands. This study assessed the rate of urban expansion into agricultural lands in Oyi Local Government Area of Anambra state, Nigeria, using remote sensing and geographic information techniques. Two imageries of Landsat 7 images of 2005 and 2015 and that of Landsat 8 of 2022 Enhance Thematic Mapper (ETM⁺) on Path 189 and Row 056 were acquired during the same season to ensure uniform reflectance of geographic features in other to reduce error during image analysis. Layer stacking of the different bands of the images of same spatial location was done using ArcGIS 10.4 software, the images were georeferenced using projected coordinate system (PCS), Universal Transverse Mercator (UTM) coordinate system, Datum World Geodetic survey (WGS) 1984; Northern hemisphere, Zone 32.  The findings revealed that from the image classification analysis of 2005, bare surface covers 17.52km², farm land covers 35.23km², forest covers 41.56km² and settlement covers 27.05km² of 121.381km² of the entire study area. For the 2015 bare surface covered 15.73km², farm land covers 19.79km², forest covers 32.25km² and settlement covers 28.48km² of 121.381km² of the study area and for the image classification analysis of 2022, bare surface covers 20.96km², farm land covered 18.14km², forest covers 38.69km² and settlement covers 43.57km² of 121.381km² of the study area. The comparison of these results shows that agricultural land in the study area was lost to urban expansion. From the foregoing, it is recommended that urban spreading to agricultural land should be controlled as this will have serious repercussions on food security.