Deforestation is one of the major environmental problems in Nigeria, drastically reducing the amounts of green cover in the country and eroding the economic, environmental and social values of the plant communities. It is pertinent to understand the extent and distribution of this degradation, including the dynamics in the other related land uses such croplands. Remote sensing data, tools and methods are effective in determining and documenting these land dynamics. Two satellite imagery of 1986 and 1999 were analysed to determine land changes that occurred between these two periods in an area covering about 500,000 hectares in the rainforest area of southwest Nigeria. Thus, the method applied was image processing using Erdas-imagine software. The process involves pre-processing of the imagery, classification and accuracy assessment. The result shows that 17, 472 hectares of forest were removed during the period under review. The extent of surface water bodies, settlements and bare ground increased by 1,131, 9,073 and 15,565, respectively. Agricultural land decreased by 8,296 hectares which could be related to the urban expansion and other infrastructural development in the area. This analysis was constrained by time, resources and the techniques. However, it provided some idea about change in the plant cover in the area from 1986 to 1999. This work could be scaled to national scope.

Keywords : Land cover change, satellite imagery, image processing, deforestation, tropical rainforest, southwest, Nigeria