Dynamics and change in forest cover in selected forest reserves in Osun State, Nigeria

Abstract

We assessed forest depletion and land cover changes in Ago-Owu, Ife, Oni, and forest reserves (FR). Landsat 5 (TM), Landsat 7, (ETM) + Landsat 8 OLI for 1994 – 2024. The supervised classification with the maximum likelihood algorithm was applied for image classification to generate land use and land cover categories. LULC change detection between 1994 - 2024 was conducted to analyse the change and patterns. Significant transformation was observed in all the forest reserves. In Ago-Owu (FR), dense (DF) forest decreased from 12, 033.50 ha in 1994 to 3,910.76 ha in 2024. Agricultural land (AL) area increased from 1585.1 ha in 2004 to 4349.89 ha in 2024 while bare land (BL) increased from 824.92 ha in 1994 to 4890 ha in 2024, and builtup (BU) area increased from 102 26 ha to 2050.90 over the thirty-year period. In Ife, native forest reserve, DF plummeted from 9717.81 ha in 1994 to 2550.93 in 2024. AL land and BU area increased from 138.9 ha to 2620.54 and from 15.20 ha to 3857.90 ha, respectively, over the same period. In Oni forest reserve, DS retracted from 4,121.00 ha to 2,229.93 ha while the share of agricultural land of the forest increased to 873.53 ha, 476.21 ha of bare land, and 501.75 ha of built-up area. This research provides key insights into the evolution of landscape dynamics of the forest reserve and provides valuable information for practices of sustainable land management.