Diachronic Analysis of the Irobo Classified Forest (Sikensi, Ivory Coast)
Abstract
The decline in forest cover is a major conservation challenge in Côte d’Ivoire, where the expansion of agricultural activities exerts considerable pressure on forest ecosystems. This study analyzes the spatiotemporal dynamics of land use in the Irobo Classified Forest between 1988 and 2026 and proposes a trend-based scenario for forest cover change by 2050. The study used Landsat 4 TM and Landsat 8 OLI/TIRS satellite imagery processed in Google Earth Engine, supplemented by GIS data and field observations. Supervised classification using the Classification and Regression Trees (CART) algorithm was used to distinguish four land-use classes : water bodies, forest, cropland/fallow land, and settlements/bare land. The results reveal a substantial decline in forest cover, which decreased from 19105.81 ha (46.67%) in 1988 to 8278.17 ha (20.22%) in 2026, representing a loss of 10827.64 ha, or 56.67% of the initial forest cover. The average annual forest loss was estimated at 284.94 ha/year, corresponding to an annual deforestation rate of 2.20%. Meanwhile, cropland and fallow land increased from 50.69% to 79.10% of the total area of the classified forest. Spatial analysis also reveals fragmentation and reduced continuity of the remaining forest cover. According to the trend-based scenario, forest area could decline to approximately 4881.19 ha by 2050, representing 11.92% of the total area of the classified forest. These results highlight the importance of strengthening forest monitoring, conserving remaining forest areas, and implementing restoration measures to promote the sustainable management of the Irobo Classified Forest.
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References
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