Diachronic Analysis of Land-Use and Forest-Cover Changes in the Irobo Classified Forest (Sikensi, Côte d’Ivoire)
Abstract
The decline in forest cover is a major conservation challenge in Côte d’Ivoire, where agricultural expansion exerts considerable pressure on forest ecosystems. The objective of this study is to analyze spatiotemporal changes in land use and forest cover in the Irobo Classified Forest between 1988 and 2026 and to assess a trend-based scenario of 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. Forest cover decreased from 19,105.81 ha (46.67%) in 1988 to 8,278.17 ha (20.22%) in 2026, representing a loss of 10,827.64 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 classified forest area. Spatial analysis indicates that the remaining forest areas became more scattered and less spatially continuous between 1988 and 2026. Under the trend-based scenario, forest area could decline to approximately 4,881.19 ha by 2050, representing 11.92% of the classified forest area. These findings demonstrate the usefulness of combining remote sensing, GIS, and field observations to quantify long-term land-use changes and identify forest areas potentially exposed to future conversion. They provide a spatial basis for forest monitoring, conservation, and restoration planning in the Irobo Classified Forest.
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References
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