Assessment of Land Use and Land Cover Dynamics in the Cavally River Watershed, Western Côte d’Ivoire

Abstract

Rapid population growth and expanding mining activities, especially in Africa and Côte d’Ivoire, are driving deforestation and land-use changes, threatening biodiversity and ecosystem services. In areas like Zouan-Hounien, intensive gold mining has replaced agriculture, leading to significant environmental degradation and vegetation loss. This study aims to evaluate the spatiotemporal dynamics of land use and land cover within a sub-watershed of the Cavally River. To achieve this objective, four Landsat satellite images were acquired from the U.S. Geological Survey website. The dataset includes Landsat Thematic Mapper (TM5) imagery from 1985, Landsat Enhanced Thematic Mapper Plus (ETM+) imagery from 2000, and Landsat 8–9 Operational Land Imager (OLI) imagery from 2015 and 2025. The methodological approach relied on the application of remote sensing techniques. Image preprocessing and processing workflows enabled the production of land-cover maps for each reference year. Five major land-cover classes were identified from the Landsat images: dense vegetation, degraded vegetation, agricultural areas, settlements and bare soils, and water bodies. Area estimates derived from the classification results show a substantial decline in dense vegetation, decreasing from 226.49 km² (48.74%) in 1985 to 40.96 km² (8.81%) in 2025. This pronounced loss of forest cover is largely attributable to mining activities and rapid population growth, which have intensified anthropogenic pressures on the environment. Concurrently, agricultural land expanded considerably, from 39.79 km² (8.56%) in 1985 to 116.19 km² (25%) of the total area of the sub-watershed in 2025, reflecting increasing demand for arable land.