Quantifying Accessibility-Driven Forest Degradation in a Mining Frontier of Southeastern DR Congo Using Landsat Time Series and Landscape Metrics

The miombo woodlands of southeastern Democratic Republic of the Congo (DR Congo) are increasingly threatened by mining expansion and associated land-use changes. Unlike previous studies focusing separately on mining impacts or land-cover change, this study explicitly quantified the combined influence of mining roads and settlements on forest degradation gradients in an emerging mining frontier. The study was conducted in the Mutshatsha Territory, a rapidly transforming landscape within the Katangese Copperbelt. Land-cover dynamics between 1998 and 2023 were reconstructed from six Landsat image series using Random Forest classification implemented in Google Earth Engine. Landscape transformation was assessed through landscape ecology metrics, while accessibility effects were quantified using spatial gradients around a mining exploration road and four villages representing contrasting accessibility contexts. Forest cover declined from 39.9% in 1998 to 12.5% in 2023, corresponding to an annual deforestation rate of 2.75%, substantially exceeding the national average for DR Congo. Simultaneously, agricultural land, built-up areas, and open vegetation expanded, while landscape disturbance increased and forest patch cromplexity decreased. Forest cover consistently increased with distance from both villages and the mining road, demonstrating strong accessibility gradients. Distance from villages explained up to 80% of the variation in forest cover, whereas road-distance gradients accounted for 71–94% of the observed variation. Forest loss along the mining road extended up to approximately 5 km from the corridor and intensified over time. Villages located along the RN39 transportation corridor exhibited substantially greater forest depletion than the more isolated village of Mpwita. These findings demonstrate that mining roads and settlements operate synergistically to structure forest degradation patterns through accessibility-driven processes. Integrating accessibility considerations into land-use planning and conservation strategies is therefore essential for mitigating forest degradation in rapidly expanding mining frontiers.