Landscape Transformation, Forest Fragmentation, and Structural Connectivity Along an Edge-to-Core Gradient in a Protected Miombo Woodland of the DR Congo

Understanding how land-use change affects habitat fragmentation and connectivity is essential for assessing landscape degradation and conservation effectiveness in tropical protected areas. This study investigated long-term landscape dynamics, forest fragmentation, and structural connectivity in the Bena Mulumbu Hunting Domain, a Category VI protected area located in the miombo woodland region of southeastern Democratic Republic of the Congo. Landsat imagery acquired in 1995, 2005, 2015, and 2025 was classified using the Random Forest algorithm to quantify land-cover changes over a 30-year period. Landscape composition was assessed using land-cover proportions (PLAND), Shannon diversity metrics, and transition analyses, while fragmentation and structural connectivity of miombo woodland were evaluated along an edge-to-core gradient (0–2 km, 2–4 km, 4–6 km, and >6 km) using landscape metrics. Results showed that savanna remained the dominant land-cover type throughout the study period. However, the landscape underwent progressive reorganization characterized by recurrent transitions among miombo woodland, savanna, and agricultural land, leading to increased spatial heterogeneity. Fragmentation analyses revealed significant differences among spatial gradients for the number of forest patches (p = 0.022) and total core area (p < 0.001), indicating a gradual reduction of interior forest habitat. Despite increasing fragmentation, structural connectivity remained relatively high across the protected area. The CONNECT index increased significantly from the edge toward the core zone (p < 0.001), highlighting better-connected forest networks in interior sectors. These findings suggest that the Bena Mulumbu Hunting Domain is experiencing an intermediate stage of landscape transformation, where forest fragmentation is evident but has not yet resulted in widespread connectivity loss. Maintaining existing forest cores and connectivity corridors should therefore be prioritized to prevent further degradation of ecological integrity.