Assessing Anthropogenic Drivers and Biodiversity Indicators of Miombo Woodland Degradation Across Development Stages in the Lubumbashi Charcoal Production Basin, DR Congo

Miombo woodlands in the Lubumbashi Charcoal Production Basin (LCPB) provide critical ecosystem services and harbor biodiversity essential to both rural and urban populations. However, increasing energy demands intensify anthropogenic pressures, threatening their long-term sustainability. This study evaluates the principal anthropogenic drivers and biodiversity disturbance indicators across three developmental stages (7, 14, and 21 years) of miombo woodlands within the LCPB. Transect-based inventories assessed disturbance gradients, while plot-based surveys examined floristic composition and structure. Functional trait data were obtained from specialized online ecological databases. Results indicate that forest degradation within the LCPB is primarily driven by charcoal-related wood harvesting, fire events, and agricultural expansion, whereas exotic species invasion, debarking, and artisanal mining exert comparatively minor impacts. Disturbance patterns did not correlate significantly with proximity to villages, despite logging, fire, and agriculture being strongly interrelated. Analysis of the developmental stages revealed significant variations in biodiversity and dendrometric indicators. The highly degraded 7-year-old stage exhibited low floristic diversity, dominated by species such as Isoberlinia angolensis (abundance = 22), Julbernardia paniculata (18), and Brachystegia wangermeeana (6), and had poor structural metrics (90 individuals, 51 trees/ha, average DBH of 11.56 cm, average height of 4.47 m). The intermediate 14-year-old stage showed increased species diversity, notably B. wangermeeana (83), Brachystegia spiciformis (56), and Albizia adianthifolia (48), alongside improved structural values (456 individuals, 285 trees/ha, average DBH of 18.83 cm, average height of 6.31 m). The least degraded 21-year-old stage had the highest floristic diversity and structural values, with dominant species Marquesia macroura (88), Diplorhynchus condylocarpon (64), and Julbernardia globiflora (71), totaling 519 individuals, 323 trees/ha, average DBH of 24.20 cm, and average height of 9.64 m. Furthermore, ecosystem condition influenced functional traits, with disturbed areas favoring zoochorous dispersal and natural regeneration, but reducing wood density and nitrogen fixation. These findings underscore severe threats to LCPB woodlands and emphasize the importance of forest degradation stages in woodland development and resilience. Immediate action is recommended to regulate wood harvesting strictly, criminalize uncontrolled fires, monitor agriculture, and protect degraded areas to foster miombo woodland regeneration.