CoEB seminar session by Angelina Serwaa

Assisted Natural Regeneration (ANR) has emerged as a low-cost strategy for restoring degraded tropical forests, yet its long-term effects on post-fire montane forest recovery remain poorly understood. We evaluated forest recovery nearly two decades after wildfire in Nyungwe National Park, Rwanda, comparing ANR plots, Unassisted Natural Regeneration (UNR) plots, and nearby unburnt forest as a reference. Permanent plots established in 2007 were resampled in 2025, with ANR plots receiving repeated bracken fern (Pteridium aquilinum) removal. We quantified forest structure, species richness, diversity, and community composition using univariate analyses, ordination, generalized linear models, and variance partitioning. Forest structure, species richness, and diversity were consistently higher in unburnt forest and ANR than in UNR across all metrics. Community composition showed contrasting responses between vegetation layers: overstory composition in ANR remained distinct from unburnt forest, with greater dominance of early successional species, while understory composition in ANR more closely resembled unburnt forest and retained a higher proportion of late successional species. UNR remained dominated by early successional species in both layers, consistent with arrested succession under persistent bracken cover. Variance partitioning indicated that spatial structure was the primary driver of overstory compositional variation, while forest treatment was the strongest independent driver of understory composition, suggesting ANR's effects on compositional recovery are more detectable in the understory at this successional stage. Our findings indicate that ANR effectively promotes structural and diversity recovery in post-fire Afromontane Forest, with early signs of understory compositional convergence toward unburnt forest, though full recovery across both vegetation layers will likely require several more decades.