Early-stage leaf litter decomposition of miombo tree species is more strongly driven by leaf litter chemistry than by charcoal-induced disturbance in forests around Lubumbashi, DR Congo

Litter decomposition is a key ecosystem process because it regulates carbon storage and nutrient availability, yet it remains poorly documented in miombo woodlands. This study assessed how leaf litter quality affects decomposition rates and whether these effects are modified by charcoal-induced forest disturbance. Leaf litter from 10 major miombo tree species with contrasting litter quality was incubated using the litterbag method over four periods (1, 3, 6, and 12 months) in less disturbed forests (LDF) and charcoal-disturbed forests (CF). Overall, litter mass loss was significantly higher in LDF than in CF at each incubation duration. However, the difference was modest (cumulative mass loss after 12 months: 31.1% in LDF vs 29.1% in CF) and varied among tree species. Over the 12-month period, mass-loss patterns differed strongly among the 10 tree species, with final average mass loss ranging from 19.9% ( Brachystegia boehmii ) to 40.2% ( Julbernardia globiflora ). Species effects on mass loss were associated with leaf litter chemistry. Calcium concentrations, together with other base cations, were positively associated with decomposition during the first 6 months, whereas high Mn concentrations, high C/N ratios, and low N concentrations were negatively associated with mass loss over 12 months. These findings highlight the importance of species-specific litter traits and disturbance-induced changes in regulating nutrient cycling. They also suggest that continued charcoal-driven degradation may alter ecosystem functioning and resilience in miombo woodlands.