Impact of Faidherbia albida (Delile) A. Chev. density on soil organic carbon, soil nitrogen, crop yields, and rural livelihoods in Northern Cameroons Agroforestry parklands

Trees in parklands can interact with crops positively or negatively based on species, environment, and management. Faidherbia albida is an agroforestry tree that can improves soil fertility and provides ecosystem services beneficial to smallholder farmers. This study examined the effects of F. albida tree density and pruning on soil organic carbon (SOC), total nitrogen (STN), crop yields, and rural livelihoods in North Cameroon. Parklands were categorized by tree density: low (10 - 30 trees/ha), moderate (40 - 60), and high (≥ 80). Topsoils (0 - 20 cm) were sampled, and agronomic trials were conducted over two years. SOC and STN levels were higher under F. albida canopies, especially in high-density, pruned parklands. Sorghum yields were highest (2.269 ± 0.590 t/ha) in pruned, moderate-density plots, while cowpea yields reached 1.854 ± 0.282 t/ha in unpruned plots. Pruning enhanced sorghum yield, whereas cowpea performed better in unpruned conditions. Beyond crops, parklands supported rural incomes through wood fuel, fodder, and timber, contributing 58.7 ± 19.9% of household income in Mambang and 56.1 ± 18.5% in Kodek. The results highlight F. albida’s potential to improve soil quality, increase crop productivity, and support livelihoods, reinforcing its value as a climate-resilient agroforestry option for Northern Cameroon.