Comparative Effect of Biochars on the Growth of Afzelia africana and Pterocarpus erinaceus in Nursery Conditions in Faranah, Guinea

Aims: This study aims to assess the effects of various biochar types on the germination, growth, and biomass of two native West African forest species, Afzelia africana and Pterocarpus erinaceus, under controlled nursery conditions, and to identify suitable biochar treatments for enhancing reforestation practices in Guinea. The study also seeks to provide actionable insights into improving soil resilience and forest growth strategies.

Study Design: Experimental design with five treatment groups.

Place and Duration of Study: Nursery trials conducted at Faranah, Guinea, over a six-month period.

Methodology: Five biochar treatments were applied: straw biochar (BP), peanut shell biochar (BCA), corn stalk biochar (BCM), household waste biochar (BDM), and a control with no biochar (D0). Key parameters measured included germination rate, leaf area, leaflet and leaf counts, as well as fresh and dry biomass for each species. Statistical analyses included normality tests, ANOVA, and Tukey’s post-hoc tests, ensuring robust evaluation of treatment effects on measured parameters.

Results: Significant variations were observed across treatments for several growth parameters. Afzelia africana responded favorably to BCA and BDM treatments, exhibiting increased leaf area, number of leaves, number of leaflets, and higher fresh and dry biomass (p < 0.05). Conversely, Pterocarpus erinaceus showed improved germination rate, germination energy, germination speed, and leaf area with the BCM treatment. The findings highlight strong correlations between germination and biomass parameters for Afzelia africana, underlining its resilience to substrate variation and the importance of biochar choice.

Conclusion: Tailoring biochar application to species-specific needs can enhance nursery growth conditions for reforestation purposes. BCA and BDM treatments are most beneficial for Afzelia africana, while BCM is optimal for Pterocarpus erinaceus. These results underline the practical potential of biochar in advancing reforestation initiatives and improving soil management strategies in Guinea’s nursery settings.