Abstract:
Woodlands in the Sudanian zone are under different management regimes, including total protection and controlled use mainly for feeding livestock and collecting fuelwood. This study conducted in Sudanian woodlands of Benin, around the Biosphere Reserve of Pendjari (BRP) aimed to: (i) determine the effect of selective stem thinning and branch pruning on the production of standing biomass of the woodlands; and (ii) assess the effectiveness of Sudanian woodlands to meet the fuelwood demand of the local population. Three vegetation units of about 80 m × 80 m each were identified, relatively uniform floristically and structurally, and representing three woodland development stages in Sudanian woodlands. Three random blocks (replications) of 20 m × 20 m each were demarcated within each vegetation unit. Each block was then divided into four treatment plots of 10 m × 10 m each. Treatments were randomly allocated and consisted of i) no thinning (T1), ii) 30% thinning (T2), iii) 60% thinning (T3), and iv) 100% thinning (T4). Standard branch pruning was applied to all remaining stems. The species name, diameter and/or height of the remaining stems ≥ 1 m height were recorded twice during the year period between 2015 and 2016. A semi-structured questionnaire was randomly applied to 150 households to record detailed information on the tree species as well as the quantity of fuelwood used or sold each day. Thinning and pruning had a positive effect on biomass production. The best biomass production (0.88 t/ha/year or 15,028.5 t/year for an area of 16,938.7 ha) was obtained with 60% thinning and pruning. Whatever the treatment, the biomass production did not meet the demand for fuelwood of the local population around the BRP. A deficit between 69.5% (T1) and 64.6% (T3) was observed. The mean per capita fuelwood needs of the households was 1.3 kg/day, and decreased with increasing household size. Extending the experimentation over a longer period (at least ten years), and establishing and using the allometric equations of recorded tree species will improve the estimation of the biomass production of these woodlands.
