Using allometric models to estimate aboveground biomass and predict carbon stocks of mango (Mangifera indica L.) parklands in the Sudanian zone of Burkina Faso

Abstract

Tree growth is an important means of capturing and storing atmospheric carbon and is thus a key to mitigating the effects of climate change. Over recent decades, mango (Mangifera indica L.) parklands have expanded in Burkina Faso, due to the species’ fast growth and its compatibility with local agricultural crops. However, the contribution of mango parklands to reducing atmospheric CO2 remains unknown, due to the lack of local tools for aboveground biomass (AGB) estimation. The aim of this study was to develop accurate allometric equations for estimating the AGB and carbon (C) stocks of mango parklands. A field survey was carried out to select mango parklands according to their age. These parklands were then classified into six groups age (0≦y<5, 5≦y<10, 10≦y<15, 15≦y<20, 20≦y<25, y≧25) and dendrometric measurements were taken within 72 plots of 2500m² each. Inventoried mango trees were grouped into 5 diameter at breast eight (DBH) classes and the number of trees sampled per DBH class was a function of the class homogeneity. Twenty-five (25) mango trees were destructively sampled to estimate tree AGB. The belowground biomass was calculated based on existing mango root-to-shoot ratio data. The C content in tree aboveground components was evaluated using the ash method. Power and linear models were tested and fitted to the total AGB. The validated equations showed a good fit and performance with high explained variance (R² = 95%). The power model was the best model with DBH alone being the best predictor. The obtained means (±Standard deviation) AGB, belowground and total biomass were 326.64±279.1; 84.93±72.58 and 411.56±351.75 kg tree−1 respectively. The C content of the leaves, branches and trunk were 53.79, 54.78 and 55.79% respectively, whereas the mean C stock for aboveground, belowground and total C were 179.90; 42.46 and 222.36 kg tree−1 respectively. For a density of 152.30 ± 36.83ind ha−1, the mean aboveground and belowground biomass was 62.67 t ha−1, giving a total C stock of 33.85 t C ha−1for the studied mango parklands.