Allometric model of wood biomass and carbon for gliricidia (gliricidia sepium (JACQ.) kunth ex walp.) at bioenergy plantation in Indonesia

The paradigm of multipurpose forest management in gliricidia plantation can be developed to produce woody biomass and carbon stock. Production estimation of gliricidia plants in producing woody biomass and carbon stocks needs to be estimated through allometric models. The research objective is determining the best allometric equations of wood biomass and carbon stocks with predictors of stem diameter. The materials used in the study were the gliricidia stand with age 1-5 years at Forest Management Unit Semarang. The method used in measuring and estimating forest carbon stocks refers to Indonesian National Standard (SNI) No 7724: 2011 and the SNI No 7725: 2011. The results showed that the biomass of gliricidia plants was distributed in stems (10.75 ), branches (86.30 ), and leaves (2.93 ). Furthermore, the average carbon content in stems was 57.40 , in branches - 56.30 , and in leaves - 52.90 of the dry weight. R2adj of allometric models were 0.780 (linear); 0.730 (exponential); 0.532 (logarithmic); 0.799 (polynomial); and 0.959 (power). While the RMSE values were 38.89 , 1.20 , 56.66 , 37.16 , and 0.48 , respectively. The allometric model validation showed that power model is the best allometric model for wood biomass and total carbon content. Thus, it can be considered to estimate wood biomass and total carbon with predictors of stem diameter. Further research by adding other predictors is needed to make the result of allometric models more accurate. © 2020 Lesotekhnicheski Universitet (University of Forestry). All rights reserved.