Abstract

AQUINO-RAMIREZ, Martín et al. Aboveground biomass allocation in three tropical tree species. Agrociencia [online]. 2015, vol.49, n.3, pp.299-314. ISSN 2521-9766.

Knowledge of forest carbon stores is fundamental to generating inventories that approximate real C stores. For these inventories, it necessary to have estimations of tree biomass. Allometric equations are tools for estimating biomass and its distribution in forest ecosystems. The objective of this study was to develop equations to estimate total above-ground biomass and the biomass of structural components of trees in the physiographic region of the Sierra Madre del Sur, in the municipality of Pluma Hidalgo, Oaxaca, Mexico. The species selected for their relative abundance were Cupania dentata DC., Alchornea latifolia Sw. and Inga punctata Willd. These species were grouped using an additionality test; a regression model was used resulting in two groups. In the models fit for estimation of total above-ground biomass, the predicting variables were diameter at breast height and total tree height. Indicator variables were also included to define the effect of the group within the model. Models were fit by linear and non-linear regression, which resulted in high values of the adjusted coefficient of determination (R²_Adj > 0.98). This showed differences in the quantity of total aerial biomass between groups, a situation that was attributed to the specific density of the wood and to tree morphology. Biomass in the structural components of the tree (stump, stem, bark, branches and leaves) was estimated with a system of equations based on partition factors using SUR (Seemingly Unrelated Regressions) to fit the regression parameters. In the three species, the greatest accumulation of biomass was concentrated mainly in the branches, followed by the stem, bark, stump and leaves.

Keywords : Tropical trees; indicator variable; allometric equations; Cupania dentata; Alchornea latifolia; Inga punctata.