BIOMASS AND CARBON ESTIMATION IN AN Abies religiosa FOREST

Abstract

Two equations were generated to determine biomass and carbon in Abies religiosa (H.B.K.) Schl. et Cham. These equations were of the form Y = b X^k, where Y is the content of biomass or carbon, and X the diameter at the breast height (DBH). In order to estimate the values b and k, date from 26 trees of an area under forest management were used, with basal a diameter between 6.5 and 79 cm at the stand called "El Innominado" at San Felipe Hidalgo, in Nanacamilpa County, Tlaxcala, México. The biomass of each component of every tree was determined (logs, branches and foliage). Ten random subsamples of log, ten of branches and six of foliage were analyzed to determine carbon content. The carbon concentration in log was 46.6 %, in branches was 46 % and 46.1 % in the foliage. The carbon concentration average by tree was 46.5 %. The greater percentage of biomass (84.5 %) was found in the log including the stump, whereas in the branches in and the foliage it was 6.9 and 8.6 %, respectively. The adjustment of parameters b and k of the proposed model were obtained with the biomass and the basal diameter of the 26 trees (B = 0.0713 DN^2.5104). The variables of the predictive model of accumulated carbon by tree (CAA) based on the Dbh were determined by an identical procedure, and the result was CAA = 0.0332 DN^2.5104. The parameters for both equations had a coefficient of determination (R²) of 0.99.