INDIVIDUAL BIOMASS OF Bambusa oldhamii Munro AND Bambusa vulgaris Schrad. ex J.C. Wendl.

This paper aimed to quantify the total biomass of two species of bamboo: Bambusa oldhamii and B. vulgaris. The distribution of biomass compartments (stem, leaves, rhizomes and stems) was studied, its correlation with biometric measures analyzed, as well as testing the performance of different biomass equations (total and by compartments) in terms of such variables. A total of 40 individuals (stems and its compartments) was collected in Bauru - SP, 20 of each species was sampled. Bamboo culms diameter range was 5-10 cm. The plants were measured, felled and weighed. A correlation analysis was carried out and, after meeting the assumptions, linear regression was applied. Individual dried biomass totals ranged from 7 to 33 kilograms, with little variation between the two species. The largest fraction of biomass occurred in the culm (75 and 68%, respectively for B. oldhamii and B. vulgaris). The easy-to-measure biometric variables (diameter at breast height - dbh, height, collar diameter) were significantly correlated to one another and strongly associated with total and culm biomasses. The best fit model for B. oldhamii is the one that expresses the direct relationship of dry biomass as a function of dbh only, whereas for B. vulgaris is the one with the expression of the direct relationship of dry biomass with the combined variable dbh 2 h. Attempts to fit models by compartment did not provide satisfactory results due to the low correlation between the variables studied. It was concluded that it is possible to express the total biomass of both species by regression equations, but not their separate compartments, except for the culm compartment.

bamboo; mathematical equations; modeling