Untrimmed fresh biomass
Untrimmed biomass is measured indirectly as non-destructive. The small untrimmed branches with less than 10cm basal diameter were processed differently from the large branches and the trunk. For the small branches, only basal diameter was measured. The biomass of these small untrimmed branches with their accompanying twigs and leaves was estimated from the relationship between their basal diameter and the regression developed from the trimmed branches (Vann et al ., 1998; Picard et al ., 2012).
The biomass of the trunk and the large branches was estimated from measurements of volumes (Vi in cm3) and mean wood density (ῥ in g cm−3). The large branches and trunk were divided virtually into sections that are then materialized by marking the tree. The volume Vi of each section i was obtained by measuring its diameter and its length. Diameter measurements were carried out in sections of about two meters in length along the length of the trunk. For larger branches greater than 10 cm in basal diameter, diameter measurements were conducted in sections of 50 cm in length using tree caliper.
The volume (V aliquot fresh wood) of the wood aliquot taken from the trimmed compartments was measured by measuring the volume of water displaced when the sample is immersed in water using a graduated tube of suitable dimensions for the sample (Picard et al ., 2012). The dry biomass of the tree was obtained by the sum of the trimmed dry biomass and the untrimmed dry biomass:
B dry = B trimmed dry + B untrimmed dry
2.3 Data analysis