2.2 Biomass Data collection
The studied forest was stratified into three forest strata based on the altitudinal variation. Strata one was found at an altitudinal range of between 1500-1800m while strata two and three were located between the altitudinal range of 1801-2000m and 2001-2300m respectively. Following the methodologies recommended in Picard et al ., (2012), area and species-specific allometric equations were formed involving a semi-destructive approach. Thirty individuals were systematically selected and sampled for measuring biomass along the three forest strata. In order to minimize the error of sampling and to obtain the representative tree and samples, diameter distributions were taken into account during tree selection. Accordingly, the trees were classified into five DBH classes and each class having six individuals per DBH class ranging from 10-20 cm, 20.1-30 cm, 30.1-40 cm, 40.1-50 cm and greater than 50 cm.Experienced persons climbing on live trees using ropes did the measurement of diameter at 2m interval in each section of a tree. Using data obtained by climbing live trees, aboveground biomass of trunk, branches and leaves were estimated. Generally, three random small branches with less than 10cm basal diameter per individual plant were destructed and trimmed. The measurements of fresh biomass (in kg) were divided into two parts: measuring trimmed fresh biomass and measuring untrimmed fresh biomass.