ALLOMETRIC RELATIONSHIPS FOR PREDICTING THE BIOMASS IN Dalbergia sissoo ROXB. PLANTATION IN PUNJAB, PAKISTAN

Allometric relationships for estimating the above and below ground biomass and its allocation at four different ages (viz-a-viz 6,11,16 and 20 years) of Dalbergia sissoo were investigated in monoculture irrigated plantation of Punjab Pakistan. Destructive sampling (including stump removal) of true representative trees was carried out in spring, summer and autumn seasons of the year 2010, 2011 and 2012. Results indicate that a linear relationship exists in general between age, diameter, height and volume of the tree. The total biomass of D.sissoo estimated at four age brackets showed a linear relationship, where it was minimum (144.83 kg tree^-1) at the age of 6 years, while the maximum weight (456.37 kg tree^-1) was observed at the age of 20 years. Maximum above ground biomass contribution was from stem (38%) followed by branches (32%), twigs (9%) and leaves (5%) respectively whereas, underground portion of the tree i.e root contributed 16% of the total biomass. The study also indicated that, right now the plantation compartments having trees of age 6, 11, 16 and 20 years are not equal in numbers/areas due to which sustained production is not available. The present study might be the first for D.sissoo in Pakistan as no significant literature is available for the estimation of biomass expansion or allocation in different tree components of the species. So the results of the study are helpful in determining the amount of carbon credits earned by plantations on area basis, which are requisite under the Kyoto Protocol and REDD policy.