عنوان مقاله [English]
Today, poplar plantation is considered an important forestry practice for preservation of carbon pools and a major source for bioenergy and cellulose. Providing different allometric equations, this research presents a model that may improve the biomass estimation of P. deltoides in Talookola Nursery in Sari. A number of 25 cuttings with 25 cm length were planted in 2011 within 1*1 m plots with identical site condition in three-replication experiment. Saplings numbered 4, 12 and 18 were randomly selected in three diameter classes (0-1, 1.1-2, 2.1-3 cm), respectively. The weight/wet weight ratios were measured after roots and stems were oven-dried at 85 ºC for 48 hours. Collar diameter and sapling height were chosen as variables for modeling allometric equations. The results showed that the logarithmic model related to above-ground biomass including collar diameter (D) and logarithmic models including product of diameter square and height (DBH2 × H) associated with below- and total ground biomass had the highest accuracy with the best goodness of fit data. Moreover, multivariate empirical models which did not have multicollinearity (VIF < 10) were presented, as such. However, they were not well fitted compared to aforementioned optimal models. The presented models can be considered as the applicable tools for estimation of annual biomass production and carbon sequestration of the studied species.