Abstract: Based on the fractal theory of forest growth, stepwise regression was employed to pursue a convenient and efficient method of measuring the threedimensional green biomass (TGB) of urban forests in small area. A total of thirteen simulation equations of TGB of urban forests in Shen-yang City were derived, with the factors affecting the TGB analyzed. The results showed that the-coefficien-ts of determination (R²) of the 13 simulation equations ranged from 0.612 to 0.842. No evident pattern was shown in residual analysis, and the precisions were all higher than 87% (α=0.05) and 83% (α=0.01). The most convenient simulation equation was lnY=7.468+0.926 lnx₁, where Y was the simulated TGB and x₁ was basal area at breast height per hectare (SDB). The correlations between the standard regression coefficients of the simulation equations and 16 tree characteristics suggested that SDB was the main factor affecting the TGB of urban forests in Shenyang.

Key words: evergreen woody plant, plant functional trait, frost-resistance, mechanical damage-resistance, plant selection, evaluation index system.