Comparison of biomass component equations for four species of northern coniferous tree seedlings

Abstract

We compare equations predicting the biomass components (foliage, branches, stem, roots, total aboveground and total tree) for seedlings of four coniferous tree species: jack pine (Pinus banksiana Lamb.), red pine (Pinus resinosa Ait.), eastern white pine (Pinus strobus L.) and black spruce (Picea mariana (Mill.) B.S.P.) grown under controlled experimental conditions for 3 years. Coefficients of determination (Rfor the component equations exceeded 0.9 for jack and red pine, and ranged from 0.7 to 0.9 for white pine and black spruce. Basal diameter was the most important variable in all equations. Adding crown width improved the adjusted R for total, aboveground, branch and foliage biomass equations by 2.5 %. Adding tree height improved the adjusted R for stem biomass equations by 6.2 %. Root biomass equations were not improved by including height or crown width. Using statistical comparisons of the full model (i.e. separate equations for each species) with three alternative reduced models that pooled various combinations of species, we determined that none of the biomass component equations could be combined among the four conifer species. (© Inra/Elsevier, Paris.)