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Báo cáo khoa học: "Comparison of biomass component equations for four species of northern coniferous tree seedling"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Comparison of biomass component equations for four species of northern coniferous tree seedlings. | Ann. For. Sci. 56 1999 193-199 Inra Elsevier Paris 193 Original article Comparison of biomass component equations for four species of northern coniferous tree seedlings Robert G. Wagner Michael T. Ter-Mikaelian Ontario Forest Research Institute Sault Ste. Marie Ontario P6A 2E5 Canada Received 10 November 1997 accepted 10 November 1998 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 R2 for 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 R2 for total aboveground branch and foliage biomass equations by 2.5 . Adding tree height improved the adjusted R2 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. biomass prediction jack pine Pinus banksiana red pine Pinus resinosa I white pine Pinus strobus I black spruce Picea mariana Resume - Comparaison d equations des composantes de la biomasse pour des jeunes plants de quatre espèces de coniferes canadiens. Nous avons développé et compare des equations de prediction des composantes de la biomasse feuillage branches tronc racines total aérien et total arbre pour des jeunes plants de quatre espèces de coniferes pin gris Pinus banksiana Lamb. pin .