This paper established an integrated stand growth model of Mongolian oak(ISGM_oak) using the data from 61 permanent sample plots measured in 1997 and 2007.ISGM_ oak is a group of nonlinear simultaneous equations.The m...This paper established an integrated stand growth model of Mongolian oak(ISGM_oak) using the data from 61 permanent sample plots measured in 1997 and 2007.ISGM_ oak is a group of nonlinear simultaneous equations.The method of nonlinear error-in-variable simultaneous equations is used to estimate the parameters of ISGMoak with the statistical software Forstat 2.0,so the parameter estimation of the group of correlated equations in ISGMoak is unbiased and the equations are compatible.Model validation using bootstrap method showed that both the average relative error and square error are less than 15 percent.The ISGM_ oak model can be used to simulate the stand growth with different values of site index,stand density and to draw stand density management diagram for decision-making.展开更多
Models for quantifying the growth responses of black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) to precommercial thinning (PCT) treatments were developed. They accounted for the increased...Models for quantifying the growth responses of black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) to precommercial thinning (PCT) treatments were developed. They accounted for the increased rate of stand development arising from PCT treatments through temporal adjustments to the species and site specific mean dominant height-age functions. Analytically, they utilized a relative height growth modifier consistent with observed density-dependent height repression effects. A phenotypic juvenile age-mature age correlation function was used to account for the intrinsic temporal decline in the magnitude of the PCT effect throughout the rotation. The resultant stand development patterns were in accord with theoretical and empirical expectations when the response models were integrated into algorithmic variants of structural stand density management models.展开更多
Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.)...Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) plantations. The models accounted for the increased rate of stand development arising from the planting of genetically-improved stock through temporal adjustments to the species-specific site-based mean dominant height-age functions. The models utilized a relative height growth modifier based on known estimates of genetic gain. The models also incorporated a phenotypic juvenile age-mature age correlation function in order to account for the intrinsic temporal decline in the magnitude of genetic worth effects throughout the rotation. Integrating the functions into algorithmic variants of structural stand density management models produced stand development patterns that were consistent with axioms of even-aged stand dynamics.展开更多
文摘This paper established an integrated stand growth model of Mongolian oak(ISGM_oak) using the data from 61 permanent sample plots measured in 1997 and 2007.ISGM_ oak is a group of nonlinear simultaneous equations.The method of nonlinear error-in-variable simultaneous equations is used to estimate the parameters of ISGMoak with the statistical software Forstat 2.0,so the parameter estimation of the group of correlated equations in ISGMoak is unbiased and the equations are compatible.Model validation using bootstrap method showed that both the average relative error and square error are less than 15 percent.The ISGM_ oak model can be used to simulate the stand growth with different values of site index,stand density and to draw stand density management diagram for decision-making.
文摘Models for quantifying the growth responses of black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) to precommercial thinning (PCT) treatments were developed. They accounted for the increased rate of stand development arising from PCT treatments through temporal adjustments to the species and site specific mean dominant height-age functions. Analytically, they utilized a relative height growth modifier consistent with observed density-dependent height repression effects. A phenotypic juvenile age-mature age correlation function was used to account for the intrinsic temporal decline in the magnitude of the PCT effect throughout the rotation. The resultant stand development patterns were in accord with theoretical and empirical expectations when the response models were integrated into algorithmic variants of structural stand density management models.
文摘Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) plantations. The models accounted for the increased rate of stand development arising from the planting of genetically-improved stock through temporal adjustments to the species-specific site-based mean dominant height-age functions. The models utilized a relative height growth modifier based on known estimates of genetic gain. The models also incorporated a phenotypic juvenile age-mature age correlation function in order to account for the intrinsic temporal decline in the magnitude of genetic worth effects throughout the rotation. Integrating the functions into algorithmic variants of structural stand density management models produced stand development patterns that were consistent with axioms of even-aged stand dynamics.