| The particle selection Jiamusi City, Heilongjiang Province, in the 2004-2005 Forest Mengjiagang 16 sylvestris plantations totaling 30 fixed criteria to parse wooden relevant data for the study. By parsing trees, Setsuko Setsuko growth process for data analysis and data discs sylvestris plantations and Setsuko reflected in the size of its variation, as well as outside the industry surveys artificial Pinus sylvestris Setsuko related After the measurement data factor data obtained preliminary analysis, drawing on the results of previous studies, by constructing a single wood Setsuko diameter, Setsuko angles, sound knots and loose section length length prediction model to predict the trees reach Setsuko size the purpose. By observing and finishing stands artificial pruning intensity and duration of Mongolian pine plantation intervals to achieve the purpose of the development of high-precision sylvestris plantations pruning techniques. To provide a reference for the cultivation of Mongolian pine plantation forestry production no section Wuliangcai to improve timber volume and wood quality.Pinus sylvestris is one of the main conifer species in Northeast China, is also very important timber species, and therefore simulate the artificial Pinus sylvestris Setsuko important. In this paper, a detailed analysis of each sub-section of the artificial Pinus sylvestris measure factor, based on the theory of linear mixed effects models were constructed artificial Scotch Pine Knot diameter model, Setsuko angle model, sound knots and loose section length model length model. Model parameters with advanced statistical software SAS9.3 estimated.In this study, mainly conifers forest northeast of artificial Pinus sylvestris Setsuko size model is the model, the main sub-section diameter to fit the model, Setsuko angle model, sound knots length model, loose section length model. To improve the fit and predictive ability of the model results, this study used linear mixed models were fitted to all models. Due to the size of the artificial Pinus sylvestris Setsuko can fully reflect the merits of the material, can reflect on the stand space utilization wood branches, artificial Pinus sylvestris Setsuko model has important practical significance. The results show that, after constructing a linear mixed-effects model, the effect of the fixed effects model residual plots artificial Pinus sylvestris four knots forecast models and mixed effects models, mixed effects model is better than the fixed effects model. Parametric test results can be seen from the model, the standard deviation in the model parameters are the vast majority of small, good stability; from the test results, Setsuko diameter model of artificial Pinus sylvestris, Setsuko angle model and sound section length predictive ability of the model is better, and the poor predictive ability of the loose section length model, which may get loose and there is a large section of the length of the data errors have a great relationship. In summary, the size of the prediction model Setsuko northeast artificial Pinus sylvestris forest conifers Setsuko able to predict a good size. As used herein, the amount of data due to the smaller, so there is no Establishing plantation tree height, branch prediction model and stand high effective crown height prediction model. To a certain extent, the establishment of the statistical model can be inferred on a large scale, but the problems are due to the model there will always be some errors in the estimated value of the height variation after artificial Pinus sylvestris Setsuko is calculated there will be a large error, so this sort of stand by observing and artificial pruning intensity and time interval sylvestris plantations develop Mongolian pine plantation pruning to achieve the purpose of high-precision technology. |
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