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基于黑龙江省佳木斯市孟家岗林场的12块样地65株人工红松解析木的955个枝解析数据,以Poisson回归模型和负二项回归模型作为备选模型,构建了人工红松二级枝条数量分布模型,并采用AIC、Pseudo-R~2、均方根误差(RMSE)和Vuong检验对模型的拟合优度进行比较.结果表明:每轮一级枝条分布数量集中在3~5个,均值为4个,一级枝条分布数量与人工红松自身的枝条属性相关.一级标准枝上二级枝条分布的离散程度较大,利用全部子回归技术构建二级枝条分布数量模型,最终选择以负二项回归模型为基础的E(Y)=exp(β_0+β_1lnRDINC+β-2RDINC2+β_3HT/DBH+β_4CL+β_5DBH)作为二级枝条分布数量最优预测模型(β为参数;RDINC为相对着枝深度;HT为树高;DBH为胸径;CL为冠长).最优模型的Pseudo-R2为0.79,平均偏差接近于0,平均绝对偏差<7.对于所建立的模型,lnRDINC、CL和DBH的参数为正值,RDINC~2和HT/DBH的为负值,随着RDINC增大,在树冠内二级枝条分布数量存在最大值.总的来说,所建立的人工红松二级枝条分布数量模型的预测精度为96.4%,可以很好地预估该研究区域人工红松二级枝条分布数量,为以后枝条的光合作用和生物量的研究提供了理论基础.
Based on the 955 branch analytical data of 65 artificial Korean pine trees in 12 plots of 12 plots in Mengjigang Forest Farm, Jiamusi City, Heilongjiang Province, Poisson regression model and negative binomial regression model were used as alternatives to construct the secondary branches of artificial Korean pine Distribution model and the AIC, Pseudo-R ~ 2, root mean square error (RMSE) and Vuong test to compare the goodness of fit of the model.The results show that the number of branches per round is concentrated in 3 to 5, The average value is 4. The number of primary branches is related to its own branch attributes.The secondary branches of primary standard branch are more discretely distributed and the secondary branch is used to construct the secondary branch distribution quantity model and the final choice E (Y) = exp (β_0 + β_1lnRDINC + β-2RDINC2 + β_3HT / DBH + β_4CL + β_5DBH) based on the negative binomial regression model was used as the optimal predictor of the number of secondary branches (β was the parameter; RDINC was relative The height of branch, the height of branch, the height of tree branch, DBH as DBH, CL as crown length) .The Pseudo-R2 of the optimal model was 0.79, the average deviation was close to 0 and the mean absolute deviation was less than 7. For the model established, lnRDINC, CL And DBH parameters are positive, RDINC ~ 2 and HT / DBH are negative, with R DINC increased and the maximum number of secondary branches distributed in the crown of the tree crown.In general, the prediction accuracy of the established quantity model of secondary branches of Pinus koraiensis was 96.4%, which could well predict the artificial The distribution of Pinus koraiensis secondary branches provides the theoretical basis for the later photosynthesis and biomass research.