县级区域材种出材率表编制中削度方程的建立研究

Study on Establishing Regressive Equation in Tabulation of Individual Timber's Percentage of Out-turn at County Level

建立削度方程是编制材种出材率表的基础.以寻甸县境内的人工华山松造材样木为研究对象,选择有代表性的或拟合效果较好的一些削度方程对其削度方程进行拟合,根据精度分析,选择d/D=0.076 7+2.259 7[(H-h)/(H-1.3)]-3.070 7[(H-h)/(H-1.3)]2+1.716 9[(H-h)/(H-1.3)]3模型作为编制华山松人工林单株木材种出材率表的最佳削度方程.经分别与检验样本树干的各部位直径实测值与削度方程理论估计值的差异进行检验,表明模型无系统偏差,检验指标的绝对值小,方程的拟合效果好,具有较好的适用性.

The establishing of regressive equation is a basis for working out a table of timber species per-centage of out-turn. Taking planted Pinus armandii being timber sample as an objective, the study selects some representative or excellent result of regressive equations fitting with Pinus armandii＇s regressive equation. According to precision analysis, it chooses d/D = 0.07607 ＋ 2. 259 7 [（H-h）/（H-1.3）]-3.0707[（H-h）/（H-1.3）]2 ＋1.716 9 [（H-h）/（H-1.3）]3 model as optimal equation for tabularizing a table of timber species Pinus armandii＇ s percentage of out-turn in Xudian county. The examination shows that the model has not systematic error with little absolute value of examination index, better outcome of equation＇ s fitting as well as ideal suitability.