福建木荷地上部分相容性生物量模型研究

The Aboveground Compatible Biomass Model of Schima superba in Fujian Province

基于160株木荷样木实测数据,以胸径、树高以及两者的组合变量作为模型的自变量,通过2种方案(总量控制方案与代数和控制方案)非线性度量误差联立方程组估计法,并采用加权回归消除异方差,构建木荷一元、二元独立与相容性生物量模型;基于一元相容性模型,探讨各组分生物量相对于地上总生物量的分配规律。结果表明:2种方案建立的相容性生物量模型拟合效果与估计精度良好且各组分生物量模型拟合情况基本一致,R^2≥0.845、MPE≤4.592%,综合分析采用代数和控制方案较好;在各组分独立模型与相容性模型中,二元生物量模型拟合效果明显优于一元模型,且以D^2H为自变量的二元模型最优;2种方案相容性生物量模型各器官生物量分配规律基本相同,随着胸径增大,树干、干材生物量占地上总量比先增大最后趋于稳定,树冠、树皮和树叶生物量占比先减小最后趋于稳定,树枝生物量占比变化不大;当胸径≥30 cm,占比趋于稳定,树干、干材、树皮、树冠、树枝和树叶生物量占比为74.5%~75.2%、68.9%~69.2%、5.6%~6.1%、24.8%~25.4%、21.5%~22.8%和2.6%~3.2%。

Based on the data of 160 Schima superba samples,taking DBH(D),tree height(H)and their combined variables(D^2H)as independent variables of the model.Two schemes(Total Control and Algebraic Sum Control)are used to estimate the simultaneous equations of non-linear measurement errors,and weighted regression was used to eliminate heteroscedasticity.The univariate and binary independent and compatible biomass models of Schima superba were constructed.Based on the univariate compatible model,the distribution of each component biomass to the total aboveground biomass was analyzed.The results showed that the fitted results of the compatible biomass models established by the 2 schemes were good,and the fitted results of each component biomass model were basically the same.The R^2 value was more than 0.845,and the MPE value was less than 4.592%.Algebra and control schemes are better for comprehensive analysis.In the independent model and compatibility model,the fitting effect of binary biomass model is better than that of univariate model,and the binary model with D^2H as independent variable is the best.In the 2 schemes,the distribution of biomass of each organ in the compatible biomass model is basically the same.With the increase of DBH,the ratio of biomass of trunk and trunk to total aboveground biomass increases first and then tends to be stable.The proportion of biomass of crown,bark and leaf decreases first and then tends to be stable;while DBH is more than 30 cm,the proportion of biomass of branches does not change much,the biomass ratios of trunk,trunk,bark,crown,branch and leaf were74.5%-75.2%,68.9%-69.2%,5.6%-6.1%,24.8%-25.4%,21.5%-22.8%and 2.6%-3.2%.