湖南栎类次生林单木断面积生长模型研究

Individual basal area model of Quercus secondary forest in Hunan Province

以湖南省15个栎类固定样地为研究对象,从6种生长模型中选取栎类断面积最优基础模型,在此基础上构建含林分类型哑变量的栎类单木断面积生长模型。结果表明:栎类单木断面积最优基础模型为Logistic;单木哑变量模型相比于其它基础模型,模型的R^(2)由0.785提高到0.869,RRMSE由16.65%减少到9.28%,模型精度显著提高;在栎类+杉木林林分类型中,栎类断面积生长较快,生长速率优于其它2种林分类型。含林分类型的哑变量模型在拟合优度方面高于基础模型,说明栎类断面积生长受林分类型的影响,构建栎类单木断面积模型可为不同林分类型下栎类的生长预估提供参考。

Based on 15 fixed samples of Quercus species in Hunan province,the optimal foundation model of basal area was selected from 6 growth models,and the individual growth model of basal area with dumb variable of stand type was thus established.The results showed that the Logistic model was the optimal foundation model of basal area.Compared with the basic model,the R^(2) of dummy variable model was increased from 0.785 to 0.869,and the RRMSE was reduced from 16.65% to 9.28%,increasing the model accuracy.The growth rate of quercus in mixed Quercus and Cunninghamia lanceolate forest was higher than that of other two stand types.The dummy variable model was higher than the basic model in the goodness of fit,indicating that the growth of basal area was affected by stand type.The individual growth model of basal area can provide reference for the growth prediction of Quercus in different stand types.