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从林分密度与年龄结构的关系方面应用列联表对阔叶林林分结构变化规律进行研究。通过对福建省750个阔叶林固定样地进行调查,并对收集的资料进行卡方检验、残差分析及log-线性模型的拟合。结果表明:卡方检验中密度与年龄的连带关系明显;残差分析中密度与年龄关系与实际规律的一致性不明显并且主效应估计分析结果与交互作用效应估计之间略有差异,这可能是天然阔叶林受自身因素影响较多而受人为因素影响较少的缘故。
The change of stand structure of broad-leaved forest was studied by using contingency table from the relationship between stand density and age structure. Through the investigation of 750 broad-leaved forest fixed plots in Fujian Province, the data collected were tested by chi-square test, residual analysis and log-linear model fitting. The results show that the relationship between density and age is significant in the chi-square test. The consistency between the relationship of density and age in the residual analysis is not obvious with the actual law and there is a slight difference between the estimation of the main effect and the estimation of the interaction effect, which may be It is the reason that natural broad-leaved forest is more affected by its own factors and less affected by human factors.