闽楠天然次生林自然更新的影响因子研究

Study on Factors Affecting Natural Regeneration of Natural Secondary Phoebe bournei Forest

[目的]分析闽楠天然次生林自然更新与环境因子之间的关系,为其科学经营及保护提供参考依据。[方法]以江西省吉安市闽楠天然次生林为研究对象,通过标准地调查获取数据,运用多元数量化模型I建立闽楠幼树幼苗重要值与环境因子的关系模型,采用单因素方差分析单个环境因子对闽楠幼树幼苗更新的影响。[结果]研究表明:密度(闽楠下种母树株数、郁闭度、株数密度)、坡位、腐殖质层厚度、坡向、林下植被盖度、凋落物层厚度是影响闽楠天然次生林自然更新的主要因素,偏相关系数在0.325 7 0.715 7之间,t检验结果为极显著或显著;模型复相关系数为0.966,F检验结果为极显著(F=30.96^(**))。[结论]闽楠下种母树株数对其幼树幼苗的更新起着最主要的作用,而郁闭度与株数密度过高或过低、凋落物层越厚、腐殖质层越薄、林下植被盖度越大均不利于其自然更新,同时,半阴坡、下坡位条件下的闽楠幼树幼苗的更新好于其它坡向与坡位。为促进闽楠幼树幼苗的自然更新,林分中闽楠下种母树应保留200株·hm^(-2)以上,以及对郁闭度、林下植被盖度及凋落物层厚度等实施相应的调控措施。

[ Objective ] To analyze the relationships between natural regeneration of Phoebe bournei and environmen- tal factors in order to provide references for protecting and managing natural secondary P. bournei forest. [ Method ] Based on data of sample plot investigation, a relationship model between saplings and seedlings importance values and environmental factors was established by quantitative model I, and the effeet of single environmental factor on natural regeneration was explored by using one-way ANOVA method in Ji＇ an Country, Jiangxi Province. [ Result ] The results showed that the main elements affecting natural regeneration were density （amount of P. bournei parent tree, canopy density, tree density） , position of slope, humus layer thickness, aspect of slope, coverage of under- story vegetation, litter layer thickness, with the partial correlation coefficients being 0.325 7 -0.715 7, which were significant or very significant by t test. The multiple correlation coefficient of the model reached 0. 966, showing very role significant by F test （ F = 30.96 ＊＊ ）. [ Conclusion ] The amount of P. bournei parent tree plays an important in natural regeneration of saplings and seedlings, while higher or lower of canopy density and tree density, thicnatural regeneration of saplings and seedlings.