浙江楠纯林与异龄混交林群落结构比较

Comparisonof the Community Structure between Pure and Uneven-agedmixed Phoebe chekiangensis Forests

以天童山13年生浙江楠人工纯林与异龄混交林为研究对象,从生态学的视角比较分析其林分发育、林木竞争分化、树高/胸径比值和优势木生长的特征。结果表明：与纯林相比,异龄混交龄林生长优势显著;林分平均胸径生长量提高1.8%,单株材积生长提高7.4%。树高胸径关系分析表明,异龄混交林中浙江楠个体的高生长得到显著促进,其树高生长量比纯林提高8.4%;异龄混交林、纯林中浙江楠1~5级木的比例大小排序分别为3级（43.7%）〉2级（26.5%）〉4级（15.7%）〉1级（12.9%）〉5级（1.2%）;3级（34.7%）〉2级（25.6%）〉4级（20.0%）〉1级（18.2%）〉5级（1.2%）;直径结构都显正态分布,纯林分化程度大于异龄林。浙江楠纯林、异龄林优势木分别占总株数的18.2%、12.9%,分别提供51.1%、35.4%的蓄积量,反映了自疏效应导致的优势木贡献。

In this study ,the 13 year growth artificial pure forests of Phoebe chekiangensis and unevenaged mixed forests in TianTong mountain has been selected as research objectives ,and we analyzed the characteristics of forest stands development ,competitive dif-ferentiation of forest ,tree height/diameter ratio and the growth of dominated trees.Our results showed that ,unevenaged mixed forests had a significantly growth advantage compared with pure forests;Average breast diameter growth increment of forest stands increased 1.8%,and individual volume reached 7.4%.Analyting the results of relationship between tree height and average breast diameter , we kown the individual growth of height of Phoebe chekiangensis in unevenaged mixed forests had been significantly boosted ,and tree height growth was higher with 8.4% than pure forests;Proportion sequence of 1~5 level forest of Phoebe chekiangensis in uneve-naged mixed forests and pure forest followed the series that 3（43.7%）〉2（26.5%）〉（15.7%）〉1（12.9%） 〉5（1.2%）,3 （34.7%）〉;2（25.6%） 〉4（20.0%）〉1（18.2%）〉5（1.2%）,respectively.The diameter structures of forests all followed normal distribution ,but the degree of differentiation of pure forest was greater than unevenaged mixed forests .Artificial pure forests and unevenaged dominated forest accounted for 18.2%and 12.9%for the total,and accumulated 51.1%and 35.4%growing stock for total,respectively,indicating the dominated contribution induced by self-thinning effect.