神农架地区常绿落叶阔叶混交林树种更新研究

The Regeneration of Tree Species in the Mixed Evergreen-deciduous Broad-leaved Forests in the Shennongjia Mountains, Hubei Province

在神农架山区山体的中部 ,选取代表性的常绿落叶阔叶混交林样地 ,总面积为 2 .4hm2。在样地中对出现的林窗斑块以及相邻的对照的非林窗样方进行群落学调查。记录乔木树种的种类、胸径和高度以及它的幼苗和幼树的高度、数量。按照树种在林窗内外重要值的位序差值将群落出现的乔木层树种划分为 4类生态种组 ,其中 ,对林窗强烈正更新反应的树种有 6种 ,强烈负更新反应的树种 9种 ,中等更新反应的 9种 ,不明显更新反应的 1 0种。林窗内外乔木树种生态种组的组成明显不同。不同生态种组树种的幼苗在林窗与非林窗斑块中的更新表现出显著的差别。对神农架地区常绿落叶阔叶混交林树种更新的反应和过程的研究结果支持了林窗

In the mixed evergreen\|deciduous broad\|leaved forests in Shennongjia Mountains, Hubei Province, China, we established the 2 4 hm 2 plot on the middle slope of mountain. Within this plot, gap patches and the non\|gap controlled quadrat near each gap patch were sampled. For each gap patch and non\|gap quadrat, height and number of seedlings and saplings, and DBH and height of the major tree species were measured. According to difference value in the order of Importance Value of the major trees between gap and non\|gap patches, thirty\|four major tree species in the whole community were classified into four ecological groups of species. Six tree species belong to the trees with strong positive regeneration response to gaps, nine tree species belong to the trees with strong negative regeneration response to gaps, nine tree species belong to the trees with moderate regeneration response to gaps and ten tree species belong to the trees with non\|significant regeneration response to gaps. We found that the composition of ecological groups of species in gap patches was distinctly different from that in non\|gap patches. Recruitment of the seedlings for the different ecological groups of species in gap patches differed from that in non\|gap patches significantly. Based on the analyses of the generation response and process of major tree species, gap\|partitioning hypothesis is supported by this study.