为探讨毛竹(Phyllostachys edulis)入侵对周围森林群落的影响,作者于2005–2011年在天目山自然保护区进行了7年长期定位观测实验,研究了毛竹入侵地森林群落的植物物种多样性变化。结果表明:毛竹入侵对周围森林群落植物物种多样性产生了不利影响:毛竹林乔木层和灌木层植物的Simpson指数小于针阔混交林和毛竹–针阔混交林,而草本层的Simpson指数则大于针阔混交林和毛竹–针阔混交林。植物物种丰富度、Simpson指数和Pielou均匀度指数随时间发生了较大变化:毛竹入侵的森林群落其乔木层和灌木层的物种丰富度、Simpson指数和Pielou均匀度指数显著降低(P〈0.05),草本层的物种丰富度显著提高(P〈0.05),Simpson指数和Pielou均匀度指数未表现出明显的变化。毛竹–针阔混交林去除毛竹后,乔木层和灌木层物种丰富度和Simpson指数增加,草本层物种丰富度、Simpson指数和Pielou均匀度指数明显下降。可见,毛竹入侵使森林群落植物多样性发生实质性的变化,对自然保护区植物群落造成了重大影响。由此可见,要使保护区物种多样性得到保护,除进行科学的管理外,还需要控制毛竹蔓延。
Moso bamboo (Phyllostachys edulis) is an economically important plant, widely cultivated not only for its delicious shoots and versatile culms, but also as an important biomass resource in southern China. However, with its robust growth and strong rhizomes, it has recently been shown to be a problem tree, capable of dominating some forest stands. Indeed, it may displace species within the community it invades with considerable potential impacts. However, little is known about the consequences of its invasion on plant community composition. We compared plant biodiversity change in different communities where we monitored and removed bamboo over a seven years period (2005 to 2011) in Tianmu Mountain Nature Reserve, so as to elucidate the impacts of Moso bamboo invasion. The results showed that Moso bamboo invasion had negative effects on plant communities. Simpson’s Diversity Index in tree and shrub layers of bamboo forest was lower than that of forests consisting of needle and broad-leaved species, and also those containing a mixture of bamboo with needle and broad-leaved plants. However, Simpson’s Diversity Index in the herb layer of bamboo forest was higher than that in the two other forest types. Plant species richness, Simpson’s Diversity Index, and Pielou’s Eveness Index varied greatly among the different forest types over time. In the tree and shrub layers of forests containing bamboo growing with both needle and broad-leaved species, these three indices declined significantly over the monitoring period (P0.05). In contrast, no significant changes of Simpson’s Diversity Index and Pielou’s Eveness Index were exhibited in either forests containing a mixture of needle and broad-leaved plants or in pure bamboo forest (P0.05). Plant species richness increased in the herb layer of forests containing bamboo mixed with needle and broad-leaved species, while Simpson’s Diversity Index and Pielou’s Eveness Index did not change greatly over time. The removal of Moso bamboo resulted in an