卧龙自然保护区大熊猫栖息地植物群落多样性研究 Ⅳ.人为干扰对群落物种多样性的影响

Diversity of the Plant Community of Giant Pandas' Habitat in Wolong Nature Reserve. Ⅳ.The Effects of Human Disturbance on the Species Diversity of the Plant Community

本文从生物多样性角度研究人为干扰(主要是森林采伐)对卧龙自然保护区野生大熊猫栖息地的影响,采用样方法、物种多样性指数以及SPSS 13.0统计软件调查和分析了64个植物群落数据。结果表明:人为干扰影响着大熊猫栖息地森林植物群落的物种多样性,尤其是影响林分各层次的植物组分。不同采伐方式中皆伐的物种多样性指数高于择伐与原始森林,物种数平均分别是原始林20.78±9.07、皆伐27.69±7.75和择伐26.62±8.81,但仅物种数和Margelef指数呈显著性差异,其他指数差异不显著;不同采伐时间的物种多样性指数波动性较大,20世纪90年代初期明显高于其他年代和原始森林,这不仅与采伐方式有关,而且同大熊猫主食竹种的生命规律联系紧密,其各指数之间的统计假设检验结果与不同采伐方式相同。

In this paper, researches were made on the impacts of human disturbance （mostly forest logging） on the giant pandas＇ （Ailuropoda rnelanoleuca ） habitat in Wolong Nature Reserve. The 64 plots of the plant community were investigated and analyzed by use of the sampling method, and species diversity index and SPSS 13.0 software. The results have shown that human disturbance affects the species diversity of the plant communities in giant pandas＇ habitat, especially on the plant components of each layer in plant community. The clear-cutting reduced badly the species diversity indices of arbor layer,and it was propitious to increase the species diversity indices of shrub and grass layers. The species diversity indices of arbor layer of the selective logging forest were more than those of the clearcutting forest, and little than those of the primary forest. The plant components of forest underlayers were abundant in the later-day cutting forest. Along with the prolonging of forest succession, the species diversity indices of arbor layer were mounting up, but those of shrub and grass layers would reduce. The species diversity index of the clear-cutting forest was higher than that of the selective logging forest and primary forest. The number of species was 27.69 ±7.75 in primary forest, 20.78± 9.07 in clear-cutting forest, and 26.62 ± 8.81 in selective logging forest, respectively. The number of species and Margelef＇s indices displayed marked differences, and the other indices were not notable in different logging types. The species diversity indices of different logging times were were more fluctuant, the indices of the initial stages of the 1990＇ s exceeded obviously those of the other years and the primary forest. And this was closely relative to the logging types and the growth pattern of bamboos as the giant pandas＇ staple diets. The results of the statistical hypothesis testing of the different logging times were similar to those of the different logging types.