湖南省南岳原生性森林群落的研究——Ⅴ.物种多样性与相对多度分布格局

Study of Original Forest Communities in Nanyue of Hunan Province:Ⅴ.Species Diversity and Distribution Pattern of Species Relative Abundance

对湖南省南岳原生性森林群落植物物种进行了研究.结果表明,其多样性水平比较高,接近山地季雨林的水平,其中,群落草本层的多样性水平最低,乔木层和灌木层的较高.在5种不同的原生性森林群落类型中,乔木层和草本层的物种多样性以类型3(包石栎+锐齿槲栎+甜槠+多脉青冈-箬竹-求米草群丛)的最高, 以类型4(甜槠-花竹+云和新木姜子-淡竹叶+莎草群丛)的最低;灌木层物种多样性以类型3(包石栎+锐齿槲栎+甜槠+多脉青冈-箬竹-求米草群丛)的最高, 类型2(长叶石栎+多脉青冈-尾叶山茶-求米草群丛)的最低.植物物种相对多度分布格局的测定结果表明,分割线段模型中的序列-多度模型适宜于拟合乔木层物种与其个体数量之间的关系,对数级数分布模型适宜于拟合乔木层和灌木层;其α指数值较高,说明群落物种多样性水平较高,接近山地季雨林.分析表明, 测定群落植物物种多样性时, 如果仅用1～2个公式计算, 可能会出现错误的结果;此外, 提出了几何级数分布模型--极大值算法.

The paper makes a study of the plant species diversity and distributional pattern on the plant species relative abundance of the original forest community in Nanyue, Hunan Province, The results show that the value of the plant species diversity of the original forest community of this region is rather high and approaches the diversity level of the mountainous seasonal rain forest and that the level of the herb layer of this community is the lowest but the layer of the arbor and shrub are higher. In 5 types of the different associations of the original forest community of this region, the level of the plant species diversity of the layer of the arbor and herb of the association of Lithocarpus cleistocarpus ＋ Quercus aliena var. acuteserrata ＋ Castanopsis eyeri ＋ Cyclobalanopsis multinervis-Indocalamus tessellatus-Oplismenus undulatifolius is the highest but the association of Castanopsis eyeri-Phyllostachys nidularia ＋ Neolitsea aurata var. paraciculata-Lophatherum gracile ＋ Cyperus rotundus is the lowest, and the level of the plant species diversity of the shrub layer of the association of Lithocarpus cleistocarpus＋Quercus aliena var. acuteserrata＋Castanopsis eyeri＋Cyclobalanopsis multinervis-Indocalamus tessdlatus-Oplismenus undulati-folius is the highest but the association of Lithocarpus henryi ＋ Cyclobalanopsis multinervis-Camellia caudata-Oplismenus undulatifolius is the lowest. The results show that the Rankahundance in Broken-stick model is suitable for simulating between the species and its number of individuals of the arbor layer of community, the Log series model is suitable for imitating the layers of arbor and shrub, and the values of α-index approach the level of the species diversity of the mountainous seasonal rain forest. Besides, the ananlysis result showes that the calculative results may be wrong if we only use 1 or 9 formulae to determine the species diversity of the community. Secondly, the authors think that the calculation of k-parameter by using the minimum value i. e. Nmin/N in the method of Geometric series distributional model by Motomura （1932） takes on error results because the value of N is much bigger than the value of Nmin/N , but the calculation of k-parameter by using the minimum value i. e. Nmax/N in the method of geometric series distributional model can solve this problem and is called the maximum method on geometric series distributional model and its formula in the following z N＇i^＊=NCb（1--b）b^i-1 ,Nmax/N=-[（1-b）b^i-1]/ （1-b^2）, where Ni^＊is the expected individual number of the/-species , N is the observed number of the total individuals,i=1,2, ... ,s is the number of species, Cb= （1-b^1）^-1 ,b is a parameter that is the usable resource of species, and Nmax iis the most individual number of some species in a series.