关帝山次生林区典型森林交错带物种多样性研究

森林交错带富于高的生物多样性。应用Shannon-Weiner指数、Simpson指数、Margalef指数、Pielou指数，研究了关帝山次生林区森林交错带中处于不同演替阶段的群落物种多样性动态特征，同时对交错带内群落与相邻群落的物种多样性特怔进行了对比分析。结果表明：处于森林演替不同阶段的交错带，在由阔叶林、针阔叶混交林到针叶林的演替过程中，Shannon－Weiner多样性指数、Margalef丰富度指数均表现出单峰变化趋势，在演替中后期的针阔叶混交林阶段，指数值最高。Simpson优势度指数则表现出凹形变化．不同于多样性、丰富度指数，在演替中后期，达到最低值。Pielou均匀度指数表现出下降趋势。交错带内群落与相邻群落相比，Shannon－Weiner多样性指数较高，具有高的物种多样性，边际效应表现为正效应。Margalef丰富度指数变化与Shannon－Weiner多样性指数变化不一致，只在一定程度上证明了边际正效应的影响。两指数共同反映出研究地区的森林交错带内群落具有较高的物种多样性。

Species Diversity in Overlapped Zones of Typical Secondary Forests in Guandishan Mountains

The overlapped zones of forests are highly rich in biological diversity.Shannon-Weiner's diversity index,Simpson's dominance index,Margalef's richness index and Pielou's evenness index were used to study the dynamic diversities of the community species in overlapped zones of secondary forests at different evolution stages in Guandishan Mountain,and comparatively analyze the species diversities of the communities in the overlapped zones and those in the regions in the neighborhood of the overlapped zones.The results showed that the overlapped zones of the forests at different evolution stages transformed from broadleaf forests and needle-leaf-broadleaf mixed forests into needle-leaf forests,their Shannon-Weiner's diversity indexes and Margalef's richness indexes varied in a single-peak pattern with their peaks appearing in needle-leaf-broadleaf mixed forests at the late evolution stage.the Simpson's dominance indexes,differing from the diversity and richness indexes,presented a concave-shaped change with their valley values appearing at the middle to late evolution stage.The Pielou's evenness indexes appeared to decline.The community species in the overlapped zones presented a higher Shannon Weiner's diversity index than those in the regions next to the overlapped zones,thereby having rich species diversity and presenting positive marginal effect.The Margalef's richness indexes varied inconsistently with the Shannon-Weiner 's diversity indexes,and this proved the influence of positive marginal effect,these two indexes both reflected that the overlapped zones under study had high species diversity.