生境异质性对鼎湖山植物群落多样性的影响

根据鼎湖山永久样地的调查资料 ,探讨生境尺度异质性对植物群落物种多样性的影响。结果显示多样性指数随着生境异质性的变化而产生较大的差异。群落多样性指数随地形差异而表现出南坡 >北坡、坡底>坡中 >坡顶的变化趋势。海拔梯度与多样性指数的线性关系不很明显 ,但仍有随海拔升高而下降的倾向。以Shannon-Wiener多样性指数为权重参数的主成分分析结果表明 ,影响植物群落多样性指数的第一主成分中 ,干扰体系和坡向造成的异质性生境影响最大 ,其贡献率为 4 2 .95 %。影响群落多样性的第二主成分因子主要是土壤类型和海拔梯度的变化 ,贡献率为 2 6 .2 4 %。

Effects of habitat heterogeneity on forest community diversity in Dinghushan Biosphere Reserve

Based on long-time investigation of permanent plot in Dinghushan Biosphere Reserve,we detected the effects of habitat heterogeneity on plant community diversity. Results indicated that diversity index showed a great difference in different forest communities that caused by variation of habitat attributes. Community diversity order correlated with topography attributes was:southern exposure>northern exposure,lower slope>middle slope>upper slope. Diversity index showed a tendency that value of diversity index decreased with increasing elevation,though linear correlation between them was not clear. Results of principal component analyses showed that disturbance regimes and exposure were the important factors as the first component had effects on community diversity, and its contribution is up to 42.95%. The second principal component (contribution is up to 26.24%) may reflect soil types and elevation gradient correlated with community diversity.