天目山物种多样性尺度依赖及其与空间格局关系的多重分形

以浙江省天目山国家级自然保护区为例，采用多尺度分析思想，利用多重分形分析方法，研究了不同尺度下物种多样性的变化、空间分布格局以及多样性与空间格局之间的关系。研究主要得到3方面的结论：（1）物种多样性具有尺度依赖性，随着空间尺度的增大，Shannon-Wiener多样性指数Ⅳ增大，Margalef多样性指数足和均匀度指数E减小；（2）多重分形参数αmin。多重分形谱的变化范围SR等能够定量反映物种的空间分布特征，空间大尺度越大，物种越聚集，空间分布越不均匀；（3）物种多样性与空间格局存在线性或幂函数关系。研究表明多重分形分析定量描述物种空间格局是有效性的，多重分形参数与生物多样性之间的定量关系为研究物种空间格局、生态属性与尺度之间的关系奠定了基础。因此，分形结合传统方法，在生物多样性方面的研究将有很大的潜在价值。

Linking species diversity with spatial scale dependence to spatial patterns using multifractal analysis

This study took the Tianmu Mountain National Natural Preservation Area in western Zhejiang Province as an example 1) to quantify the species diversity with selected species indices including Shannon-Wiener index (H), Margalef index (K) and Evenness index (E) at different spatial scales, 2) to analyze the spatial distribution patterns of the species diversity by multifractal parameters such as the singularity index α, its fractal dimension f(α), the f(α)–α spectrum range (SR) and its symmetry (Dist) using the multifractal theory, and 3) to determine their relationships. Results of nonlinear regression analysis with power functions showed that increasing spatial scale resulted in increasing H but decreasing E and K, indicating that the scale dependence of species diversity existed. By using the multifractal method, it was indicated that species spatial distribution had multifractal features. Moreover, strong linear relationships of the diversity indices H, E and K with α_min and clear nonlinear associations of the diversity indices H, E and K with power functions for SR and Dist were found. Since interactions of the species diversity and the spatial characteristics are very complex, the above mentioned relationships need further validation along with precise explanations of any correlations among their ecological processes.