分形理论中的计盒维数、信息维数和关联维数能分别从空间占据程度、格局强度和个体空间关联的尺度变化角度,揭示种群分布格局的尺度变化特征.本文应用以上3个分形维数探讨了福建梅花山国家级自然保护区拟赤杨种群分布格局的多尺度分布规律,计算结果表明,拟赤杨种群的分布格局具有分形特征,其计盒维数为1.0298~1.2982,信息维数为0.9728~1.2464,关联维数为0.5089-0.8047.拟赤杨种群的计盒维数、信息维数较高,而关联维数较小,表明该种群的分布格局强度相对较高,结构相对复杂,具有集聚分布的趋势.
In fractal theory, the box dimension quantifies the spatial occupation ability and degree of population, while the information dimension reflects the scale variation degree of the height architecture and discloses the unevenness of individual height distribution, and the correlation dimension could be a suitable method for quantifying the characteristics of distribution pattern of population. Based on the investigation data of Alniphyllum fortunei populations in the Meihuashan Nature Reserve, Fujian, the fractal properties of distribution pattern were analyzed by using box-counting dimension, information dimension and correlation dimension of fractal theory. The results showed that the distribution pattern of A. fortunei populations could be described by fracta! dimensions. The box-counting dimension ofA. fortunei population ranged between 1. 029 8 and 1. 298 2, the information dimension ranged from 0. 972 8 to 1. 246 4, and the correlation dimension from 0.972 8 to 0.804 7. It showed that the distribution pattern had relatively high box-counting dimension and information dimension, and also had relatively small correlation dimension. According to the results, the distribution pattern of the A. fortunei populations tended to be aggregative.