天目山常绿阔叶林空间点格局分形关联维数分析

Spatial Point Pattern Analysis on Fractal Correlation Dimension of Evergreen Broad-leaved Forest in Tianmu Mountain

利用分形中的关联维数D来进行天目山常绿阔叶林种群的空间点格局分析,首先,根据树木坐标建立树木两两之间距离矩阵Dn×n;其次,根据距离矩阵Dn×n计算不同距离步长△r下的距离标度r和r距离标度下树木的数目N(r);最后,计算出关联维数D并根据D得出研究区域的空间分布格局。结果表明,天目山常绿阔叶林研究样区内的树木在空间分布格局上趋于集聚,其关联维数可以用来准确判定空间点格局分布。

Spatial point pattern analysis was conducted on evergreen broadleaved forest in Tianmu Mountain,Zhejiang province by fractal correlation dimension（D）.First of all,a tree-tree distance matrix（Dn×n） was established in accordance with the coordinates of trees.Secondly,distance scale（r） of different step length（△r） and the number of trees N（r） of r was calculated according to the D.Finally,based on the calculation of the correlation dimension D,the spatial point pattern of plant species in the tested area could be calculated.The results showed that point pattern of trees in the study area was clumped,and the correlation dimension could determine the spatial point pattern.