深圳福田海桑+无瓣海桑自然林的空间结构分析

采用位置指数(CE)、混交指数(DM)、分异指数(T)以及Ripley’sK方程,探讨了深圳福田红树林保护区海桑+无瓣海桑自然林的空间结构特征。海桑、无瓣海桑、秋茄和桐花树种群都呈现集群分布;海桑-无瓣海桑、海桑-秋茄、海桑-桐花树、桐花树-无瓣海桑以及秋茄-桐花树之间在空间分布上呈现负关联,秋茄-无瓣海桑之间呈现正关联,但这些关联都不显著。海桑和秋茄与其它树种属于中度混交,而无瓣海桑和桐花树与其它树种的混交程度相对较弱。海桑和无瓣海桑个体之间的胸围差异明显,而其它树种个体之间的胸围差异中等。海桑个体之间的树高差异明显,而其它树种个体之间的树高差异中等。采用的空间指数和空间统计技术有效地描述了树种的空间属性。

Analysis of the spatial structure of natural Sonneratia caseolaris+S.apetala forest in Futian, Shenzhen

The spatial structure character of tree populations in a natural Sonneratia caseolaris+S.apetala forest in Futian,Shenzhen was investigated using position index( CE ),mixture index( DM ),differentiation index( T ),and Ripley’s K functions. The horizontal spatial pattern of populations of S.caseolaris,S.apetala,Kandelia candel and Aegiceras corniculatum showed clumped distribution. Negative spatial correlations were found between S.caseolaris and S.apetala,S.caseolaris and K.candel,S.caseolaris and A.corniculatum,A.corniculatum and S.apetala,K.candel and A.corniculatum ,and positive spatial correlations between K.candel and S.caseolaris . However,all these correlations were not statistically significant. In the forest,the mixed degree of S.caseolaris and K.candel and other species was moderate,while that of S.apetala and A.corniculatum and other species relatively low. Individuals of S.caseolaris and S.apetala showed a clear difference in perimeters at breast height,while other species a moderate difference. Individuals of S.caseolaris showed a clear difference in heights,while other species a moderate difference. The spatial indices and techniques used could effectively describe the spatial characteristics of species.