Abstract: [Objective] Studying spatial pattern of plants may provide significant insights into processes and mechanisms that maintain species coexistence and biodiversity maintenance. Accordingly, intra- and interspecific spatial association patterns were assessed in a fully mapped 30-ha field plot in a broad-leaved korean pine forest in Jiaohe, Jilin Province.[Method] We applied spatial point pattern analysis and used summary statistics such as the pair-correlation function, Ripley's K-function and the distribution function of nearest neighbor distances. Complete spatial randomness (CSR) was applied as a first null model to test overall intraspecific and interspecific association patterns at scales of 0-50 m. The heterogeneous Poisson (HP) null model was also used to test small-scale intraspecific and interspecific association patterns at scales of 0-30 m (after evaluating larger-scale patterns).[Result] The CSR null model revealed significant clustering of species at most scales. The HP null model revealed significant aggregations mainly within neighborhood distances of less than 10 m. The percentage of aggregated patterns decreased sharply with increasing spatial scale. Conversely, the percentage of species exhibiting a random or regular pattern increased with increasing spatial scale. This result shows that individuals tend to gather in the vicinity of conspecific species, exhibiting intraspecific aggregation. Segregation and partial overlap were prominent in interspecific association types. Few species pairs showed interspecific mixing. The proportion of species showing negative associations (repulsion) was found to be greater than that of positive associations (attraction) at most scales. This is an indication that the individuals of different species tend to be separated in space and that they show negative association with few opportunities for direct interaction between interspecific individuals.[Conclusion] This study presents a comprehensive analysis of the spatial species-association structure in a temperate broad-leaved Korean pine forest in Jiaohe, Jilin Province. Intraspecific aggregation and interspecific segregation were the main patterns of spatial structure in the 30-study area. The spatial segregation between different species weakens interspecific competition which may prevent a competitive exclusion of dominant against disadvantaged species and facilitates species coexistence and biodiversity maintenance.

Key words: spatial distribution patterns, species associations, spatial point pattern analysis, broad-leaved korean pine forest, species coexistence