Yuanfa Li, Liting Wei
Spatial patterns at the structural type level of an old-growth forest in South China
Dendrobiology 2025, vol. 94: 126-138
https://doi.org/10.12657/denbio.094.009
Abstract:
Spatial structure plays a vital role in forest operation, community dynamics, biodiversity conservation, and ecological functions, and it has been well documented at population, community, and regional levels. However, most studies on spatial structure focus on tree attributes without considering the relationships among neighbors. Based on the position, species, and size of neighboring trees, forest spatial structure can be classified into distribution, mixture, and differentiation classes. We analyzed the spatial patterns of these types in a 6-ha old-growth forest plot in southern China using pair correlation functions, mark correlation functions, and mark variogram functions. The results revealed that: (1) The distribution classes primarily exhibited aggregated patterns, with random associations dominating their relationships; (2) The mingling classes also exhibited aggregation, with spatial associations shifting from attraction to repulsion as the mingling degree increased; (3) The spatial structure of the differentiation classes was predominantly characterized by aggregation and random association. Intraspecific aggregation and small-tree aggregation were common features across all structural types. These findings are well explained by forest ecology theories such as dispersal limitation, mingling-size hypothesis, and the Janzen–Connell hypothesis, suggesting that different tree groups play distinct roles in forest communities. This study enhances our understanding of spatial structure in natural forest ecosystems and contributes to the monitoring, assessment, and management of forest resources
Keywords: distribution pattern, nearest neighbors, size differentiation, species mixture, structural type