Ecological network analysis reveals complex responses of tree species life stage interactions to stand variables

Abstract

Tree interactions are essential for the structure, dynamics, and function of forest ecosystems, but variations in the architecture of life-stage interaction networks (LSINs) across forests is unclear. Here, we constructed 16 LSINs in the mountainous forests of northwest Hebei, China based on crown overlap from four mixed forests with two dominant tree species. Our results show that LSINs decrease the complexity of stand densities and basal areas due to the interaction cluster differentiation. In addition, we found that mature trees and saplings play different roles, the first acting as “hub” life stages with high connectivity and the second, as “bridges” controlling information flow with high centrality. Across the forests, life stages with higher importance showed better parameter stability within LSINs. These results reveal that the structure of tree interactions among life stages is highly related to stand variables. Our efforts contribute to the understanding of LSIN complexity and provide a basis for further research on tree interactions in complex forest communities.

Keywords

Tree interactions / Life stages / Interaction networks / Ecological complexity

References

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