Seedlings and trees respond differently to tree plantation-driven forest fragmentation: Fragment isolation affects seedlings, while fragment area affects trees

作者：Mengli Li, Xinyu Zhu, Xueting Li, Fengqun Meng · 发表于：Forest Ecology and Management · 年份：2025 · DOI：10.1016/j.foreco.2025.122789 · 被引用次数：3 · 研究领域：Forest ecology and management、Forest Management and Policy、Conservation, Biodiversity, and Resource Management

The global expansion of tree plantations, particularly in tropical and subtropical regions, has fragmented natural forests. Understanding plant diversity patterns and underlying mechanisms in these fragmented "islands" is crucial for biodiversity conservation. We examined the species–isolation relationships (hereafter SIR) and species–area relationships (hereafter SAR) for all woody plants, trees and seedlings in a tree plantation-driven fragmented system in Guangxi, China. We also investigated the underlying mechanisms responsible for the observed SIR and SAR. We found a negative SIR and a positive SAR for all woody plants. However, seedlings and trees responded differently to tree plantation-driven fragmentation: seedlings exhibited a negative SIR but no SAR, while trees showed a positive SAR but no SIR. The negative SIR for seedlings was driven by a response of animal-dispersed species to isolation, evidenced by a negative SIR for animal-dispersed seedlings but no SIR for non-animal-dispersed seedlings. This isolation effect on seedlings likely reflects limitations in plant regeneration within fragmented forests, potentially due to a decline in seed dispersers. The positive SAR for trees was linked to greater heterogeneity in community composition in larger fragments, which in turn was associated with higher levels of overall habitat heterogeneity. Our results suggest that the SAR for trees is primarily driven by habitat heterogeneity. Restoration efforts should focus on i...