Negative distance-dependence (NDisD) of conspecific seedling mortality is a crucial stabilizing force that regulates plant diversity, but it is still unclear whether and how habitat size shifts the strength of NDisD. Here, we surveyed the seed‒seedling transition process for a total of 25,500 seeds of a local dominant tree species (Castanopsis sclerophylla) on islands with various sizes in a reservoir, the Thousand-island Lake, and on the nearby mainland.
Results/Conclusions
We found significant NDisD on the mainland, large and medium islands, with significantly strengthened NDisD on the medium islands. However, positive distance-dependence of mortality was detected on small islands. Changes in distance-dependence were critically driven by both rodent attack and pathogen infestation, which were significantly affected by habitat size. Our results emphasized the necessity of incorporating the effects of habitat size on distance-dependent regeneration of dominant plant species into the existing frameworks for better predicting the consequences of habitat fragmentation.