A long-standing paradigm in ecology is that species diversity in a community accrues over succession. Various mechanisms could contribute to this accumulation, including amelioration of habitat conditions, buildup of community complexity, and increasing competition. Central to these mechanisms are the processes that regulate neighborhood interactions around species of different functional groups (e.g., early vs. late successional species). However, there is little understanding how such different species may accumulate neighborhood diversity and thus contributes to maintaining diversity in a community.
In this study, we measured the neighborhood diversity for ten species of different successional stages to test the roles of species of different successional stages in neighborhood accumulation in a subtropical forest. The neighborhood diversity was assessed by species richness, phylogenetic dissimilarity and species composition.
Results/Conclusions
Our results showed that early successional species accumulate higher neighborhood species richness and beta diversity and are more closely related than late successional species compared with null expectations. Moreover, we found pioneer species mainly accumulate diversity of saplings rather than adults, suggesting that seed dispersal and seedling recruitment related processes may be responsible for this pattern. The larger departures than homogeneous Poisson null model implying that small-scale habitat heterogeneity contribute more to the neighborhood diversity accumulation than species interactions.
This study concluded that early successional species play more important role than expected in neighborhood diversity accumulation driven by habitat heterogeneity and competition.