Speaker
Description
Trait-based ecology assumes that functional traits help to understand how organisms influence ecosystem processes. The focus has classically been on trait differences between species, but, as the range of variation within species (intraspecific and intraindividual trait variability) is highly plastic, it may be more likely to respond to species richness in communities to mediate coexistence. However, we lack empirical evidence on how these sources of trait variation shape tree-tree interactions and how they contribute to the functional diversity of communities.
We sampled 4,608 leaves from 384 trees belonging to eight tree species along an experimental tree species richness gradient in subtropical China (BEF-China). To assign trait values to leaves, we conducted leaf spectroscopy and used deep learning to predict values for seven leaf functional traits. Functional indices were used to assess intraspecific and intraindividual trait variability and linear mixed-effect models and structural equation modelling were used to study how intraspecific overlap is mediated by intraspecific and intraindividual trait variability along the tree richness gradient. Additionally, we identified which sources of variation within species strongly affect community functional diversity by comparing the functional diversity of observed communities and virtual communities in which different sources of trait variation were randomized.
Intraspecific trait variability responded to tree species richness and was the main supporter of intraspecific complementarity. On the contrary, responses of intraindividual leaf variability to tree species richness were weak and were mainly related to the stomatal strategy of the leaves. Last, our results suggest that functional richness was influenced by intraspecific variability while functional divergence was influenced by intraindividual variability, especially at the higher levels of tree species richness.
We suggest that trait variability occurring at the finest scales could have ecological relevance for intraspecific interactions, improve the efficiency in the water use strategy and shape the functional diversity of assemblages.
| Status Group | Doctoral Researcher |
|---|
