Abstract
The plant economics spectrum proposes that ecological traits are functionally coordinated and adapt along environmental gradients. However, empirical evidence is mixed about whether aboveground and root traits are consistently linked and which environmental factors drive functional responses. Here we measure the strength of relationships between aboveground and root traits, and examine whether community-weighted mean trait values are adapted along gradients of light and soil fertility, based on the seedling censuses of 57 species in a subtropical forest. We found that aboveground traits were good predictors of root traits; specific leaf area, dry matter, nitrogen and phosphorus content were strongly correlated with root tissue density and specific root length. Traits showed patterns of adaptation along the gradients of soil fertility and light; species with fast resource-acquisitive strategies were more strongly associated with high soil phosphorus, potassium, openness, and with low nitrogen, organic matter conditions. This demonstrates the potential to estimate belowground traits from known aboveground traits in seedling communities, and suggests that soil fertility is one of the main factors driving functional responses. Our results extend our understanding of how ecological strategies shape potential responses of plant communities to environmental change.
Highlights
Functional traits can be powerful indicators of the ecological strategies of plant species (Wright et al, 2004; Freschet et al, 2010; de la Riva et al, 2016), and trait-based approaches have provided important insights toward understand what drives the structure of biological communities (Messier et al, 2017; Umana et al, 2017)
Aboveground traits were good predictors of some key root traits in the univariate phylogenetic generalized least squares (PGLS) models (Table 2), for root tissue density (RTD), specific root area (SRA), and specific root length (SRL), since we found that most of the aboveground traits, such as leaf area ratio (LAR), LDMC, leaf nitrogen content (LN), LP, specific leaf area (SLA), and specific stem length (SSL) were correlated with each of them
Because limiting resources should be the main ecological factors that drive the functional response of plants (PerezRamos et al, 2012), our results suggest that P and K may be the most limiting soil nutrients in this subtropical forest, so that species adapted for resource acquisition were more successful in the environments where those nutrients were abundant
Summary
Functional traits can be powerful indicators of the ecological strategies of plant species (Wright et al, 2004; Freschet et al, 2010; de la Riva et al, 2016), and trait-based approaches have provided important insights toward understand what drives the structure of biological communities (Messier et al, 2017; Umana et al, 2017). Plant economics spectrum (PES) theory attempts to integrate leaf, stem, and root traits to explain plant ecological strategies (Reich, 2014; Diaz et al, 2016) It predicts that (1) the leaf, stem, and root traits are correlated with each other and coordinated across different organs, and (2) functional traits should have adaptive significance along resource gradients. This leads to two inferences: (1) because all organs should be consistently resource-acquisitive or resource-conservative for all resources, readily measured aboveground traits should be useful predictors of root traits that are more difficult to measure; and (2) if traits from different organs are coordinated, they should response to environmental gradients consistently (e.g., fastgrowing, resource-acquisitive species should be more abundant in resource-rich environments, and slow-growing, resourceconservative species should be more abundant in resource-poor environments) (Reich, 2014; Kramer-Walter et al, 2016)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
