Intraspecific variability in functional traits matters: case study of Scots pine

Area of Science:

• Ecology
• Forest Science
• Plant Trait Ecology

Background:

• Intraspecific trait variability is key to species' ecological plasticity but its community-level implications are understudied.
• Functional traits influence ecosystem processes and species interactions.

Purpose of the Study:

• To quantify intraspecific functional trait variability in Scots pine (Pinus sylvestris).
• To compare this variability with interspecific variation in Catalonia, Spain.
• To investigate trait relationships and their links to stand/climatic variables and radial growth.

Main Methods:

• Analysis of five functional traits: wood density (WD), maximum tree height (H max), leaf nitrogen content (Nmass), specific leaf area (SLA), and leaf biomass-to-sapwood area ratio (B L:A S).
• Utilized data from 406 plots in the Ecological and Forest Inventory of Catalonia (IEFC).
• Statistical modeling to assess trait correlations and their impact on radial growth.

Main Results:

• Substantial intraspecific trait variation observed across all measured traits (CVs 8%-24%).
• Observed trait correlations sometimes differed from interspecific patterns (e.g., H max and WD positively related).
• Models explained 47% of the spatial variability in Scots pine radial growth, highlighting trait variation's role.

Conclusions:

• Intraspecific trait variation in Scots pine is substantial and strongly linked to spatial growth patterns.
• Factors influencing intraspecific trait variation follow a hierarchical structure.
• Inclusion of intraspecific trait variation is vital for predictive models of vegetation dynamics and climate change responses.