Specific leaf area as a superior predictor of changes in field layer abundance during forest succession


Corresponding author; E-mail johan.dahlgren@botan.su.se


Question: How accurately can a suite of suggested functional traits predict plant species response to succession from semi-open woodland to closed deciduous canopy forest?

Location: Southeastern Sweden.

Methods: Abundance of 46 field-layer plant species in a temperate deciduous forest, measured as frequency of occupied plots, was estimated in 1961, 1970 and 2003. Abundance change over time across species was tested for correlations with functional traits and literature information on habitat preference.

Results: Increase in abundance was positively correlated with specific leaf area (SLA), weakly negatively correlated with seed mass and not significantly correlated with plant height or start, peak and length of the flowering period. Change in abundance was correlated with the Ellenberg light indicator value, whereas no correlations were found with Ellenberg values for nitrogen, calcium and moisture, or forest preference according to the literature.

Conclusions: SLA was a better predictor of how field layer plants responded to succession from semi-open woodland to closed canopy forest than empirically-derived measures of habitat preference. The same holds for SLA in relation to seed size, indicating that interactions in the established life-cycle phase are more important than the recruitment phase for species response to succession.