Species- and community-level patterns in fine root traits along a 120 000-year soil chronosequence in temperate rain forest
Article first published online: 14 MAR 2011
© 2011 Landcare Research. Journal of Ecology © 2011 British Ecological Society
Journal of Ecology
Volume 99, Issue 4, pages 954–963, July 2011
How to Cite
Holdaway, R. J., Richardson, S. J., Dickie, I. A., Peltzer, D. A. and Coomes, D. A. (2011), Species- and community-level patterns in fine root traits along a 120 000-year soil chronosequence in temperate rain forest. Journal of Ecology, 99: 954–963. doi: 10.1111/j.1365-2745.2011.01821.x
- Issue published online: 14 JUN 2011
- Article first published online: 14 MAR 2011
- Received 20 September 2010; accepted 9 February 2011 Handling Editor: Dali Guo
- environmental gradient;
- Franz Josef chronosequence;
- New Zealand;
- plant–soil (below-ground) interactions;
- plant functional traits;
- specific root length
1. Below-ground plant functional traits regulate plant–soil interactions and may therefore strongly influence ecosystem responses to global change. Despite this, knowledge of how fine-root functional traits vary among plant species and along environmental gradients has lagged far behind our understanding of above-ground traits.
2. We measured species- and community-level root and leaf trait responses for 50 temperate rain forest species from 28 families of ferns, woody and herbaceous angiosperms and conifers, along a soil chronosequence in New Zealand that exhibits a strong gradient in soil nutrient availability. Relationships among species traits (both above- and below-ground) and their distribution along the chronosequence were tested using phylogenetic generalized least-squares regression to account for plant relatedness.
3. Distinctive root trait syndromes were observed; they were closely linked to species’ distribution along the chronosequence. Species growing in the strongly P-limited late stages of the chronosequence had relatively high specific root length (SRL), thin root diameter, high root tissue density, high levels of root branching and low root nutrient concentrations compared to intermediate stages. Species on the youngest site also had high SRL, but had low root tissue density, thick root diameter and high root nutrient concentrations.
4. Species root and leaf nutrient concentrations were positively correlated, reflecting the strong underlying gradient in soil fertility. In contrast, the relationship between SRL and SLA was more complex; there was a weak positive correlation between SRL and SLA, but this conflicted with stronger patterns of increasing SRL and declining SLA with increasing site age.
5. Community-averaged trait values calculated using presence/absence data showed similar trends to the species-level patterns. In contrast, community averages calculated using species abundance-weighted data showed weaker relationships with site age, particularly for morphological traits. This suggests that much of the variation in morphological traits between sites was driven by shifts in the presence of subordinate or ‘rare’ species rather than by changes in the dominant species.
6. Synthesis. Our study demonstrates co-ordinated species- and community-level changes in root traits along a soil chronosequence. These results highlight the influence of soil nutrition on plant functional traits and contribute to our understanding of the drivers of community assembly in a changing environment.