Drivers of within-tree leaf trait variation in a tropical planted forest varying in tree species richness

Research output: Journal contributionsJournal articlesResearchpeer-review

Authors

  • Tobias Proß
  • Helge Bruelheide
  • Catherine Potvin
  • Maria Sporbert
  • Stefan Trogisch
  • Sylvia Haider

In plant ecology, community-weighted trait means are often used as predictors for ecosystem functions. More recently, also within-species trait variation has been confirmed to contribute to ecosystem functioning. We here go even further and assess within-individual trait variation, assuming that every leaf in a plant individually adjusts to its micro-environment. Using forest plots varying in tree species richness (Sardinilla experiment, Panama), we analysed how leaf traits within individual trees vary along the vertical crown gradient. Furthermore, we tested whether niche partitioning in mixed stands results in a decrease of within-species leaf trait variation and whether niche partitioning can be also observed at the level of individual trees. We focused on leaf traits that describe the growth strategy along the conservative-acquisitive spectrum of growth. We found a decrease in within-species variation of specific leaf area (SLA) with increasing neighbourhood species richness. Both sampling height and local neighbourhood richness contributed to explaining within-species leaf trait variation, which however, varied in importance among different species and traits. With increasing sampling height, leaf dry matter content (LDMC), carbon to nitrogen ratio and lignin content increased, while leaf nitrogen concentration (leaf N), SLA, cellulose and hemicellulose decreased. Variation in leaf N decreased with increasing neighbourhood species richness, while the magnitude of within-individual variation of most traits was unaffected by neighbourhood species richness. Our results suggest an increased niche partitioning with increasing species richness both in a plant community and at the level of individual plants. Our findings highlight the importance of including within-individual trait variation to understand biodiversity-ecosystem functioning relationships.

Original languageEnglish
JournalBasic and Applied Ecology
Volume50
Pages (from-to)203-216
Number of pages14
ISSN1439-1791
DOIs
Publication statusPublished - 01.02.2021
Externally publishedYes

Bibliographical note

We thank the site manager of the Sardinilla project José Monteza and the field workers for their continuous on-site support; Lady Mancilla for her help in the administrative coordination and the Smithsonian Tropical Research Institute for land rental and site security; Angie Buchold for her help in the laboratory. The research leading to these results has received funding from the Natural Science and Engineering Council of Canada, and the Canada Research Chair Program to CP as well as the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig (DFG, FZT 118). TP and MS were funded by the graduate scholarship program of Saxony-Anhalt. TP received additional support by the International Research Training Group “TreeDì” jointly funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 319936945/GRK2324 and the University of Chinese Academy of Sciences (UCAS). The manuscript benefitted very much from the constructive comments from the editor and three anonymous reviewers.

Publisher Copyright:
© 2020 Gesellschaft für Ökologie

    Research areas

  • Biology - Biodiversity, leaf economics spectrum, leaf traits, niche theory, sardinilla experiment, Trait variation, tropical plantation forest