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Summary Concurrent measurement of multiple foliar traits to assess the full range of trade‐offs among and within taxa and across broad environmental gradients is limited. Leaf spectroscopy can quantify a wide range of foliar functional traits, enabling assessment of interrelationships among traits and with the environment.We analyzed leaf trait measurements from 32 sites along the wide eco‐climatic gradient encompassed by the US National Ecological Observatory Network (NEON). We explored the relationships among 14 foliar traits of 1103 individuals across and within species, and with environmental factors.Across all species pooled, the relationships between leaf economic traits (leaf mass per area, nitrogen) and traits indicative of defense and stress tolerance (phenolics, nonstructural carbohydrates) were weak, but became strong within certain species. Elevation, mean annual temperature and precipitation weakly predicted trait variation across species, although some traits exhibited species‐specific significant relationships with environmental factors.Foliar functional traits vary idiosyncratically and species express diverse combinations of leaf traits to achieve fitness. Leaf spectroscopy offers an effective approach to quantify intra‐species trait variation and covariation, and potentially could be used to improve the characterization of vegetation in Earth system models.
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This content will become publicly available on October 1, 2026
A thinner jacket for frosty and windy climates? Global patterns in leaf cuticle thickness and its environmental associations
Summary Plant cuticles protect the interior tissues from ambient hazards, including desiccation, UV light, physical wear, herbivores and pathogens. Consequently, cuticle properties are shaped by evolutionary selection.We compiled a global dataset of leaf cuticle thickness (CT) and accompanying leaf traits for 1212 species, mostly angiosperms, from 293 sites representing all vegetated continents. We developed and tested 11 hypotheses concerning ecological drivers of interspecific variation in CT.CT showed clear patterning according to latitude, biome, taxonomic family, site climate and other leaf traits. Species with thick leaves and/or high leaf mass per area tended to have thicker cuticles, as did evergreen relative to deciduous woody species, and species from sites that during the growing season were warmer, had fewer frost days and lower wind speeds, and occurred at lower latitudes. CT–environment relationships were notably stronger among nonwoody than woody species.Heavy investment in cuticle may be disadvantaged at sites with high winds and frequent frosts for ‘economic’ or biomechanical reasons, or because of reduced herbivore pressure. Alternatively, cuticles may become more heavily abraded under such conditions. Robust quantification of CT–trait–environment relationships provides new insights into the multiple roles of cuticles, with additional potential use in paleo‐ecological reconstruction.
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- Award ID(s):
- 2017949
- PAR ID:
- 10637420
- Publisher / Repository:
- New Phytologist
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 248
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- 107 to 124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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