Nitrogen (N)‐fixing trees are thought to break a basic rule of leaf economics: higher leaf N concentrations do not translate into higher rates of carbon assimilation. Understanding how leaf N affects photosynthesis and water use efficiency (WUE) in this ecologically important group is critical. We grew six N‐fixing and four non‐fixing tree species for 4–5 years at four fertilization treatments in field experiments in temperate and tropical regions to assess how functional type (N fixer vs. non‐fixer) and N limitation affected leaf N and how leaf N affected light‐saturated photosynthesis (
Light and soil nitrogen availability can be strong controls of plant nitrogen (N) fixation, but data on how understory N‐fixing plants respond to these drivers are limited despite their important role in ecosystem N cycling. Furthermore, ecosystem N cycling can be altered by the introduction of species with nutrient use patterns that differ from natives. We assessed how N fixation of two exotic, understory species responded to varying light and soil N environments. We sampled leaf tissue from
- NSF-PAR ID:
- 10405368
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Ecology
- Volume:
- 111
- Issue:
- 4
- ISSN:
- 0022-0477
- Page Range / eLocation ID:
- p. 915-926
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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