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ABSTRACT Accurately representing the relationships between nitrogen supply and photosynthesis is crucial for reliably predicting carbon–nitrogen cycle coupling in Earth System Models (ESMs). Most ESMs assume positive correlations amongst soil nitrogen supply, leaf nitrogen content, and photosynthetic capacity. However, leaf photosynthetic nitrogen demand may influence the leaf nitrogen response to soil nitrogen supply; thus, responses to nitrogen supply are expected to be the largest in environments where demand is the greatest. Using a nutrient addition experiment replicated across 26 sites spanning four continents, we demonstrated that climate variables were stronger predictors of leaf nitrogen content than soil nutrient supply. Leaf nitrogen increased more strongly with soil nitrogen supply in regions with the highest theoretical leaf nitrogen demand, increasing more in colder and drier environments than warmer and wetter environments. Thus, leaf nitrogen responses to nitrogen supply are primarily influenced by climatic gradients in photosynthetic nitrogen demand, an insight that could improve ESM predictions.
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This content will become publicly available on March 18, 2027
Temperature-driven reaction pathways in alkane direct dehydrogenation over metal-free nitrogen doped carbocatalysts
Nitrogen-assembled carbon (NAC) activates C–H bonds through closely spaced graphitic nitrogen sites, enabling efficient dehydrogenation and temperature-dependent kinetics without precious metals, offering a sustainable hydrogen storage platform.
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- Award ID(s):
- 2108306
- PAR ID:
- 10682567
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 17
- Issue:
- 11
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 5684 to 5693
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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