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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 19, 2026
A mechanistic model for determining factors that influence inorganic nitrogen fate in corn cultivation
A model of nitrogen biogeochemical cycling in agriculture soil at the field scale for assessing how crop management practices affect nitrogen fertilizer fate and transport.
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- Award ID(s):
- 2133423
- PAR ID:
- 10634248
- Publisher / Repository:
- Environmental Science: Processes & Impacts
- Date Published:
- Journal Name:
- Environmental Science: Processes & Impacts
- Volume:
- 27
- Issue:
- 3
- ISSN:
- 2050-7887
- Page Range / eLocation ID:
- 549 to 562
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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