Biogeography of community canopy leaf traits and their links to global forest photosynthesis
- Feng Jiang
- Bernhard Schmid
- Xucai Pu
- Chengjun Ji
- Zehao Shen
- Zhiyao Tang
- Xiangping Wang
- Chengyang Zheng
- Biao Zhu
- Peter B. Reich
- Jingyun Fang
- Zhiheng Wang
2026-07-10
Leaf traits influence biotic interactions and ecosystem functions in forests. However, biogeographic drivers of leaf traits remain highly uncertain, limiting their integration into global vegetation models. Using a global dataset of forest plots, we show that community canopy leaf traits align along three dimensions: leaf economy, leaf density, and nitrogen-to-phosphorus (N:P) ratio. Changes in these trait dimensions across forest communities were driven by different variables: leaf economy was primarily shaped by the proportion of deciduous trees, leaf density by soil available P and temperature, and leaf N:P ratio by temperature. These three leaf trait dimensions together explained 60.2% of the variation in ecosystem-scale forest maximum photosynthesis, with the leaf N:P ratio showing the strongest association, followed by the dimensions of leaf economy and leaf density. Forests with moderate leaf N:P ratios and more acquisitive traits had higher photosynthesis than other forests. Our findings highlight the potential of community canopy leaf traits in predicting biogeographic variation in ecosystem-scale forest functioning.