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bioRxiv · 10.1101/2021.03.02.433324

Plant hydraulics coordinated with photosynthetic traits and climate

Xu, H.·Wang, H.·Prentice, I. C.·Harrison, S. P.·Wright, I.
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Abstract

The coupling between water loss and carbon dioxide uptake drives the coordination of plant hydraulic and photosynthetic traits. Analysing multi-species measurements on a 3000 m elevation gradient, we found that hydraulic and leaf-economic traits were less plastic, and more closely associated with phylogeny, than photosynthetic traits. The two trait sets are linked by the sapwood-to-leaf area ratio (Huber value, vH), shown here to be codetermined by sapwood hydraulic conductance (KS), leaf mass-per-area (LMA) and photosynthetic capacity (Vcmax). Substantial hydraulic diversity was related to the trade-off between KS and vH. Leaf drought tolerance (inferred from turgor loss point, -{pi}tlp) increased with wood density, but the trade-off between hydraulic efficiency (KS) and -{pi}tlp was weak. The least-cost optimality framework was extended to predict trait (KS-dominated) and environmental (temperature-dominated) effects on vH. These results suggest an approach to include photosynthetic-hydraulic coordination in land-surface models; however, prediction of non-plastic trait distributions remains a challenge.

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Xu, H., Wang, H., Prentice, I. C., Harrison, S. P., Wright, I.. 2021-03-02. Plant hydraulics coordinated with photosynthetic traits and climate. https://doi.org/10.1101/2021.03.02.433324

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