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bioRxiv · 10.1101/2021.11.30.470674

Contrasting adaptation and optimization of stomatal traits across communities at continental-scale

Liu, C.·Sack, L.·Li, Y.·He, N.
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Abstract

The maximum stomatal conductance (g), a major anatomical constraint on plant productivity, is a function of the stomatal area fraction (f) and stomatal space-use efficiency (e). However, f and g have been considered as equivalents, with e rarely considered, and their adaptation to the environment and their regulation of ecosystem productivity are unclear. Here, we analyzed the community-weighted mean, variance, skewness, and kurtosis of stomatal traits from tropical to cold-temperature forests. The variance of g and f was higher for arid sites, indicating greater functional niche differentiation, whereas that for e was lower, indicating convergence in efficiency. Besides, when other stomatal trait distributions remained unchanged, increasing kurtosis but decreasing skewness of g would improve ecosystem productivity, and f showed the opposite patterns. These findings highlight how the relative importance and equivalence of inter-related traits can differ at community scale.

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Liu, C., Sack, L., Li, Y., He, N.. 2021-12-01. Contrasting adaptation and optimization of stomatal traits across communities at continental-scale. https://doi.org/10.1101/2021.11.30.470674

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