Variation in leaf anatomical traits from tropical to cold-temperate forests and linkage to ecosystem functions

Leaf anatomical traits may reflect plants adaption to environmental changes and influence ecosystem functions, as they regulate light absorption and gas exchange to some extent. Here, we hypothesized that leaf anatomical traits were closely related to gross primary productivity (GPP) because photosynthesis commonly occurs in the chloroplasts of palisade and spongy tissues in leaf. Eight leaf anatomical traits were measured in 916 plant species inhabiting from tropical to cold-temperate forests in eastern China: adaxial epidermis thickness (AD), abaxial epidermis thickness (AB), leaf thickness (LT), palisade tissue thickness (PT), and spongy tissue thickness (ST), palisade-spongy tissue ratio (PT/ST), palisade tissue-leaf thickness ratio (PT/LT), and spongy tissue-leaf thickness ratio (ST/LT). Leaf anatomical traits showed significant latitudinal patterns at species, plant functional group (PFG), and community levels (p<.05), and they differed between PFG and community. Temperature and precipitation were the main factors influencing AD, AB, PT/ST, and PT/LT, explaining 33-72% of the total variation at large scale. Furthermore, AB, LT, PT/ST, and PT/LT were significantly correlated with the aridity index. Our findings filled the data gap of plant anatomical traits at regional scales, and broadened current knowledge on the adaptation strategies of plant anatomical traits, which also provided new evidence for linkages of plant traits and functioning across natural communities. A is available for this article.