Previous studies have shown that hemiepiphytic figs have a more plastic nutrient-use strategy, but more conservative water-use strategy and higher drought tolerance than terrestrial figs. However, the dynamic response of leaf traits within the crown, and trait network from epiphytes to free-standing trees remains poorly understood.
In a study published in Tree Physiology, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) and Yunnan University tried to reveal the acclimation of hemiepiphytic and terrestrial figs to different environmental conditions at multiple scales, and their trait co-variation.
The researchers investigated intraspecific variations of 16 leaf functional traits of a common fig species (Ficus tinctoria) in relation to different scales: habitat types (hemiepiphytic and terrestrial), growth stages (small, medium and large) and tree crown positions (upper, middle and lower) in Xishuangbanna, Southwest China.
The results showed that there was significant intraspecific variation in leaf functional traits of F. tinctoria, and hemi-epiphytic F. tinctoria experienced more complex and variable vertical habitats than epiphytic F. tinctoria, which had stronger canopy adaptation characteristics.
Ficus tinctoria shows a high degree of intraspecific variation in leaf area (LA), and some traits including stable nitrogen isotope (δ15N) and LA, which are mainly affected by tree crown position, growth stage and their interaction. The hemiepiphytic and terrestrial figs showed differences in trait differentiation within the crown at different growth stages.Moreover, figs in the hemiepiphytic and terrestrial habitats have developed different strategies to cope with environmental heterogeneity and stresses by co-variation of traits. The intraspecific variation of F. tinctoria at the multi-scale mainly reflects their intraspecific trait plasticity with changes in ontogeny and individual crown position levels.
"Our study showed that multi-scaled intraspecific variation and co-variation in plant functional traits can help plants adapt to complex and variable habitats. Intraspecific variation is important in exploring trait-based plant adaptation strategies,” said SONG Liang of XTBG.

Contact
Song Liang  Ph.D Principal Investigator
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
E-mail: songliang@xtbg.ac.cn