Understanding the stoichiometric traits of plants is critical for studying their ecological adaptation strategies. Facultative epiphytes (which can also live on the ground) are an important component of epiphytic flora of montane forest ecosystems. However, it remains unclear how facultative epiphytes can adapt different nutritional conditions of ground and canopy habitats.
In a study published in FORESTS, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) systematically elucidated the nutrient use and ecological adaptation strategies of facultative epiphytes from the perspective of stoichiometry using field investigation and greenhouse cultivation experiments.
The researchers studied the ecological stoichiometric characteristics and homeostasis of C, N, and P in three common vascular facultative epiphytes in the montane moist evergreen broad-leaved forest of Ailao Mountain National Nature Reserve.
They showed that epiphytic individuals of facultative epiphytes survive intermittent habitat via luxury consumption of nutrients, while terrestrial individuals use more conservative nutrients.
Moreover, the nutrient use strategies of facultative epiphytes were flexible, which enabled facultative epiphytes to exploit bark and soil interchangeably. Facultative epiphytes had strong control over N and P concentrations and N:P ratio of leaves and stems, while roots had weaker stoichiometric stability.
“These findings suggested that to adapt to the variable habitats in montane forest ecosystem, facultative epiphytes maintain stable metabolic activities of leaves by regulating the absorption and composition of elements in roots,” said Prof. LIU Wenyao of XTBG.
LIU Wenyao Ph.D
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
The pictures of investigated species. (A,B) epiphytic and terrestrial individuals of Cautleya gracilis, (C,D) epiphytic and terrestrial individuals of Elatostema monandrum