image: A and B, hypervolumes constructed from the first three PCA axes from all five traits (leaf area, specific leaf area, carbon content, nitrogen content, and phosphorous content). Each small individual solid dot represents one functional trait space of the altitude, and the mean values of each altitude are indicated by large solid dots. Regression lines are shown for each mountain. C, predicted means and standard errors based on linear mixed models. Different colors indicate three different mountains. Green represents Xishuangbanna, orange represents Ailaoshan and blue represents Lijiang. MAT means mean annual temperature. view more
Credit: ©Science China Press
The study is led by Prof. Keping Ma (Institute of Botany, Chinese Academy of Sciences) who is an expert in biodiversity science. This study is inspired by and conducted in species-rich mountainous areas in Yunnan Province, South-west China.
Variation of functional trait structure across different ecosystems is a key topic in trait-based ecology. Numerous methods have tried to capture the full picture of functional trait structure and hypervolume is one of the best to describe multidimensional trait space. Accordingly, Xiaojuan Liu and Lan Zhang decided to use this method to detect trait structure change of plant communities along altitudinal gradient as a refence of climatic conditions change.
Functional traits of 1590 tree individuals from 48 20 m × 20 m plots across 12 altitudes ranging from 800 m to 3,800 m across three mountains in Yunnan, China were measured, including leaf area, specific leaf area, leaf carbon, nitrogen, and phosphorous content. Hypervolume of plant community from each altitude was constructed using the PCA values from all five traits to describe the functional trait space. Hypervolume overlap was then calculated between volumes of exclusion of one species and full species set to quantify species trait redundancy per plant community.
The team found that the functional trait space (hypervolume) significantly increased with mean annual temperature toward lower altitudes within and across three mountains, whereas species trait redundancy (hypervolume overlap) had different patterns between mountains. This suggests warming can widen functional trait space and alter the redundancy in plant communities. The inconsistent patterns of redundancy between mountains suggest that warming exerts varying influences on different ecosystems. The team finally addressed that identification of climate-vulnerable ecosystems is important in the face of global warming.
Find the article:
Functional trait space and redundancy of plant communities decrease toward cold temperature at high altitudes in Southwest China
https://doi.org/10.1007/s11427-021-2135-3