Plant Diversity ›› 2022, Vol. 44 ›› Issue (02): 163-169.DOI: 10.1016/j.pld.2021.06.002

• Articles • Previous Articles    

Intraspecific trait variation of woody species reduced in a savanna community, southwest China

Lubing Liua,b, Jie Yanga, Min Caoa, Qinghai Songa   

  1. a CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Yunnan 666303, China;
    b University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2021-01-29 Revised:2021-05-28 Published:2022-04-24
  • Contact: Min Cao,E-mail:caom@xtbg.ac.cn
  • Supported by:
    This research was supported by the National Natural Science Foundation of China (31870410 and Dimensions US-China: 32061123003), the Chinese Academy of Sciences Youth Innovation Promotion Association, the West Light Foundation of the Chinese Academy of Sciences and the Ten Thousand Talents Program of Yunnan (YNWR-QNBJ-2018-309). We thank all the staff of Yuanjiang Savanna Ecological Station (YSES), for their dedication and assistance in the performance of field work. We are grateful to Public Technology Service Center XTBG, for providing professional analysis of our specimens. Thanks are also due to Global Change Group for setting up the eddy covariance system in 1-ha monitoring plot at YSES, from which we obtained environmental data.

Abstract: Plants deploy various ecological strategies in response to environmental heterogeneity. In many forest ecosystems, plants have been reported to have notable inter- and intra-specific trait variation, as well as clear phylogenetic signals, indicating that these species possess a degree of phenotypic plasticity to cope with habitat variation in the community. Savanna communities, however, grow in an open canopy structure and exhibit little species diversification, likely as a result of strong environmental stress. In this study, we hypothesized that the phylogenetic signals of savanna species would be weak, the intraspecific trait variation (ITV) would be low, and the contribution of intraspecific variation to total trait variance would be reduced, owing to low species richness, multiple stresses and relatively homogenous community structure. To test these hypotheses, we sampled dominant woody species in a dry-hot savanna in southwestern China, focusing on leaf traits related to adaptability of plants to harsh conditions (year-round intense radiation, low soil fertility and seasonal droughts). We found weak phylogenetic signals in leaf traits and low ITV (at both individual and canopy-layer levels). Intraspecific variation (including leaf-, layer- and individual-scales) contributed little to the total trait variance, whereas interspecific variation and variation in leaf phenology explained substantial variance. Our study suggests that intraspecific trait variation is reduced in savanna community. Furthermore, our findings indicate that classifying species by leaf phenology may help better understand how species coexist under similar habitats with strong stresses.

Key words: Phylogenetic signal, Savanna, Intraspecific trait variation (ITV), Leaf phenology, Coexistence