J Syst Evol

• Research Articles •    

Diversification and phylogenetic correlation of functional traits for co-occurring understory species in the Chinese boreal forest

Bo Liu1, Jin‐Long Zhang2, Matthew K. Lau1, Xu‐Gao Wang1, Yu Liang1,3*, and Tian‐Xiao Ma1   

  1. 1 CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
    2 Flora Conservation Department, Kadoorie Farm & Botanic Garden, Tai Po, New Territories, Hong Kong, SAR, China
    3 Key Laboratory of Terrestrial Ecosystem Carbon Neutrality, Liaoning Province, Shenyang 110016, China

    *Author for correspondence. E‐mail: liangyu@iae.ac.cn
  • Received:2021-04-25 Accepted:2022-02-13 Online:2022-04-11

Abstract:

Functional traits impact species interactions, community composition, and ecosystem functioning. However, few studies have focused on the diversification and phylogenetic correlation of multiple functional traits over geological time. We conducted phylogenetic comparative analysis for boreal forest understory species in northeast China to examine the diversification and phylogenetic correlation in several functional traits: leaf area (LA), leaf carbon content (LCC), leaf dry matter content (LDMC), leaf nitrogen content (LNC), plant height (PH), and specific leaf area (SLA). Phylogenetic signals showed that there were very low levels of phylogenetic niche conservatism (PNC) in understory leaf-related traits and plant height, suggesting divergence of functional traits for the co-occurring understory species. The disparity through time analyses (DTT) indicated that trait disparities mainly originated during recent divergence events and there were no differences in the observed trait disparities compared with that expected under Brownian motion. Furthermore, we found both positive and negative phylogenetic correlations among the measured functional traits. The very low levels of PNC suggest that these functional traits diverged among co-occurring understory species, and that those species are distantly phylogenetically related. The phylogenetic correlations among traits may be caused by both positively and negatively correlated adaptions that correspond to resource acquisition strategies. This study provides evidence that divergence in functional traits may reflect understory adaptions to boreal conditions.

Key words: correlated adaption, divergence, geological time, phylogenetic signal, trade‐off, understory