Chin J Plant Ecol ›› 2024, Vol. 48 ›› Issue (6): 719-729.DOI: 10.17521/cjpe.2023.0271  cstr: 32100.14.cjpe.2023.0271

Special Issue: 植物功能性状

• Research Articles • Previous Articles     Next Articles

Traits mediate response of seedling survival rate to neighborhood competition and abiotic environment

WEN Jia, ZHANG Xin-Na, WANG Juan, ZHAO Xiu-Hai, ZHANG Chun-Yu*()   

  1. State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China
  • Received:2023-09-22 Accepted:2024-02-26 Online:2024-06-20 Published:2024-02-26
  • Contact: *ZHANG Chun-Yu(zcy_0520@163.com)
  • Supported by:
    National Key R&D Program of China(2023YFF1304004-06);National Natural Science Foundation of China(32371870)

Abstract:

Aims The trait-based approach has been extensively utilized to evaluate the influence of neighborhood competition on seedling survival. However, previous studies used species average traits, ignoring intraspecific trait variation.

Methods Based on the monitoring of 150 seedling plots in a needleleaf and broadleaf mixed forest in Jiaohe, Jilin, we used a generalized linear mixed effect model of binomial distribution to compare the effects of intraspecific trait variation and species average traits on seedling survival rate, and explore how functional traits mediate seedling responses to neighborhood competition and abiotic environmental factors.

Important findings The intraspecific trait variation model and the species average trait model had inconsistent predictive abilities for seedling survival rate. Specifically, intraspecific variability model of specific leaf area (SLA) exhibited a smaller Akaike information criterion value and Bayesian information criterion value, a larger explanatory variance and a better fit. While species average trait model of leaf area (LA), leaf carbon content (LCC), and leaf nitrogen content (LNC) performed better. In addition, traits mediate the effects of neighborhood competition and soil nutrients on seedling survival. Seedlings with smaller LA have higher survival rates under the same density dependence. Higher LCC increases seedling survival rate in the absence of soil nutrients, while seedling survival rate decreases under fertile soil conditions. The ability of intraspecific trait variation in predicting individual survival of seedlings may not be stronger than species average trait, which may be related to forest stands and environmental factors. In addition, the presence of neighborhood competition and environmental variables can enhance the relationships between traits and seedling survival. Although intraspecific trait variation may not improve the prediction of seedling survival rate, this individual-based approach provides a new perspective for predicting seedling dynamics.

Key words: intraspecific trait variation, negative density dependence, habitat filtering, trait dissimilarity