J Plant Ecol ›› 2023, Vol. 16 ›› Issue (2): rtac030.DOI: 10.1093/jpe/rtac030

• Research Articles •     Next Articles

Leaf traits of Chinese fir (Cunninghamia lanceolata) do not support the well-accepted ‘flux trait network' hypothesis

Xi Peng1,2,3, Meifang Zhao1,2,3,*, Shuguang Liu1,2,3,*, Wende Yan1,2,3   

  1. 1College of Life Science and Technology, Central South University of Forestry and Technology, Changsha 410004, China;
    2HuitongNational Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province, Huitong 410015, China;
    3National Engineering Laboratory for Applied Technology of Forestry and Ecology in Southern China, Changsha 410004, China

杉木叶片性状不支持广为接受的通量性状网络假说

Abstract: Widely accepted universal models and hypotheses such as ‘high vein density-faster growth and higher productivity' hold that high leaf vein density may promote higher coupling efficiency of carbon and water, indicating that rapid individual growth and high stand productivity, have attracted huge interest. However, these models and hypotheses do not include enough gymnosperm samples, especially conifers cultivated in subtropics. We here examined the values and scaling relationships between leaf vein density and leaf functional traits sampled from center region of the distribution range of Cunninghamia lanceolate, which has been well known for rapid growth. We also retrieved an empirical dataset that included photosynthetic, biochemical, anatomical and hydraulic traits of Cunninghamia lanceolata. The leaf vein density (ranging from 0.34 to 1.09 mm mm-2) is extremely low compared to the reported global range (1 to 25 mm mm-2), whereas C. lanceolata is famous for both fast-growing and high-yielding in China for a long time. We further verified that higher vein densities were associated with smaller leaves (r = -0.71, P < 0.001), which is consistent with that found in angiosperms. However, we found that vein density-thickness correlations and leaf lifespan plasticity showed opposite trends for C. lanceolate (negative) when compared with global species (positive), and such relationships may indicate the tradeoffs between functional efficiency and productivities. Our results provide an effective complementary assessment of general growth rules, including evaluation of the influence of regional plant trait characterization, configuration of plant species, and traits efficiency for hydraulic potential.

Key words: leaf vein density, leaf size, leaf thickness, trait plasticity, intra-specific variation

摘要:
“高叶脉密度-更快生长和更高的生产力”模型和假说认为高叶脉密度能促进更高的碳和水的耦合效率,暗示了个体的快速生长和高林分生产力,这些假说被研究者广泛关注和认同。然而,这些模型和假说并没有包括足够的裸子植物样本,特别是在亚热带栽培的针叶树种。我们在此研究了叶脉密度和叶功能性状的值和比例关系,这些样本来自于以快速生长著称的杉木(Cunninghamialanceolata)的主要分布区。我们还检索了一个经验数据集,该数据集包括杉木的光合作用、生物化学、解剖学和水力特性。 杉木叶脉密度(范围为0.34-1.09 mm/mm) 远低于全球报道的范围(1-25 mm/mm),而杉木以快速生长和高产在中国长期闻名。我们进一步证实,较高的脉络密度与较小的叶片负相关(r = –0.71,P < 0.001),这与被子植物中发现的情况一致。然而,我们发现,与全球物种(正相关)相比,杉木的叶脉密度-叶厚相关性和叶片寿命可塑性呈现相反的趋势,这种关系可能暗示功能效率和生产力间的权衡。我们的结果将为普适的生长规律提供有效的补充评估,包括评价区域植物性状特征、植物物种的配置和性状效率对水力潜能的影响。

关键词: 叶脉密度, 叶片大小, 叶片厚度, 性状可塑性, 种类变异