J Plant Ecol ›› 2022, Vol. 15 ›› Issue (4): 700-710.DOI: 10.1093/jpe/rtab105

• Research Articles • Previous Articles     Next Articles

Coloration and phenology manifest nutrient variability in senesced leaves of 46 temperate deciduous woody species

Xingchang Wang1,2,†, Qi Wang3,†, Yue Chen1,2, Rui Zhao1,2, Jiahui Zhang4, Xiankui Quan1,2, Fan Liu1,2 and Chuankuan Wang1,2, *   

  1. 1 Center for Ecological Research, Northeast Forestry University, Harbin 150040, China, 2 Key Laboratory of Sustainable Forest Ecosystem Management—Ministry of Education, Northeast Forestry University, Harbin 150040, China, 3 National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agroenvironmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Science, Guangzhou 510650, China, 4 Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

    *Corresponding author. E-mail: wangck-cf@nefu.edu.cn
    These authors contributed equally to this work.
  • Received:2020-02-25 Revised:2020-05-25 Accepted:2021-08-29 Online:2021-09-15 Published:2022-08-01

Abstract: Senesced-leaf nutrient concentrations vary significantly among coexisting plant species reflecting different leaf nutrient use strategies. However, interspecific variation in senesced-leaf nutrients and its driving factors are not well understood. Here, we aimed to determine interspecific variation and its driving factors in senesced-leaf nutrients. We explored interspecific variation in carbon (C), nitrogen (N) and phosphorus (P) concentrations in newly fallen leaves of 46 coexisting temperate deciduous woody species across the Maoershan Forest Ecosystem Research Station, Northeast China. The relative importance of 10 biotic factors (i.e. mycorrhiza type, N-fixing type, growth form, shade tolerance, laminar texture, coloring degree, coloring type, peak leaf-coloration date, peak leaf-fall date and end leaf-fall date) was quantified with the random forest model. N and P concentrations varied 4- and 9-fold among species, respectively. The high mean N (15.38 mg g−1) and P (1.24 mg g−1) concentrations suggested a weak N and P limitation in the studied forest. Functional groups had only significant effects on specific nutrients and their ratios. P concentration and N:P were negatively correlated with peak and end leaf-fall dates for the ectomycorrhiza species group. Brighter-colored leaves (red > brown > yellow > yellow-green > green) tended to have lower N and P concentrations and higher C:N and C:P than darker-colored leaves. The random forest model showed that autumn coloration and leaf-fall phenology contributed 80% to the total explanation of nutrient variability among species. The results increase our understanding of the variability in senesced-leaf nutrients as a strategy of woody plant nutrition in temperate forests.

Key words: leaf coloring, autumn phenology, leaf litter, stoichiometry, functional groups

摘要:
颜色和物候表明46种温带落叶木本植物衰老叶片的养分变异
不同共生植物的叶片养分含量差异显著,反映了不同的叶片养分利用策略。然而,衰老叶片养分的种间变异及其驱动因素尚不清楚。本研究旨在探讨衰老叶片养分的种间变异及其驱动因素。我们在中国东北的帽儿山森林生态系统研究站测定了46种共存温带落叶木本植物新鲜落叶的碳、氮、磷浓度。 采用随机森林模型量化10个生物因素(菌根类型、固氮类型、生长形态、耐阴性、叶片质地、变色程度、变色类型、叶片变色峰期、落叶峰期和落叶末期)的相对重要性。研究结果表明,落叶氮浓度种间变化为4倍,磷浓度变化达9倍。较高的氮和磷平均浓度(15.38和1.24 mg g−1)表明该森林氮和磷限制较弱。功能群仅对特定养分及其比值有显著影响。磷浓度、氮磷比与外生菌根树种的落叶高峰日和落叶结束日呈负相关。颜色鲜艳的叶片(红色>棕色>黄色>黄绿色>绿色)倾向于比绿色叶片氮和磷浓度更低而碳氮比和碳磷比较高。随机森林模型表明,秋季叶变色和落叶物候贡献了80%的种间变异解释量。这些结果增加了我们对温带森林木本植物营养策略之衰老叶片养分变异性的理解。

关键词: 叶变色, 秋季物候, 凋落叶, 化学计量, 功能群