Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest  

作　　者：Jiajia Zeng Fan Liu Yuan Zhu Jiayi Li Ying Ruan Xiankui Quan Chuankuan Wang Xingchang Wang 

机构地区：[1]Aulin College,Northeast Forestry University,Harbin 150040,People’s Republic of China [2]Center for Ecological Research,Northeast Forestry University,Harbin 150040,People’s Republic of China [3]Key Laboratory of Agricultural Water Resources,Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Shijiazhuang 050021,People’s Republic of China [4]Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,People’s Republic of China [5]Key Laboratory of Sustainable Forest Ecosystem Management,Ministry of Education,Northeast Forestry University,Harbin 150040,People’s Republic of China

出　　处：《Journal of Forestry Research》2024年第4期60-72,共13页林业研究（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(32171765).

摘　　要：Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf traits.However,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly quantified.In this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous forest.The role of shade tolerance in shaping the seasonal variation and vertical differentiation was examined.During the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance increased.Chlorophyll a:b ratios gradually decreased with increasing shade tolerance.Leaf N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf senescence.Over the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade tolerance.However,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the lower.Seasonal variations in N:P ratios suggest changes in N or P limitation.These findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关 键 词：Leaf traits Leaf nutrients Seasonal variations CHLOROPHYLL Nitrogen Phosphorus Shade tolerance Canopy layers 

分 类 号：S718.5[农业科学—林学]