Response of plant,litter,and soil C:N:P stoichiometry to growth stages in Quercus secondary forests on the Loess Plateau,China  

作　　者：Juanjuan Zhang Xinyang Li Meng Chen Linjia Huang Ming Li Xu Zhang Yang Cao 

机构地区：[1]College of Forestry,Northwest A&F University,Yangling 712100,People’s Republic of China [2]State Key Laboratory of Soil Erosion and Dryland Farming On Loess Plateau,Northwest A&F University,Yangling 712100,Shaanxi,People’s Republic of China [3]Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,Shaanxi,People’s Republic of China

出　　处：《Journal of Forestry Research》2023年第3期595-607,共13页林业研究（英文版）

基　　金：supported by the National Nature Science Foundation of China(No.41977418 and 42130717);National Key R&D Program of China(2016YFC0501703 and 2017YFC0504605);CAS“Light of West China”Program(XAB201702).

摘　　要：Ecological stoichiometry is an important indicator of biogeochemical cycles and nutrient limitations in terrestrial ecosystems.However,little is known about the response of ecological stoichiometry to plant growth.In this study,carbon(C),nitrogen(N),and phosphorus(P)concentrations were evaluated in plant tissues(trees,shrubs,and herbs),litter,and soil of young(≤40-year-old),middle-aged(41–60-year-old),near-mature(61–80-year-old),and mature(81–120-year-old)Quercus secondary forests on the Loess Plateau,China.Vegetation composition,plant biomass,and C stock were determined to illustrate their interaction with stoichiometry.Only tree biomass C signifi cantly increased with stand development.Leaf N and trunk P concentrationsgenerally increased,but branch P decreased with growth stage.Fine roots had the highest C and P concentrations at the middle-aged stage.In contrast,shrubs,herbs,litter,and soil C:N:P stoichiometry did not change signifi cantly during stand development.Leaf N and P were positively correlated with soil C,N,P,and their ratios.However,there was no signifi cant correlation between litter and leaves in terms of C:N:P stoichiometry.A redundancy analysis showed that soil N best explained leaf N and P variance,and tree biomass and C stock were related to biotic factors such as tree age and shrub biomass.Hierarchical partitioning analysis indicated that,compared with soil or litter variables,stand age only accounted for a relatively small proportion of leaf C,N,and P variation.Thus,secondary Quercus ecosystems might have inherent ability to maintain sensitive responses of metabolically active organs to environmental factors during stand aging.The results of this work help to elucidate the biogeochemical cycling of secondary forest ecosystems in tree development,provide novel insights into the adaptation strategies of plants in diff erent organs and growth stages,and could be used to guide fertilization programs and optimize forest structure.

关 键 词：Ecological stoichiometry Tree biomass C stock Understory plant Age Stand development 

分 类 号：S718.5[农业科学—林学]