Linking nutrient resorption stoichiometry with plant growth under long-term nitrogen addition  

作　　者：Aijun Xing Haihua Shen Longchao Xu Mengying Zhao Zhengbing Yan Jingyun Fang 

机构地区：[1]State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,Beijing,100093,China [2]University of Chinese Academy of Sciences,Beijing,100049,China [3]Institute of Ecology,College of Urban and Environmental Sciences,and Key Laboratory for Earth Surface Processes of the Ministry of Education,Peking University,Beijing,100871,China [4]College of Ecology,Taiyuan University of Technology,Shanxi,030024,China

出　　处：《Forest Ecosystems》2024年第5期642-649,共8页森林生态系统（英文版）

基　　金：supported by National Natural Science Foundation of China(Nos.31988102,32301390);Key Research Program of Frontier Sciences,CAS(No.QYZDY-SSW-SMC011);China Postdoctoral Science Foundation(No.2022T150697);supported by the postdoctoral fellowship program of CPSF under grant number GZC20240856.

摘　　要：Increased nitrogen(N)input can potentially lead to secondary phosphorus(P)limitation;however,it remains unclear whether differences in the plant's ability to cope with this P deficiency are related to their growth responses.Using a long-term experiment of N addition in a boreal forest,we explored the potential role of plant nutrient resorption efficiency and its stoichiometry in mediating plant growth responses to increased N input.We recorded the cover and measured the concentration and resorption efficiency of leaf N and P as well as the photosynthesis of a grass Deyeuxia angustifolia and a shrub Vaccinium vitis-idaea.The cover of the grass D.angustifolia increased with increasing N addition,while that of the shrub V.vitis-idaea decreased with N addition rate and almost disappeared from the high-level N addition over time.P resorption efficiency(PRE)increased in D.angustifolia but decreased in V.vitis-idaea with increasing leaf N:P which was increased by N addition for both species.In addition,photosynthesis increased linearly with N resorption efficiency(NRE)and PRE but was better explained by NRE:PRE,changing nonlinearly with the ratio in a hump-shaped trend.Furthermore,the variance(CV)of NRE:PRE for V.vitis-idaea(123%)was considerably higher than that for D.angustifolia(29%),indicating a more stable nutrient resorption stoichiometry of the grass.Taken together,these results highlight that efficient P acquisition and use strategy through nutrient resorption processes could be a pivotal underlying mechanism driving plant growth and community composition shifts under N enrichment.

关 键 词：Nitrogen deposition Understory layer Community shift Nutrient limitation Phosphorus resorption efficiency Stoichiometric homeostasis 

分 类 号：S718.5[农业科学—林学]