四川农业大学学报2025，Vol.43Issue(4)：922-932,11.DOI:10.16036/j.issn.1000-2650.202503587
氮添加对华西雨屏区峨眉含笑不同器官化学计量特征影响
Effects of Nitrogen Addition on Stoichiometric Characteristics of Different Organs of Michelia wilsonii in Rain Screen Area of West China
摘要
Abstract
[Objective]This study investigated the stoichiometric responses of the dominant tree species Michelia wilsonii in Lingyan Mountain to long-term nitrogen(N)addition,aiming to clarify its survival strategies under elevated nitrogen concentrations.[Method]Using M.wilsonii from secondary forests in Lingyan Mountain,Dujiangyan,China,we analyzed the stoichiometric characteristics of carbon(C),nitro-gen(N),and phosphorus(P)in different plant organs(green leaves,litter leaves,branches,coarse roots,fine roots,and trunks)of M.wilsonii under different simulated N deposition treatments(control,CK;low nitrogen,LN,20 kg/(hm2·a);and high nitrogen,HN,40 kg/(hm2·a).[Result]① N addition signifi-cantly influenced organ-level stoichiometric characteristics of M.wilsonii organs.With increasing N addi-tion,N concentrations in litter leaf and trunks initially decreased and then increased,while those in green leaves,branches,coarse roots,and fine roots showed the opposite tread.The concentrations of both N and P varied consistently across green leaves,litter leaves,fine roots and trunks;P increased in branches but fell declined in coarse roots.② Organ nutrient concentrations varied markedly under the same treatments;trunks exhibited the lowest levels of both N and P,while fine roots had the highest levels.③ N addition soil depth,and their interaction significantly affected soil organic carbon(SOC),total nitro-gen(TN),and total phosphorus(TP).Under CK and LN treatments,SOC and TN first decreased and then increased with depth,whereas both declined continuously under HN.Additionally,HN treatment notably reduced topsoil pH.④ Correlations between stoichiometric characteristics and soil chemical prop-erties differed among plant organ types:root stoichiometry was most closely associated with soil properties,followed by trunks and branches,while leaves showed the weakest associations.[Conclusion]Nitrogen addition altered nutrient allocation strategies within M.wilsonii organs.Compared with green leaves,the species tended to contribute more nutrients to fine roots under nitrogen addition conditions,while branches retained a storage function.The elemental concentration within roots,trunks,and branches may provide more reliable indicators of soil nutrient availability than leaf chemistry.关键词
模拟氮沉降/植物器官/化学计量特征/土壤化学性状Key words
simulated nitrogen deposition/plant organs/stoichiometric characteristics/soil chemical properties分类
农业科技引用本文复制引用
郑小英,常文正,宋秋,肖雨希,徐红伟,游成铭,刘思凝..氮添加对华西雨屏区峨眉含笑不同器官化学计量特征影响[J].四川农业大学学报,2025,43(4):922-932,11.基金项目
国家自然科学基金(32001165) （32001165）
四川省自然科学基金(2025ZNSFSC0267) （2025ZNSFSC0267）
中国博士后科学基金会(2022M722297). （2022M722297）
