中国南方灌丛优势木本植物叶的氮、磷含量及其影响因素  

Leaf nitrogen and phosphorus concentration and the empirical regulations in dominant woody plants of shrublands across southern China

作　　者：李家湘[1,2] 徐文婷[1] 熊高明[1] 王杨[1] 赵常明[1] 卢志军[3] 李跃林[4] 谢宗强[1] 

机构地区：[1]中国科学院植物研究所植被与环境变化国家重点实验室,北京100093 [2]中南林业科技大学林学院,长沙410004 [3]中国科学院武汉植物园水生植物与流域生态院重点实验室,武汉430074 [4]中国科学院华南植物园,广州510650

出　　处：《植物生态学报》2017年第1期31-42,共12页Chinese Journal of Plant Ecology

基　　金：中国科学院战略性先导科技专项(XDA05050302)

摘　　要：探索植物器官中氮(N)、磷(P)含量沿环境梯度的分异规律,有助于揭示陆地生态系统物质循环和植物养分适应策略的过程和机制。该文采用分层随机抽样法,在中国南方12个省市区布设462个灌丛样点,对其中193种优势木本植物叶N、P含量进行调查取样。结果表明:1)南方灌丛优势木本植物叶的N、P含量几何均值分别为16.57 mg·g^(–1)和1.02 mg·g^(–1);其中,落叶木本植物(17.91 mg·g^(–1)、1.14 mg·g^(–1))显著高于常绿木本植物(15.19 mg·g^(–1)、0.89 mg·g^(–1));叶P含量较N含量具有更大的变异性和环境依赖性。2)随年平均气温(MAT)的升高,常绿木本植物叶N、P含量降低,落叶木本植物叶N、P含量呈逐渐增加的趋势;随年降水量(MAP)的增加,常绿木本植物叶N含量降低,落叶木本植物叶N含量增加,两者P含量下降。3)土壤N含量的增加对两者叶的N含量无显著影响;但随土壤P含量的增加,常绿和落叶木本植物叶P含量均显著增加。4)广义线性回归显示,植物生活型分别可解释叶N、P变异的7.6%和14.4%,MAP和土壤P含量分别解释了0.8%和16.4%的叶P变异。结果表明,中国南方灌丛中优势植物叶的N含量主要受不同生活型植物生长需求所决定,而P含量则受气候、土壤和植物生活型共同决定。Aims Understanding the changes in N and P concentration in plant organs along the environmental gradients can provide meaningful information to reveal the underline mechanisms for the geochemical cycles and adaptation strategies of plants to the changing environment. In this paper, we aimed to answer： （1） How did the N and P concentration in leaves of evergreen and deciduous woody plants change along the environmental gradients？ （2） What were the main factors regulating the N and P concentration in leaves of woody plants in the shrublands across southern China？ Methods Using a stratified random sampling method, we sampled 193 dominant woody plants in 462 sites of 12 provinces in southern China. Leaf samples of dominant woody plants, including 91 evergreen and 102 deciduous shrubs, and soil samples at each site were collected. N and P concentration of the leaves and soils were measured after lapping and sieving. Kruskal-Wallis and Nemenyi tests were applied to quantify the difference among the organs and life-forms. For each life-form, the binary linear regression was used to estimate the relationships between leaf log [N] and log [P] concentration and mean annual air temperature （MAT）, mean annual precipitation （MAP） and log soil total [N], [P]. The effects of climate, soil and plant life-form on leaf chemical traits were modeled through the general linear models （GLMs） and F-tests. Important findings 1） The geometric means of leaf N and P concentrations of the dominant woody plants were 16.57 mg·g^–1 and 1.02 mg·g^–1, respectively. The N and P concentration in leaves （17.91 mg·g^–1, 1.14 mg·g^–1） of deciduous woody plants was higher than those of evergreen woody plants （15.19 mg·g^–1, 0.89 mg·g^–1）. The dependent of leaf P concentration on environmental （climate and soil） appeared more variable than N concentration. 2） Leaf N and P in evergreen woody plants decreased with MAT and but increased with MAP, whereas those in deciduous woody plants showed o

关 键 词：热带亚热带 植物功能性状 植物生活型 生态化学计量 

分 类 号：Q948[生物学—植物学]