神农架常绿落叶阔叶混交林碳氮磷化学计量比  

C,N and P stoichiometric ratios in mixed evergreen and deciduous broadleaved forests in Shennongjia, China

作　　者：刘璐 葛结林[1] 舒化伟 赵常明[1] 徐文婷[1] 申国珍[1] 谢宗强[1,2] LIU Lu;GE Jie-Lin;SHU Hua-Wei;ZHAO Chang-Ming;XU Wen-Ting;SHEN Guo-Zhen;XIE Zong-Qiang(State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China;University of Chinese Academy of Sciences,Beijing 100049,China;State-owned Longmenhe Forest Farm,Xingshan,Hubei 443700,China)

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]中国科学院大学,北京100049 [3]湖北省兴山县国有龙门河林场,湖北兴山443700

出　　处：《植物生态学报》2019年第6期482-489,共8页Chinese Journal of Plant Ecology

基　　金：中国科学院前沿科学重点研究项目(QYZDY-SSW-SMC011)~~

摘　　要：生态化学计量学是研究生态过程中化学元素平衡的科学,碳(C)、氮(N)、磷(P)化学计量比是生态系统过程及其功能的重要特征。该研究测定了神农架常绿落叶阔叶混交林植物器官、凋落物及土壤的C、N、P含量,利用生物量加权法计算其化学计量比,并分析该生态系统不同组分间及不同器官间化学计量比的差异。研究结果发现:在不同组分之间,C含量、C:N及C:P表现为植物>凋落物>土壤;N、P含量及N:P表现为凋落物>植物>土壤。在不同植物器官间, C含量的差异较小,其变异系数相对N、P含量较低且保持稳定;N、P含量为叶片最高且变异系数最低;N:P为树皮最高,而枝的变异系数最低。常绿与落叶树种的叶片N、P含量差异显著。与不同森林类型的化学计量比相比,该常绿落叶阔叶混交林植物群落的C:P及N:P较低,凋落物的C:P及N:P较高,土壤的C、N、P化学计量比与亚热带常绿阔叶林基本一致,生态系统的C:N相对较低。利用生物量加权法计算得到的该森林生态系统不同组分的C、N、P化学计量比的大小关系与前人利用枝叶取样算术平均的结果存在较大差异。C、N、P含量及其化学计量比在不同器官的分配及内稳性与器官的生理功能关系密切。Aims Ecological stoichiometry focuses on the balance of chemical elements in ecological processes, in which the stoichiometric ratios of carbon(C), nitrogen(N) and phosphorus(P) are important features of ecological functions. The objectives of this study were to determine the stoichiometric characteristics in different organs and components of mixed evergreen and deciduous broadleaved forests, and to examine the discrepancy in stoichiometric ratios among different components of the ecosystem and plant organs. Methods We measured the concentrations of C, N and P in different plant organs, litter and soil in a mixed evergreen and deciduous broadleaved forest in Shennongjia of Hubei Province, China, and computed the stoichiometric ratios using the biomass-weighted mean method. Important findings The C concentration, C:N and C:P of different components were ranked in the order of plant community > litter > soil, and concentrations of N and P and N:P in the order of litter > plant community > soil. There were little differences in C concentration among various organs, with the coefficient of variation(CV) much lower and less variable than that for N and P concentrations. Both N and P concentrations were highest in leaves with the lowest CV value;N:P was highest in the bark, but with the lowest CV value in branches. Additionally, there were considerable differences in N and P concentrations in leaves between evergreen and deciduous species. Compared with other forest types, this forest had lower C:P and N:P ratios in plant community, higher C:P and N:P ratios in litter, and the C, N and P stoichiometric ratios in soils were consistent with, and the C:N ratio in ecosystem was lower than, that in subtropical evergreen broadleaved forests. Our findings demonstrated the patterns of differences among components in stoichiometry using the integral biomass-weighted mean method differ from that using the arithmetic mean method in selective organs. Furthermore, the distribution and homeostasis of C, N and P concentrations and t

关 键 词：生物量加权法 器官 植物群落 生态系统 内稳态 

分 类 号：G63[文化科学—教育学]