会同杉木器官间C、N、P化学计量比的季节动态与异速生长关系  

Seasonal dynamics and allometric growth relationships of C,N,and P stoichiometry in the organs of Cunninghamia lanceolata from Huitong

作　　者：陈婵[1,2] 王光军[1,2,3] 赵月[1,2] 周国新[1,2] 李栎[1,2] 高吉权 

机构地区：[1]中南林业科技大学,长沙410004 [2]南方林业生态应用技术国家工程实验室,长沙410004 [3]湖南会同杉木林国家重点野外科学观测研究站,会同418307

出　　处：《生态学报》2016年第23期7614-7623,共10页Acta Ecologica Sinica

基　　金：2014年度湖南省高校创新平台开放基金项目(14k115);湖南省研究生科研创新课题项目(CX2013B355);2014湖南省自然科学基金创新研究团体项目

摘　　要：生态化学计量特征能够反映植物器官的内稳性及其相互关系。以湖南会同25年生杉木人工林为研究对象,分析了叶、枝、根的C、N、P及其化学计量季节动态,探讨了养分元素的变异性特征、变异来源,以及元素间的异速生长关系。结果表明:C、N、P含量的年平均值均在叶中表现最大,分别为(527.60±15.07)、(10.55±1.89)、(2.13±0.31)g/kg;而C∶N、C∶P、N∶P的年平均值最大的则是根,分别为(78.12±12.54)、(619.46±48.23)、(7.13±3.57);不同器官的年均C∶N∶P排序为根>枝>叶。叶和根的C、N含量及N∶P、叶和枝的P含量变化趋势均为先升高后降低再升高,叶、根的C∶N值则表现为先降低后升高再降低的变化趋势。叶、枝、根的年平均N∶P比(均小于14)远低于我国年平均水平(16.3);不同器官的C含量变异系数较小,均低于9%,N、P含量及其化学计量比变异系数较大,均高于30%,其中枝叶的P含量和枝的N∶P变异系数分别高达65.04%和62.41%;根据变异来源分析,器官、月份和器官与月份的交互作用对C、N、P含量及其化学计量变异的影响均达到显著水平(P<0.05)。叶、根的C与N具有显著的异速生长关系(N-C^(2.777),P=0.008;N-P^(2.574),P=0.002),叶、枝、根的N、P含量表现出正相关性,异速生长指数分别为0.539、0.617、0.721。研究表明25年生杉木的生长更多的受到N元素的限制,养分利用效率在根中最高;叶、枝、根C-P的异速生长关系证明不同器官对于各自的养分分配是具有相似性的。Organ-specific comparisons of carbon （ C）, nitrogen （ N）, and Phosphorus （P） stoichiometrics and allometrics reflected the interfaces of the functional differentiation of plant tissues and the influence of environmental constraints. Here, we explored the seasonal constraints of organ-specific C, N, and P stoichiometrics and allometrics in a 25-year-old Cunninghamia lanceolata stand in Huitong, which located in subtropical China. Leaves, branches, and roots of trees covering a wide topographical gradient were collected at different seasons （January, April, July, October）. We analyzed the seasonal dynamics of C, N, P content and C ：N ：P ecological stoichiometry in leaf, branch and root, and then revealed the variation,variation sources and allometric relationship of nutrient elements with different organs and months. The results showed that the C, N, and P contents and stoichiometries of the C. lanceolata varied in different organs and changed with seasons, reflecting a plastic seasonal variation and strong ontogenetic self-regulation. In all organs, the annual average N ：P ratios （〈14） were much lower than the average level in China （16.3）, suggesting that the growth of C. lanceolata in this region is relatively limited by N. The maximum C contents were observed in April for all organs, which was likely due to the increment of temperature in the growing season. The maximum C ：N ratios were observed in July in all cases, indicating a relatively higher utilization rate of N in summer. In addition, the coefficients of variation （CVs） for N, P, C ：N, C ：P, and N ：P were all higher than 30%, and the CVs for the P content and the N ：P ratio in the branch were 65.04% and 62.41%, respectively. N and P of leaves, branches, and roots showed a positive correlation and an extremely significant allometric growth relationship between them（P〈0.001 ）, with allometric exponents of 0.539, 0.617, and 0.721, respectively. This result demonstrated that growth rate changes significant

关 键 词：杉木 植物器官 生态化学计量特征 变异系数 异速生长关系 

分 类 号：S791.27[农业科学—林木遗传育种]