华北落叶松针叶碳、氮、磷含量及化学计量比的季节变化  

Seasonal variations of leaf C,N,P contents and stoichiometry of Larix principis-rupprechtii

作　　者：赵亚芳[1,2] 徐福利[1,3] 王渭玲[3] 王国兴[3] 陈钦程 赵海燕[3] 马亚娟[3] 

机构地区：[1]中国科学院水利部水土保持研究所,陕西杨凌712100 [2]中国科学院大学,北京100049 [3]西北农林科技大学,陕西杨凌712100

出　　处：《植物营养与肥料学报》2015年第5期1328-1335,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家重点基础研究发展计划(973计划)项目(2012CB416902)资助

摘　　要：【目的】碳(C)、氮(N)和磷(P)在林木的生长发育中有着重要作用,三者的含量变化和元素比值控制着林木的营养和生长状况。本研究主要分析了秦岭山区同一树种不同林龄叶片的C、N、P含量及化学计量比随季节变化的规律,为林木施肥管理提供依据。【方法】在林木生长季的不同月份(2012年5月到10月每月中旬),对秦岭5年生(5a)、10年生(10 a)、20年生(20 a)3种林龄的华北落叶松针叶进行定期采集,并测定不同月份各林龄针叶的C、N、P含量和化学计量比值,对不同林龄不同生长季华北落叶松针叶的C、N、P及C∶N、C∶P、N∶P的动态变化进行分析,并对其C∶N与氮含量、C∶P与磷含量进行相关性分析。【结果】1)3种林龄针叶的碳含量从生长初期(5 6月)到生长旺盛期(7 8月)逐渐增加,生长末期(8 9月)逐渐降低,但到落叶期(10月)又小幅回升。2)3种林龄华北落叶松针叶的氮含量在整个生长季内(5 10月)均呈现先降低后升高再降低的趋势,各林龄针叶氮含量升高和降低的时间存在差异,5 a和20 a林龄的针叶N含量从6月到生长旺盛期(7月、8月)基本上保持上升趋势,而10 a林龄针叶的氮含量6 7月份先逐渐降低,7 9月份急剧升高,落叶前期到落叶(9 10月)这段时间3种林龄针叶的N含量均急剧下降为最低值。3)3种林龄针叶磷含量在整个生长季节内的变化趋势基本一致,均先降低后升高再降低最终维持稳定。4)5 a、10 a和20 a林龄的华北落叶松在生长季节内针叶的C∶N变化范围分别为21.83 56.42、18.4358.49和22.54 87.83,变异系数分别达到了37.74%、42.05%和68.42%,随着树龄的增长其变异系数逐渐增大。5)5 a、10 a、20 a林龄的华北落叶松在生长季节内针叶C∶P的变化范围分别为169.17 402.85、180.54 395.01和213.02 398.75,变异系数依次为31.35%、31.43%和22.88%。6)针叶的N∶P,5 a、10 a、20 a在生长季节内的变化范围分别为6.77 15.42�[Objectives]Carbon （C）, nitrogen （N） and phosphorus （P） play an important role in forests growth. The contents and ratios of C, N and P element reflect the nutritional status and healthy growth of forests. The＆amp;nbsp;objective of this research was to explore the seasonal variations of C, N, P contents in the leaves in different ages, so to provide a basis for the academic mamgement of the artificial forests. [Methods]Three different ages, namely 5 years old （5 a） , 10 years old （10 a） and 20 years old （20 a） of Larix principis-rupprechtii in Qinling Mountains were chosen as experimental materials. Leaf samples were collected in different growth phases in the middle of a month from May to October in 2012. The C, N, P contents and stoichiometry were monitored. Seasonal dynamics of leaf C, N, P contents and C ∶N, C ∶P, N ∶P mass ratios in different ages of Larix principis-rupprechtii were analyzed. Data were also analyzed by correlation analysis between N content and C ∶N and P content and C ∶P .[Results] 1 ） C content of these three ages increased gradually from growth stage （ May to June ） to the vigorous growth period （ July to August） ,then decreased at growth anaphase （ August to September） , but there had been a slight pick-up in the defoliation （October）. 2） The N content of three ages increased first, then decreased and went up again throughout the growing season （ May to October） . The increasing or reducing time among three ages was different. 5 a and 20 a maintained the upward trend basically from June to vigorous growth period, while the N content of 10 a decreased first from June to July, and then increased sharply from July to September. The N content of three ages decreased sharply to the lowest value from early defoliation to defoliation. 3） The P content of three ages kept the same trend throughout the growing season. They all decreased first, then increased and decreased again, finally they kept stable. 4） Seasonal dynamics of leaf C

关 键 词：华北落叶松 林龄 碳 氮 磷 季节动态 

分 类 号：S791.22[农业科学—林木遗传育种] S718.5[农业科学—林学]