川西高山林线交错带凋落叶分解速率与初始质量的关系  

Relationships between decomposition rate of leaf litter and initial quality across the alpine timberline ecotone in Western Sichuan,China

作　　者：杨林[1] 邓长春[1] 陈亚梅[1] 和润莲 张健[1] 刘洋[1] 

机构地区：[1]四川农业大学生态林业研究所/四川省生态林业工程重点实验室/高山森林生态系统定位研究站/长江上游生态安全协同创新中心,成都611130

出　　处：《应用生态学报》2015年第12期3602-3610,共9页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31200345;31570605);教育部高等学校博士学科点科研基金项目(20115103120003);国家"十二五"科技支撑计划项目(2011BAC09B05)资助

摘　　要：对我国川西高山林线交错带14种代表性植物凋落叶分解速率与初始质量的关系进行研究.结果表明：高山林线交错带植物凋落叶分解速率（k）为0.16-1.70,乔木和苔藓凋落叶分解较慢,灌木凋落叶次之革本凋落叶分解最快.凋落叶分解速率与N、木质素、酚类物质、C/N、C/P、木质素/N均具有显著的线性回归关系.通径分析得出,木质素/N和半纤维素含量可以解释k变异的78.4%,其中木质素/N可以解释k变异的69.5%,木质素/N对κ的直接通-径系数为-0.913.主成分分析表明,第1排序轴k、分解时间（t）的贡献率达99.2%,木质素/N、木质素含量、C/N、C/P与第1排序轴呈显著正相关,其中木质素/N与第1排序轴的相关关系最强（r=0.923）.木质素/N是影响川西高山林线交错带植物凋落叶分解速率的关键质量指标且凋落叶初始木质素/N越高分解速率越低.The relationships between litter decomposition rate and their initial quality of 14 representative plants in the alpine forest ecotone of western Sichuan were investigated in this paper.The decomposition rate k of the litter ranged from 0.16 to 1.70.Woody leaf litter and moss litter decomposed much slower,and shrubby litter decomposed a little faster.Then,herbaceous litters decomposed fastest among all plant forms.There were significant linear regression relationships between the litter decomposition rate and the N content,lignin content,phenolics content,C/N,C/P and lignin/N.Lignin/N and hemicellulose content could explain 78.4%variation of the litter decomposition rate（k） by path analysis.The lignin/N could explain 69.5%variation of k alone,and the direct path coefficient of lignin/N on k was-0.913.Principal component analysis（PCA） showed that the contribution rate of the first sort axis to k and the decomposition time（t） reached 99.2%.Significant positive correlations existed between lignin/N,lignin content,C/N,C/P and the first sort axis,and the closest relationship existed between lignin/N and the first sort axis（r = 0.923）.Lignin/N was the key quality factor affecting plant litter decomposition rate across the alpine timberline ecotone,with the higher the initial lignin/N,the lower the decomposition rate of leaf litter.

关 键 词：高山林线交错带 分解速率 凋落叶 初始质量 木质素/N 

分 类 号：S714[农业科学—林学]