生态学报2018，Vol.38Issue(9)：3078-3085,8.DOI:10.5846/stxb201703180461
四川盆地亚热带常绿阔叶林凋落叶多酚类物质在不同降雨期间的降解特征
The polyphenol degradation characteristics of leaf litter at different rainy stages in a subtropical evergreen broad-leaved forest in the Sichuan Basin, China
摘要
Abstract
Polyphenols are basic components in plant tissues and foliar litter,and play an important role in ecosystem functioning.In particular,the dynamics of polyphenol degradation in foliar litter determines the foliar litter decomposition to some extent.It is well-documented that litter decomposition and the degradation of basic components,such as cellulose and lignin,in litter are affected by precipitation,litter quality,soil organisms,and their interactive effects.Considerable attention has been given the effects of abiotic and biotic factors on mass loss,element releases,and the degradation of lignin and cellulose.However,there is little information available on the effects of seasonal precipitation patterns on the dynamics of polyphenol degradation in decomposing litter.To understand the characteristics of foliar litter decomposition as affected by seasonal rainfall pattern in the subtropical evergreen broad-leaved forest region,a litterbag decomposition experiment was conducted at the Chongzhou Modern Agricultural Research & Development Base at Sichuan Agricultural University,China.The dynamics of polyphenol degradation in the decomposing needle litter of Pinus massoniana,Cryptomeria fortunei,and Cunninghamia lanceolata,and in the decomposing broadleaved foliar litter of Cinnamomum camphora,Toona ciliata,and Quercus acutissima in the subtropical evergreen broad-leaved forest in the upper reaches of Yangtze River,China were therefore investigated at different critical periods.From the micro rainy stage to the early rainy stage,the polyphenol degradation rates in the decomposing litter of the six tree species increased continually as rainfall levels rose and thereafter,the concentrations of polyphenols in the remaining litter were stable.During the first decomposition year,the polyphenol degradation rates were in the order:T.ciliate (100％) ＞ C.fortunei (97.81％) ＞ C.lanceolata (94.45％) ＞ Q.acutissima (93.67％) ＞ P.massoniana (93.06％) ＞ C.camphora (91.64％).The amounts of litter polyphenols degraded during the two dry stages accounted for 42.16％-71.20％ in the early decomposition period,depending on tree species.Furthermore,except for C.camphora,44.46％-55.72％ of the polyphenols in the foliar litter of the other five tree species were degraded during the early rainy stage.The initial concentrations of polyphenols in foliar litter showed a significant quadratic function with the rate of litter polyphenol degradation,which implied that the initial concentration of polyphenols in foliar litter,as determined by tree species,is a key factor that affected litter quality and drove the litter polyphenol degradation process to a great extent.In conclusion,precipitation pattern is the crucial factor in driving the degradation of foliar litter polyphenols,while litter quality,as determined by tree species,is the internal factor regulating the polyphenol degradation dynamics of foliar litter in the humid subtropical evergreen broad-leaved forest regions.关键词
凋落物分解/多酚/季节性降雨/旱季/树种/亚热带地区Key words
litter decomposition/polyphenols/seasonal rainfall/dry season/tree species/subtropical region引用本文复制引用
马志良,杨万勤,吴福忠,谭波..四川盆地亚热带常绿阔叶林凋落叶多酚类物质在不同降雨期间的降解特征[J].生态学报,2018,38(9):3078-3085,8.基金项目
国家自然科学基金项目(31570445,31670526,31622018) （31570445,31670526,31622018）
