亚热带溪流中树叶凋落物多酚含量对树叶分解过程的影响(英文)  

Effect of Polyphenol of leaf litter on the leaf breakdown in a subtropical Stream

作　　者：官昭瑛[1] 赵颖[2] 童晓立[1] 

机构地区：[1]华南农业大学资源环境学院,广州510642 [2]华南农业大学理学院,广州510642

出　　处：《生态科学》2008年第5期436-438,共3页Ecological Science

基　　金：国家自然科学基金项目(30170121和30270279)

摘　　要：利用邻二氮菲-铁(Ⅲ)分光光度法测定了蒲桃与人面子树叶在二级溪流中分解时植物多酚含量的变化,并研究了多酚含量对树叶分解速率、底栖动物定殖以及微生物呼吸量的影响。结果表明,蒲桃叶片中初始多酚含量(19 %)比人面子树叶的含量高(6 %),其分解速率(分解系数k=0.01 d-1)比人面子树叶慢(k=0.04 d-1 )。研究还发现,蒲桃叶片上的微生物呼吸量比人面子的低(每克叶片单位时间的耗氧量分别为0.2 和0.4毫克),而且底栖动物中撕食者的种类和数量也比人面子树叶少。说明蒲桃叶片中较高的多酚含量抑制了微生物的活性和底栖动物的取食,从而减缓了蒲桃树叶的分解进程,表明叶片中多酚含量与树叶凋落物分解速率呈负相关关系。We used a spectrophotometry method with 1, 10 -phenanthroline-Fe （Ⅲ） to determine the contents of total polyphenol in two species of leaf litter, Dracontomelon duperreanum and Syzygiumjambos. The effects of remaining polyphenolics concentration on decomposition rates, colonization of macroinvertibrates and microbial respiration in a subtropical stream were examined. Results showed that total polyphenol was significantly higher in S. jambos （19%） when compared to D. duperreanum （6%）, and breakdown rate ofS. jambos （k =0.01 day^-1） was slower than that of D. duperreanum （k =0.04 day^-1）. The results also indicated that the average microbial respiration rates （0.2 mg 02 h-1 g DM^-1） ofS. jambos litters was significantly lower than those ofD. duperreanum （ 0.4 mg 02 h^-1 g DM^-1）, and its taxa richness and total density in shredders of macroinvertebrate was significantly less than in those of D. duperreanum （P〈0.05）. The low breakdown rate of S. jambos leaves in the early period is mainly as a result of inhibition of microbial activity as well as less palatable to shredders of macroinvertebrates due to high contents of polyphenols, which showed that the leafpolyphenol had a strong negative effect on leaf litter decomposition.

关 键 词：多酚 树叶分解 亚热带溪流 

分 类 号：Q948.1[生物学—植物学] S718.5[农业科学—林学]