摘要
通过研究桉树纯林与桉树和降香黄檀混交林土壤对香豆酸、香草酸和水杨酸的吸附动力学、等温吸附与解吸特性,探讨3种酚酸在不同林分土壤中的累积特征,评价桉树纯林引入降香黄檀后对林分酚酸物质累积的影响。采集5年生巨尾桉广林9号纯林及其与降香黄檀混交林地0~30 cm土层的土壤,采用添加外源酚酸方法和高效液相色谱仪检测酚酸吸附与解吸量。结果表明,3种酚酸在纯林与混交林土壤中的吸附都属于物理吸附,均表现4 h内快速吸附、4~24 h慢速吸附,随后逐渐达到吸附平衡;桉树纯林对酚酸的吸附速率大于混交林,随时间延长,纯林与混交林对酚酸的吸附速率基本一致。桉树纯林对酚酸的吸附动力学过程与Langmuir方程更吻合,而桉树与降香黄檀混交林与Elvoich方程更吻合。桉树纯林和混交林对酚酸的吸附过程与酚酸初始浓度呈正相关关系;2种林分土壤对不同酚酸的吸附量总体呈现为香豆酸>水杨酸>香草酸,且桉树纯林吸附量高于混交林;Freundlich方程能够较好地反映桉树纯林与混交林对酚酸的等温吸附特性。在2种林分土壤中香豆酸有一定的解吸率,香草酸和水杨酸解吸率较小甚至未发生解吸行为。香豆酸在高浓度400μg·mL^(-1)时,混交林土壤的解吸率显著高于纯林,而低浓度时纯林土壤的解吸率高。
To understand the accumulation mechanisms of three phenolic acids(coumaric acid, vanillic acid, and salicylic acid) in the soil of a pure Eucalyptus plantation and mixed plantation of Eucalyptus×Dalbergia odorifera, the adsorption kinetics and isotherm adsorption and desorption characteristics were investigated to evaluate the effect of introducing D. odorifera into a Eucalyptus plantation and its effects on phenolic acid accumulation in stands. The soils of the 0~30 cm layer were sampled in 5-year-old Eucalyptus and mixed plantations and used to measure the amounts of phenolic acid adsorption and desorption by adding exogenous phenolic acid and high-performance liquid chromatography. The results showed the following physical adsorption characteristics for three phenolic acids in the soils of the pure and mixed plantations: rapid adsorption within 4 h, slow adsorption within 4~24 h, and a gradual equilibrium. The phenolic acid adsorption rates in the pure plantation of Eucalyptus were higher than those of the mixed plantation but tended to be the same gradually. The adsorption kinetics of phenolic acid in the pure Eucalyptus plantation were more consistent with the Langmuir equation, while those in the mixed plantation were more consistent with the Elovich equation. The adsorption of phenolic acids in the pure plantation was positively correlated with the initial phenolic acid concentrations. The adsorption capacities of the different phenolic acids in the two stand soils were coumaric acid>salicylic acid>vanillic acid, and the adsorption capacity of the pure plantation was higher than that of the mixed plantation. The Freundlich equation can better reflect the isothermal adsorption characteristics of phenolic acids between the pure and mixed plantations. Although there was a specific coumaric acid desorption rate in the soils of the two plantations, the desorption rates of vanillic acid and salicylic acid were low or nonexistent. At a high coumaric acid concentration(400 μg·mL-1), the desorption rate in the mixed plantation soil was significantly higher than that in the pure plantation, while the desorption rate of the pure plantation soil was higher at a low concentration.
作者
张艳玲
覃天联
杨梅
梁燕芳
廖承锐
ZHANG Yanling;QIN Tianlian;YANG Mei;LIANG Yanfang;LIAO Chengrui(College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Guangxi State-owned Qipo Forest Farm,Nanning,Guangxi 530225,China)
出处
《森林与环境学报》
CSCD
北大核心
2021年第4期343-350,共8页
Journal of Forest and Environment
基金
广西林业科技推广示范项目(科学研究与技术攻关类)(桂林科研[2021]21号)
国家自然科学基金项目(31260176)。
关键词
土壤
酚酸
吸附
桉树
降香黄檀
soil
phenolic acids
adsorption
Eucalyptus
Dalbergia odorifera
