摘要
采用室内实验方法,研究了3种低分子有机酸对两种可变电荷土壤吸附铜的影响。结果表明,有机酸对铜吸附的影响与有机酸的种类和土壤类型有关,柠檬酸和苹果酸能显著增加可变电荷土壤对铜的吸附,而草酸在低浓度下对铜吸附有一定的增加作用,随着草酸加入量的增加其主要表现为对铜吸附的抑制作用。有机酸主要通过与铜形成表面三元络合物来增加铜的吸附量,以这一机制吸附的铜不能为中性盐NaNO3交换而解吸,因此可以降低铜的活动性和生物有效性。
Effect of low molecular weight organic carboxylic acids on adsorption of copper by variable charge soils was investigated using indoor experiment method. The results showed that the effect was related to the kind of organic acids and the type of soils. The adsorption of copper increased significantly with increased citric acid and malic acid, while the adsorption of copper increased with oxalic acid in lower concentration and decreased with oxalic acid in higher concentration. The increased adsorption of copper by organic acids mainly attributed to the formation of soil- organic acid- cation ternary surface complexes. The copper adsorbed in this manner could not be desorbed by NaNO3, which may reduce the mobility of copper in the soil and the availability of copper to plants.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2004年第2期304-307,共4页
Journal of Agro-Environment Science
基金
中国科学院知识创新工程领域前沿项目(ISSASIP0108
ISSASIP0202)
国家基础规划项目(2002CB410808)
关键词
低分子量有机酸
可变电荷
土壤吸附铜
吸附机理
organic acid
variable charge soil
adsorption of copper
adsorption mechanism
