溶解性有机质-四环素-Zn共存体系中土壤对四环素和Zn的吸附作用

Adsorption of Tetracycline and Zine on the Soil in the Dissolved Organic Matter-tetracycline-zinc Coexistence System

以畜禽粪便中的典型组分——溶解性有机质、四环素和锌作为研究对象,以东北典型黑土为供试土壤,采用批次实验法,研究了溶解性有机质、四环素和锌三元混合体系中土壤对四环素和锌的吸附作用。结果表明,土壤对四环素的吸附符合Freundlich吸附模型,土壤对Zn的吸附既符合Langmuir吸附模型,也符合Freundlich吸附模型;四环素和锌之间存在着相互促进吸附的作用;溶解性有机质抑制了四环素在土壤上的吸附,促进了Zn在土壤上的吸附;在溶解性有机质-四环素-Zn混合体系中,四环素和溶解性有机质共存促进了Zn的吸附;而对于四环素的吸附,溶解性有机质和Zn的共存可以表现为促进作用,也可以表现为抑制作用,二者的相对浓度是决定其作用的关键因素。

The soil-adsorption of tetracycline and zinc in the ternary system of dissolved organic matter, tetracy-cline and zinc,which are considered as the three most common contaminants in the fences of livestock and poultry, was studied. The typical black soil from Northeast-China was used as the tested soil, and the batch experiment method was applied for the research. The results indicate that the soil-adsorption of tetracycline fits the adsorption model of Freundlich, and that of Zn fits both the adsorption models of Langmuir and Freundlich. Meanwhile, tetra-cycline and Zn enhance the adsorption each other; the dissolved organic matter inhibits the adsorption of tetracy-cline, and promotes that of Zn. In the dissolved organic matter-tetracycline-Zn system, the coexistence of tetracy-cline and the dissolved organic matter increases the adsorption of Zn; and the coexistence of the dissolved organic matter and Zn can increase or decrease the adsorption of tetracycline, which is dependent on their ratio.