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

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。

Adsorption of tetracycline and zine on the soil in the dissolved organic matter -tetracycline-zinc coexistence system

In this paper, the soil-adsorption of tetracycline and zinc in the ternary system of dissolved organic matter , tetracycline 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, tetracycline and Zn enhance the adsorption each other; the dissolved organic matter inhibits the adsorption of tetracycline, and promotes that of Zn. In the dissolved organic matter -tetracycline-Zn system, the coexistence of tetracycline 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.