金霉素在不同耕作土壤中的吸附－解吸行为

用批平衡吸附试验研究了金霉素在河南封丘潮土、南京黄棕壤、常熟水稻土和江西鹰潭红壤4种土壤中的吸附行为。结果表明,金霉素的土壤吸附-解吸行为均可用Freundlich模型和Langmuir模型进行良好的线性拟合。其Kf值差异较大,分别为潮土1135Lkg-1,黄棕壤1250Lkg-1,水稻土2618Lkg-1和红壤4315Lkg-1,显示金霉素在4种土壤中的吸附行为存在较大的差异。此外,金霉素在4种土壤上的解吸过程存在明显的滞后现象。研究还表明4种土壤中金霉素的吸附参数Kf值与土壤pH呈显著负相关。

Adsorption-desorption of chlortetracycline in various cultivated soils in China

A batch equilibrium experiment was carried out to study adsorption and desorption of Chlortetracycline (CTC) in four types of soils, namely Ustic Cambosols collected form Fengqiu of Henan, Udic Argosols collected from Nanjing of Jiangsu, Gleyic-Stagnic Anthrosols collected from Changshu of Jiangsu and Ali-Perudic Ferrosols collected from Yingtan of Jiangxi. Results show that the linear model is not appropriate to describe any of the experimental sorption-desorption data, while the Freundlich model and the Langmuir model fit pretty well. Different sorption behaviors of Chlortetracycline were observed in the four tested soils, with Kf values varying sharply, 1 135 L kg~(-1) for Cambosols; 1 250 L kg~(-1) for Argosols; 2 618 L kg~(-1) for Anthrosol; and 4 315 L kg~(-1) for Ali-Haplic Acrisol. The apparent sorption/desorption hysteresis was quantified for each sample. It had been observed that Kf values are in a significantly negative correlation with soil pH.