吸附–解吸是影响抗生素类污染物在土壤中迁移转化及生物有效性的重要过程,本文以川中丘陵区坡耕地紫色土为研究对象,通过批量平衡实验和柱实验研究生物质炭施用(投加量0 (B0)、39.75 t/hm2(B1)和198.75 t/hm2 (B2))及田间老化作用(夏季干湿交替)对3种典型磺胺类抗生素(磺胺嘧啶(SD)、磺胺二甲基嘧啶(SM2)及磺胺甲恶唑(SMZ))在紫色土中的吸附–解吸和淋溶行为的影响.结果表明:在几种处理中,3种磺胺类抗生素吸附强弱的顺序都表现为SD>SMZ>SM2;与B0处理相比,添加生物质炭能增加土壤对3种抗生素的吸附能力,其中SM2的吸附显著增加(P<0.05),但这种促进作用在经过老化过程后有所减弱.在解吸过程中,3 种抗生素的 Freundlich 常数 Kf大小顺序为SD>SMZ>SM2,表明SD在土壤中吸附容量最大且不易解吸,其次是SMZ和SM2;相应的迟滞系数H大小顺序为SDSMZ>SM2; Compared with B0, addition of fresh biochar enhanced the adsorption of SD, SM2 and SMZ, among which the improvement for SM2 was significant (P<0.05), but such effect became less obvious after the ageing process. As for the desorption process, the value of Freundlich coefficient Kfof three sulfonamides followed the order of SD>SMZ>SM2, indicating that SD had the highest adsorption capacity and lowest desorption capacity with SM2 inversely. The hysteresis coefficient (H) of three sulfonamides followed the order of SD展开▼
