磺胺类抗生素在土壤-植物系统中的迁移特征

Transport processes of sulfonamide antibiotics in soil-plant system

通过土柱淋溶实验和盆栽实验,以小白菜为供试植物,对两种磺胺类抗生素——磺胺嘧啶(SDZ)和磺胺二甲基嘧啶(SMT)在土壤(黑土、棕壤)-植物系统中的迁移特性及影响因素进行了研究。结果表明:SDZ在土柱中的迁移能力高于SMT,两者在土柱中的迁移能力均随土层深度的增加而减弱;延长淋溶时间和增加抗生素浓度,可增强SDZ和SMT在相同深度土层的迁移能力;磺胺类抗生素在不同类型土壤中的迁移能力不同,SDZ和SMT在棕壤中的迁移能力高于黑土;磺胺类抗生素在土壤中的迁移能力会影响农作物对其的吸收和转移,SDZ从土壤迁移至小白菜体内的能力高于SMT,两者主要分布在小白菜的茎叶部分,随SDZ和SMT淋溶浓度的增加,小白菜体内残留的抗生素浓度也随之升高;与黑土相比,种植于棕壤中的小白菜体内残留的SDZ和SMT浓度较高。

Chinese cabbage, black soil and brown soil were selected to investigate the transfer characteristics of sulfadiazine （SDZ） and sulfamethazine （SMT） and the influence factors in soil-plant system using leaching and pot experiments. The results showed that SDZ had higher transfer ability than SMT in soil. The transfer ability of SDZ and SMT decreased with the increase of soil depth. With prolonged leaching time and increased antibiotic concentration, the transfer ability of SDZ and SMT increased in the same soil layers. The transfer ability of sulfonamides differed with soil type. The transfer ability of SDZ and SMT was higher in brown soil than in black soil. The absorption and transfer of the sulfonamides in plants was impacted by their transfer ability in soil. Chinese cabbage took up more SDZ rather than SMT, and the sulfonamides were mainly detected in the stem and leaf of Chinese cabbage. With the increase of sulfonamide concentration, the residue concentration of sulfonamides in Chinese cabbage was increased. The concentrations of SDZ and SMT in Chinese cabbage were higher in brown than in black soil.