有机肥源磺胺类抗生素在土壤中的降解规律及影响因素分析

Dynamics and degradation mechanism of antibiotic sulfonamides in soils with organic manure amendment

运用室内模拟降解法,研究了有机肥源磺胺类抗生素(磺胺嘧啶、磺胺甲嘧啶、磺胺二甲嘧啶、磺胺二甲氧嘧啶和磺胺甲恶唑)在光照或避光条件下、不同类型土壤中的降解能力.结果表明,5种磺胺类药物在土壤-粪便混合基质中的降解规律均呈"L"型;不同磺胺在土壤中的降解性与药物自身性质相关,江西红壤中降解半衰期长短顺序为:磺胺甲恶唑>磺胺二甲嘧啶>磺胺嘧啶>磺胺甲嘧啶>磺胺二甲氧嘧啶;土壤中有机质含量越高,磺胺类药物在土壤中降解性越强,其降解速率大小为:东北黑土≈太湖水稻土>江西红壤;磺胺类药物在土壤-粪便混合基质中的降解速率显著大于单一土壤,粪便的加入对磺胺类抗生素的降解性有较大促进作用,光照作用则相对影响较小.

Through the laboratory simulation degradation experiment,the degradation of antibiotic sulfonamides in different soils was studied,including sulfadiazine( SDZ),sulfamerazine( SMZ),sulfamethazine( SMT),sulfadimethazine( SDM),and sulfamethoxazole( SMX). Furthermore,effects of soil physicochemical properties,and presence of organic manure and light were investigated. The results indicated that the degradation rule of five antibiotic sulfonamides in soils with organic manure amendment followed the'L'type. The degradation rate of different sulfonamides was related to the nature of drug,with the degradation half-time in Jiangxi red soil following the order as SMX >SMT >SDZ >SMZ >SDM. It was found that the greater the soil organic content was,the stronger the sulfonamides degradation potential. Degradation rate followed the order of Northeast China black soil ≈ Lake Taihu paddy soil >Jiangxi red soil. It was concluded that addition of manure accelerated the degradation of sulfonamides in soils,while the influence of light was not significant.