两种四环素类抗生素单一及复合污染对农田土壤理化性质和土壤酶活性的影响
Effects of Single and Combined Pollution of Tetracycline Antibiotics on Physiochemical Properties and Enzyme Activities of Farmland Soil
李影 1徐赵虎 2肖雪霞 2曹颖2
作者信息
- 1. 安徽师范大学生态与环境学院,安徽 芜湖 241002;皖江流域退化生态系统的恢复与重建省部共建协同创新中心,安徽 芜湖 241002
- 2. 安徽师范大学生态与环境学院,安徽 芜湖 241002
- 折叠
摘要
多数农业用地土壤中抗生素含量在μg·kg-1水平,而μg·kg-1水平抗生素对土壤质量影响的研究较少,因此开展 0(CK)、10、100 和 500 μg·kg-1土霉素(OTC)和四环素(TC)的单一及复合污染对土壤理化性质和酶活性的影响研究.结果表明:(1)与CK相比,两种抗生素单一处理土壤pH均显著增加,速效磷(OP)含量均显著降低,且TC处理对pH的增长率和对OP的抑制率均显著高于OTC处理,仅 500 μg·kg-1 TC处理可溶性盐显著降低;单一OTC处理OP含量显著降低,有机质(OM)含量增加,多酚氧化酶(PPO)、脲酶(URE)和蔗糖酶(SUC)活性均显著降低;单一TC处理OP、OM和有效氮(AN)含量均显著降低,PPO和SUC活性均显著下降.(2)在单一OTC处理中加入低含量TC能在一定程度上缓解OTC对土壤的毒害,以 10 μg·kg-1 TC+10 μg·kg-1 OTC处理综合缓解效果为最佳;而加入较高含量TC则增大OTC对土壤的毒性,且毒性随着OTC含量增加呈上升趋势,以500 μg·kg-1 TC+500 μg·kg-1 OTC处理毒性最大;各复合处理组PPO活性均被显著抑制,仅 500 μg·kg-1 TC+OTC复合处理URE活性被显著抑制.(3)土壤理化因子与土壤酶活性密切相关,pH是抑制土壤酶活性的关键因子.综上所述,在μg·kg-1含量水平,单一抗生素处理TC毒性整体高于OTC;低、高含量TC与OTC复合处理分别表现为拮抗作用和协同抑制效应.
Abstract
Oxytetracycline(OTC)and tetracycline(TC)are emerging contaminants frequently present at their μg·kg-1 levels in agricultural lands.The effects of μg·kg-1 levels of single and combined pollution of tetracycline antibiotics on soil quality received relatively less attention as yet.In the present study,we spiked 0(CK),10,100 and 500 μg·kg-1 of OTC and TC to farmland soil and tested their single and combined effects in terms of soil physiochemical properties and enzyme activities using pot experiments.Results show that(1)OTC and TC both significantly increased soil pH values and decreased the contents of available phosphorus(OP)compared to the control(CK).Meanwhile,the effects of TC on the growth rate of pH and the inhibition rate of OP were significantly higher than OTCs.Single TC treatment only markedly re-duced electrical conductivity(EC)at 500 μg·kg-1;single OTC treatment significantly decreased OP content but in-creased OM content.In addition,the activities of soil polyphenol oxidase(PPO),urease(URE)and sucrase(SUC)in response to single OTC exposure were significantly lower than the CK.In contrast,single TC treatment significantly de-creased the contents of soil OP,OM and available nitrogen(AN),and reduced the activities of PPO and SUC compared to the control.(2)Addition of low concentration of TC to some extent alleviated the toxic effect of OTC on soil quality,and the optimal mitigation effect was observed at the 10 μg·kg-1 TC+10 μg·kg-1 OTC treatment.In contrast,the addi-tion of relatively higher concentrations of TC enhanced the toxic effects of OTC on soil quality,and such effects increased with the increasing of OTC concentrations;and the highest toxicity occurred at the 500 μg·kg-1 TC+500 μg·kg-1 OTC treatment.PPO activity was significantly reduced in all combined treatments compared to the single OTC treatment,but URE activity was only significantly inhibited in the 500 μg·kg-1 TC + OTC treatment.(3)The redundancy analysis showed a close correlation between soil physicochemical factors and soil enzyme activities,and pH value could be the key factor that inhibits soil enzyme activity.In summary,the toxicity of TC is higher than OTC at their respective μg·kg-1 levels.Low TC levels antagonize and high TC synergize the effect of combined TC and OTC treatments,respectively.
关键词
四环素类抗生素/单一污染/复合污染/土壤理化因子/土壤酶活性Key words
tetracycline antibiotics/single pollution/combined pollution/soil physicochemical factor/soil enzyme activ-ity引用本文复制引用
基金项目
安徽省高校自然科学基金重点项目(KJ2020A0080)
安徽省高校协同创新项目(GXXT-2020-75)
出版年
2024