4种典型抗生素对土壤微生物呼吸的影响

本研究通过室内直接吸收法测定了四环素、金霉素、诺氟沙星和恩诺沙星4种典型抗生素对土壤微生物呼吸作用的影响。结果表明,4种抗生素对土壤微生物呼吸的影响存在一定差异。四环素在整个处理过程中对土壤呼吸的影响以抑制作用为主;金霉素在处理第1d和7d均有激活作用,而且激活率最高可达到51.23%,但是在其他处理时间以抑制作用为主;诺氟沙星在整个处理过程中,浓度为0.2mg·kg-1和1mg·kg-1对土壤微生物呼吸都有一定的抑制作用,浓度为5、25、50mg·kg-1处理均为激活作用,激活作用随着处理浓度的增加而升高。恩诺沙星在整个处理过程中,所有处理对呼吸的影响变化趋势为先激活后抑制。总体来说,到处理第15d,所有抗生素处理的微生物呼吸作用基本恢复到对照水平,说明在本试验浓度处理下,微生物对这4种抗生素能够产生一定的适应性。

Effects of Four Typical Antibiotics on Soil Microbial Respiration

The effects of tetracycline, chlortetracycline, norfloxacin and enrofloxacin on soil microbial respiration were studied using the direct absorption method. The results showed that the effects of these four antibiotics on microbial respiration varied with each other. The soil microbial respiration was mainly inhibited in the tetracycline treatments during the whole incubation. The respiration was improved by chlortetracycline at 1st and 7th and the highest rate was 51.23%, while the respiration was reduced during the other incubation time. The respiration was reduced by norfloxacin（0.2 mg·kg-1 and 1 mg·kg-1） and improved by norfloxacin（5, 25, 50 mg·kg-1） during the whole incubation. In addition, the respiration was improved during the early incubation, while the respiration was reduced with the incubation progressed in the enrofloxacin treatments. There was no significant difference of respiration between the treatments and control at 15th, which suggested that the four antibiotics caused a little risk to soil microbial environment.