外源四环素对菜田土壤微生物活性及数量的影响

通过向土壤中添加四环素溶液的方法研究了油菜种植条件下,不同浓度(0.3,0.6,0.9mg/kg)的外源四环素对土壤微生物活性及数量的影响,以评价其环境生态效应。结果表明,土壤中加入四环素后,不同浓度的四环素药物对微生物量碳的影响表现为抑制作用,在27d达到最低,为空白的6.25%～11.97%;而对土壤代谢商qCO2却表现出明显的激活作用,7d达到最高,为空白的550%～622%,且微生物活性的受抑制—激活程度及持续时间与处理浓度成负相关,50d后施药土壤和对照组土壤的代谢商qCO2基本趋于一致。土壤中加入四环素后,各浓度处理对土壤微生物数量有强烈的抑制作用。

Effects of Extraneous Tetracycline on Soil-microbial Activity and Microbial Population of Vegatable Field

This study focused on the effects of tetracycline with different contents (0. 3,0. 6,0. 9 mg/kg) on the soil-microbial activities as well as the microbial population by addition of exogenous tetracycline under the rape field planting. The results showed that the activities of microbial biomass under the treatments of different contents of tetracycline were restrained, it reached the lowest level at the 27th day, and it was the CK 6.25%~11.97%; However, different contents of tetracycline activated the soil metabolic quotient obviously.It reached the highest level at the 7th day, and it was the CK 550%~622%. The restrain or activation extents and the conserving time of microbial activities had a significant negative correlation with the tetracycline contents. The activities of soil metabolic quotients in soils treated with tetracycline and those of CK tended to be similar 50 days after treatment. The tetracycline at each concentration tested had significant inhibitory effect on soil microbial population.