中文摘要：

为明确螺螨酯对土壤微生物数量和酶活性的毒性效应,采用室内培养方法,研究了经1.0、5.0和10.0 mg/kg 3个浓度螺螨酯处理后供试土壤中微生物数量和土壤酶活性的变化。结果表明,各浓度螺螨酯对细菌数量具有抑制作用,浓度越高,抑制作用越强,而螺螨酯对土壤真菌数量有刺激作用,其中低浓度（1.0 mg/kg）处理对真菌刺激作用最大;随着时间的延长,各浓度螺螨酯处理对土壤微生物数量影响有减弱趋势。螺螨酯对土壤脲酶、蔗糖酶和β-葡萄糖苷酶活性表现为抑制作用,并随浓度升高而增强;脱氢酶活性对螺螨酯表现为刺激-抑制-逐渐恢复的变化趋势;低浓度（1.0 mg/kg）螺螨酯处理14 d后,4种土壤酶活性均可恢复至对照水平,而中浓度（5.0 mg/kg）和高浓度（10.0 mg/kg）螺螨酯处理土壤酶活性恢复则需较长时间。该研究结果可为螺螨酯对土壤微生物的安全性评价和合理使用提供科学依据。

英文摘要：

Toxic effects of spirodiclofen （1.0, 5.0, and 10.0 mg/kg） on soil population and enzyme activities were studied under laboratory control condition. The results showed that all concentrations of spirodiclofen had inhibitory effect on soil bacteria and the inhibitory effect was enhanced with increasing concentration. However, spirodiclofen had stimulatory effect on soil fungi, and the stimulatory effect was the strongest in the soil treated with 1.0 mg/kg spirodiclofen. With the extension of time, the effect of spirodiclofen on soil microbial population was gradually reduced. Spirodiclofen had inhibitory effect on soil urease, invertase and β-glucosidase, and the inhibitory effect increased with the increasing concentration. The dehydrogenase change trend of timulation-inhibition-recover was observed in soil treated with spirodiclofen. The activities of four soil enzymes were recovered to the control levels after 14 days in low concentration （1.0 mg/kg） treatment. However, longer time was needed to recover the activities of four enzymes in soil polluted with moderate （5.0 mg/kg） and high （10.0 mg/kg） concentrations of spirodiclofen. The results of the study would provide scientific basis for soil microbial safety evaluation and reasonable use.