中文摘要：

为了解硫丹对棕壤生态系统的毒性影响,采用室内避光培养模拟实验,设定硫丹在土壤中的浓度分别为0.1、1、10 mg·kg^-1,取样时间为7、14、21、28 d,测定土壤中脲酶、脱氢酶和β-葡糖苷酶活性的变化,同时采用变性梯度凝胶电泳（PCR-DGGE）分子指纹技术研究硫丹在不同培养时间对土壤中细菌群落结构的影响。结果表明：土壤脲酶活性与对照相比无显著差异;脱氢酶活性受到显著抑制,且随着硫丹浓度增大,抑制作用增强;土壤β-葡糖苷酶活性则被显著激活。经BLAST程序与GenBank数据库进行比对分析,低浓度硫丹处理在培养周期28 d内,对棕壤中细菌群落结构没有产生显著的干扰作用。

英文摘要：

A laboratory experiment was performed to evaluate the toxicological effects of endosulfan on some enzymes（urease, dehydroge- nase and β-glucoside） and microbial community structure diversity in a brunisolic soil at different concentrations（0, 0.1, 1 mg and 10 mg endosulfan per kg soil） on the 7, 14, 21 and 28 day of treatment. Endosulfan did not influence soil＇ urease activity, but significantly in- hibited dehydrogenase with stronger suppression at higher concentrations. However, the activity of β-glucoside enzyme was steadily and sig- nificantly enhanced by endosulfan. The DGGE data showed that endosulfan at 0-10 rag. kg-1 had no toxic effects on soil bacterial community structure and activities. In conclusion, endosulfan did not impact bacterial community structure in the brunisnlic soil.