【摘要】 采用常规手段研究了土壤在受氯氰菊酯、铜及二者复合污染后土壤呼吸率及微生物量碳的变化,采用了分离效果较好的双变性梯度凝胶电泳(DG-DGGE)技术研究微生物群落的变化。结果表明,低浓度的铜与高浓度的氯氰菊酯复合污染更能促进微生物量碳及土壤呼吸率的增加,微生物的群落结构也会受到明显影响。而两种污染物分别单独作用时,铜对微生物的胁迫更大,有铜组和无铜组在DGGE条带上差异较大,Shannon指数上也有明显不同。当铜的浓度较高时,加入高浓度的氯氰菊酯在较长的时间后(60d)对土壤呼吸作用、微生物量碳有一定影响,可能高浓度氯氰菊酯的加入在一定程度上减弱了高浓度铜对微生物的胁迫,而微生物群落并无显著的变化。更多还原

【Abstract】 The effects of copper, cypermethrin and their combined applications on soil respiration and microbial biomass carbon were studied using the traditional methods. The structural diversity of soil microbial communities was also studied using the denaturing gradient gel elec trophoresis(DGGE), and the double gradient-denaturing gradient gel electrophoresis was used for providing improved resolution of the bands. The results indicated that the soil respiration and the microbial biomass carbon increased when lower concentration of copper and higher concentration of cypermethrin were applied together, and microbial communities were also significantly affected. When copper and cypermethrin were applied alone, soil respiration and microbial biomass carbon were affected largely by copper, and the DGGE bands also showed significantly differences. It also showed significantly differences on Shannon indexes. When the concentration of copper was higher, the application of higher concentration of cypermethrin affected the soil respiration and microbial biomass carbon in a way but had little effect on the structural diversity of microbial communities; maybe higher concentration of cypermethrin could weaken higher concentration of copper’s stress on microbial communities.更多还原