中文摘要：

采用盆栽试验法，研究了苏丹草对土壤中菲、芘的去除效果，及植物和微生物在去除土壤菲、芘中的交互效应。结果显示，在试验浓度范围（0-322．06mg·kg^-1内，土壤～苏丹草系统（TR，）对菲、芘的去除效果明显。种植苏丹草60d后，土壤菲、芘去除率分别为73．07％-83．92％、63％～77．62％；平均去除率分别比对照1（无植物，不加0．1％NaN3）高55．58％、50．71％，比对照2（无植物，加0．1％NaN3）高72．71％、66．57％，说明种植苏丹草可以促进微生物对土壤中芘、菲降解。土壤酶活性测定结果也显示，酶活性越高，污染物降解率越高，反之亦然。因此，植物一微生物间的交互效应是土壤中多环芳烃降解的主要途径。

英文摘要：

The effects of Sudan grass（ Sorghum vulgate L. ） and the interaction between plants and microorganisms on the removal of phenanthrene and pyrene from soils were studied by pot experiment in a greenhouse. The results showed that Sudan grass grew normally, and soil-grass system could significantly remove phenanthrene and pyrene from soils at initial concentrations ranging from 0 to 322.06 mg ·kg^-1 for phenanthrene and 0 to 321.42 mg·kg^-1 for pyrene. After 60-day plantation of Sundan grass, the removal rates of phenanthrene and pyrene were 73.07% -83.92% and 63%~77.62% respectively, which were averagely 55.58% and 50.71% higher than those of the CK1（without plants and addition of 0.1% NAN3）, and 72.71% and 66.57% higher than those of CK2（without plants but with addition of 0, 1%NAN3）, respectively. The results suggested that plantation of Sudan grass significantly promoted the microbial degradation of phenanthrene and pyrene. Furthermore, the measurements on the activities of soil urease and polyphenol oxidase also indicated that the enzymes activities decreased with the increase of soil PAHs levels, and the degradation rates of PAHs increased with the increase of soil enzyme activities at the same initial PAHs concentrations. The enzymes activity of the treatment with plantation of Sudan grass （TR3） was higher than those of the two control treatments （ CK1 and CK2） at the same PAHs level, which showed plants growth could enhance the enzymes activity of soil, and promote the PAHs degradation by indigenous microorganisms. Thus the interaction between plants and microorganisms was proved to be the main way for PAHs degradation.