1，3-二氯苯污染底泥的零价铁修复对微生物群落结构的影响

Impact of the Remediation of 1,3 -Dichlorobenzene Contaminated Sediments on Microbial Communities Structure Using Zero-Valent Iron

通过采用零价铁修复1,3-二氯苯污染底泥,结合变性梯度凝胶电泳(DGGE)和磷脂脂肪酸(PLFA)技术分析了零价铁修复对底泥微生物群落结构的影响。结果表明,零价铁对底泥中1,3-二氯苯具有较好的去除效果,培养13d后去除率可达70.4%,较未加零价铁的对照处理高50.8%。DGGE指纹图谱分析表明:1,3-二氯苯刺激了底泥中耐受性较高的假单胞菌的增殖;零价铁修复使增殖的耐受菌群的量减少,敏感菌群的量增多,并使底泥微生物的Shannon多样性指数恢复至未污染对照水平。PLFA指纹图谱分析表明:尽管零价铁修复并未恢复底泥中任何一种PLFA的量,但是却恢复G+细菌的量至未污染对照水平。

The remediation of 1,3-dichlorobenzene contaminated sediments using zero-valent iron （ZVI） was studied, and its effect on the microbial community structures were monitored by using 16S rDNA PCR-denaturing gradient gel electrophoresis （DGGE） and phospholipids fatty acid （PLFA） analysis. The results showed that ZVI could remove 1,3-dichlorobenzene effectively, with the removal efficiency 70.4% within a 13 day period, higher than the treatment without ZVI by 50.8%. DGGE fingerprint profiles showed that the 1,3-dichlorobenzene contamination resulted in a significant increase in pseudomonas spp. according to the sequence analysis using BLAST. The bacteria sensitive to 1,3-dichlorobenzene increased and bacteria resistant to 1,3-dichlorobenzene decreased, which may correlate to the decreasing concentration of 1,3-dichlorobenzene using ZVI. Shannon＇s index of diversity （H＇） calculated from DGGE fingerprint data was restored to the control level by ZVI. PLFA fingerprint profiles showed that the PLFA was mainly composed of even-numbered unsaturated fatty acid, while the contents of odd-numbered saturated fatty acid and even-numbered saturated fatty acid were relatively small in amount. Gram-positive bacteria, which were calculated according to the amount of a-15：0, i-15：0 and i-17：0, were significantly restored to the control level by ZVI, although none of the PLFA was restored to the control level.