处理重金属废水人工湿地中微生物群落结构和酶活性变化

研究了处理含铜、铬与镍废水的三阶段波形潜流人工湿地中微生物群落结构和酶活性的空间变化. 用稀释平板菌落计数法研究了微生物的数量变化，用PCR-DGGE结合测序研究了微生物群落结构变化，并用比色法测定了土壤酶活性. 结果表明，在人工湿地中，细菌数量为(4.10 ± 0.72)×10⁶ ～ (1.61±0.10)×10⁷，真菌数量为(7.21±1.60)×10⁴ ～(1.29±0.02)×10⁵；放线菌数量为(1.41±0.27)×10⁶ ～(3.38±0.11)×10⁶. 回收自DGGE凝胶中的8个不同的条带均为特异的16S rRNA序列或18S rRNA序列，说明微生物群落结构发生了显著变化. 最大的脲酶活性［（0.67 ± 0.2) mg/(g·24 h）］、蔗糖酶活性［（40.15 ± 0.14) mg/(g·24 h）］和碱性磷酸酶活性［（1.03 ± 0.16) mg/(g·2 h）］分别出现在第1、第3和第1阶段. 相关性分析表明，真菌数与全量铬含量、有效态铬含量和铬的活化率均呈显著负相关，蔗糖酶活性与全量铜、全量镍和有效态镍也均呈显著负相关.

Spatial Difference of Microbial Community Structure and Enzyme Activity in Constructed Wetlands Receiving Wastewater Containing Heavy Metals

The microbial community structure and enzyme activity were investigated in the three-stage wavy subsurface constructed wetland (W-SFCW) receiving wastewater containing heavy metals (Cr, Cu and Ni). Colony forming units (CFU) abundance of microbes was calculated by using plate culture. The microbial community structure was investigated by using PCR-DGGE and sequencing. Enzyme activity was detected by using colorimetry. The results showed that the CFU of bacteria ranged from (4.10 +/- 0.72) x 10(6) to (1.61 +/- 0.10) x 10(7), fungi ranged from (7.21 +/- 1.60) x 10(4) to (1.29 +/- 0.02) x 10(5) and actinomycetes ranged from (1.41 +/- 0.27) x 10(6) to (3.38 +/- 0.11) x 10(6). All of 8 bands retrieved from DGGE gels were unique 16S rRNA or 18S rRNA sequences and revealed that the microbial community structures had changed spatially. Maximum urease (0.67 +/- 0.2) mg/(g x 24 h)], invertase (40.15 +/- 0.14) mg/(g x 24 h)] and alkaline phosphatase (1.03 +/- 0.16) mg/(g x 2 h)] activities were at first stage, third stage and first stage, respectively. A negative correlation between fungi CFU abundance and the total content of Cr, available Cr content and activation rate of Cr was detected, a negative correlation was also found between the invertase activity and total Cu and Ni contents and the Ni activation rate.