微生物强化组合浮床净化微盐碱水体的效果

Purification of Slightly Salt-alkaline Water Bodies by Microorganism Enhanced Combined Floating Bed

为了研究盐生植物碱蓬(Suaeda salsa)和微生物构建的组合型浮床对微盐碱水体的净化效果,构建空白对照浮床A、碱蓬植物浮床B、微生物浮床C和碱蓬+微生物组合型浮床D,在室内连续流条件下对富营养化微盐碱水体(pH值为8.5~9.0,盐度为5‰~7‰)进行动态净化实验.结果表明,碱蓬植物浮床对总氮、总磷、高锰酸盐指数的去除率分别为32.5%、14.3%和28.2%,增加微生物人工介质后,碱蓬+微生物组合浮床对水体中的总氮、总磷、高锰酸盐指数的净化效率达到70.5%、34.7%、70.8%,其中微生物单元对总氮、总磷、高锰酸盐指数的去除率分别为37.7%、21.6%、44.5%.碱蓬+微生物组合型浮床净化硝态氮、总氮的增效作用去除率分别为12.2%、0.3%,而在去除氨氮、总磷、高锰酸盐指数的过程中没有产生增效作用;表明在微盐碱环境中,组合型浮床中植物和微生物的协同增效作用受到抑制.采用高通量测序技术对浮床C、D中微生物群落进行对比分析表明,组合型浮床中微生物群落具有更高的丰富度和多样性,这与浮床D具有较高的污染物去除率的结果相一致.主成分分析结果表明,微生物的降解作用是水体中污染物浓度降低的主要因素.本研究为组合型浮床应用于净化滨海区富营养化微盐碱水体提供了参考依据.

In order to study the purifying effect of combined floating bed constucted by salinity plant Suaeda salsa and microorganisms on the slightly salt-alkaline water, blank floating bed A, S.salsa floating bed B, microbes floating bed C and S.salsa ＋ microorganisms combined floating bed D were established, and slightly salt-alkaline eutrophic water body （pH 8.5-9.0, salinity 5‰-7‰） was purified under continuous flow conditions in the laboratory. Results showed that the removal rates of total nitrogen, total phosphorus, permanganate index by S.salsa floating bed were 32.5%, 14.3% and 28.2%, respectively. And the removal rates of total nitrogen, total phosphorus and permanganate index by S.salsa ＋ microorganisms combined floating bed D which installed artificial medium with microorganisms reached 70.5%, 34.7% and 70.8%, respectively, of which the removal rates of total nitrogen, total phosphorus and permanganate index by microbial units were 37.7%, 21.6% and 44.5%, respectively. Synergies removal rates of nitrate nitrogen and total nitrogen by S.salsa ＋ microorganisms combined floating bed were 12.2% and 0.3%, but there was no synergy in the process of removing ammonia nitrogen, total phosphorus and permanganate index, which indicated that the synergies of S.salsa and microorganisms in the combined floating bed were suppressed in slightly salt-alkaline environment. The high-throughput sequencing technique was adopted to analyze the microbial community in the floating bed C and D, which indicated that the abundance and diversity of microbial community in the combined floating bed were higher, and this was consistent with the result of the higher removal rate of the flotation bed D. Principal component analysis showed that the microbial degradation was a major factor in reducing the concentration of pollutants. This study provided a guide for the using of floating bed in purifying slightly salt-alkaline eutrophic water bodies in coastal area.