伊乐藻-固定化脱氮微生物技术对入贡湖河道脱氮机制的影响

Effect of Elodea nuttallii-immobilized Nitrogen Cycling Bacteria on Nitrogen Removal Mechanism in an Inflow River,Gonghu Bay

采用无扰动的入贡湖亲水河底泥柱芯以及上覆水进行实验,探究了伊乐藻与固定化脱氮微生物技术对受污染的入贡湖湾河道的生态修复效果.运用稳定性15N同位素配对技术和基于16S rRNA高通量测序技术探讨了伊乐藻与固定化脱氮微生物联用技术(E-INCB)对亲水河底泥的反硝化速率、厌氧氨氧化速率以及脱氮微生物群落多样性的影响.结果表明,添加了伊乐藻与固定化脱氮微生物以后,亲水河水质得到明显改善,TN、NH+4-N、NO-3-N的去除率分别为72.03%、46.67%、76.65%,同时,添加了伊乐藻和固定化脱氮微生物以后,泥水界面的反硝化细菌和厌氧氨氧化细菌表现出协同作用关系,与对照组相比,反硝化速率和厌氧氨氧化速率增加量分别为165μmol·(m2·h)-1和269.7μmol·(m2·h)-1.反硝化细菌与厌氧氨氧化细菌的群落多样性明显增加,变形菌门(Proteobacteria)、浮霉菌门(Planctomycetes)、酸杆菌门(Acidobbacteria)和拟杆菌门(Bacteroidetes)均具有优势增长.沉水植物与固定化脱氮微生物联用技术增强了河道底泥中的脱氮微生物多样性,进一步提高了亲水河的氮素脱除能力.

Undisturbed sediment cores and surface water from Qinshui River in Gonghu Bay were collected to carry out a simulation experiment in our laboratory. The remediation effect of Elodea nuttallii-Immobilized Nitrogen Cycling Bacteria（ INCB） was applied in the polluted inflow river. The denitrification rate,ANAMMOX rate and nitrogen microorganism diversity were measured by15 N isotope pairing technology and high-throughput sequencing technology based on 16 S rRNA. The TN,NH4^＋-N,NO3^--N concentrations were reduced by 72. 03%,46. 67% and 76. 65% in the treatment with addition of Elodea nuttallii and INCB in our laboratory experiment.Meanwhile,denitrification bacteria and ANAMMOX bacteria had synergistic effect with each other. The denitrification and ANAMMOX rates were increased by 165 μmol·（ mm^2·h）^-1. and 269. 7 μmol·（ m^2·h）^-1.,respectively. The diversities of denitrification and ANAMMOX bacteria also increased in our experiment. From the level of major phylum, Proteobacteria, Planctomycetes,Acidobbacteria and Bacteroidetes all increased significantly. The results showed that the Elodea nuttallii-INCB assemblage technology could increase the bio-diversity of nitrogen cycling bacteria and promote the ability of nitrogen removal in Qinshui River.