伊乐藻-高效脱氮微生物协同作用对污染水体氮素脱除机制的影响  

Effect of Elodea nuttallii-Immobilized Nitrogen Cycling Bacteria on the Mechanism of Nitrogen Removal in Polluted River Water

作　　者：王浩[1] 李正魁[1] 张一品[1] 丁帮璟 WANG Hao;LI Zheng-kui;ZHANG Yi-pin;DING Bang-jing(State Key Laboratory of Pollutantion Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China)

机构地区：[1]南京大学环境学院,污染控制与资源化研究国家重点实验室,南京210023

出　　处：《环境科学》2017年第11期4615-4622,共8页Environmental Science

基　　金：国家水体污染控制与治理重大专项(2013ZX07101-014)

摘　　要：在入贡湖河道亲水河采集上覆水、伊乐藻及底泥柱芯样品进行室内实验,探究伊乐藻与固定化高效脱氮微生物协同作用下脱除铵态氮的机制,以及对污染水体的生态修复效果.运用^(15)N同位素配对技术及高通量测序技术,研究了4个不同处理组中NH_4^+的转化机制,其中,处理组A:裸泥组,处理组B:固定化高效脱氮微生物,处理组C:伊乐藻,处理组D:固定化高效脱氮微生物+伊乐藻.结果表明,氮素脱除主要有底泥存储、伊乐藻吸收及微生物过程(反硝化和厌氧氨氧化)这3种途径.在添加沉水植物伊乐藻的处理组C和D中,伊乐藻对^(15)NH_4^+吸收率分别为25.44%和19.79%.不同处理组中底泥对^(15)NH_4^+存储率分别为7.94%、5.52%、6.47%和4.86%,微生物过程以气体形式释放的^(15)NH_4^+分别为16.06%、28.86%、16.93%和33.09%.反硝化和厌氧氨氧化是产生含氮素气体的主要过程,对于处理组D,脱氮微生物丰度和多样性均得到不同程度的提升.4个不同处理组对^(15)NH_4^+的总去除率分别为24%、34.38%、48.84%和57.74%,伊乐藻与高效脱氮微生物联用技术(EINCB)的应用,可以提高水体氮素的脱除速率,促进污染水体的净化.Surface water,Elodea nuttallii and undisturbed sediment cores from the Qinshui River in Gonghu Bay were collected to carry out a simulation experiment in a laboratory to study the effect of Elodea nuttallii-immobilized nitrogen-cycling bacteria on nitrogen removal mechanisms from the river water.In this study,the transformation and fate of ammonium among four different treatment groups were investigated by using a stable ^15N isotope pairing technique combined with high-throughput sequencing technology [Treatment A：bare sediment,Treatment B： sediment ＋ immobilized nitrogen cycling bacteria（INCB）,Treatment C： sediment ＋ E.nuttallii,Treatment D： sediment ＋ INCB ＋ E.nuttallii].The results of the ^15N mass-balance model showed that there were three pathways to the ultimate fate of nitrogen： precipitated with the sediments,absorbed by E.nuttallii,and consumed by microbial processes[denitrification and anaerobic ammonium oxidation（ANAMMOX） ].The percentages of E.nuttallii assimilated in the ^15NH4^＋ were25.44% and 19.79% for treatments C and D.The sediment storage ratio of ^15NH4^＋ accounted for 7.94%,5.52%,6.47% and4.86% in treatments A,B,C,and D,respectively.The proportion of ^15NH4^＋ lost as ^15N-labelled gas were 16.06%,28.86%,16.93% and 33.09% in the four different treatment groups,respectively.Denitrification and anammox were the bacterial primary processes in N2 and N2 O production.The abundance and diversity of microorganisms was relatively higher in the treatment with E.nuttallii-immobilized nitrogen cycling bacteria（E-INCB） assemblage technology applied.Furthermore,the removal rates of ^15NH4^＋ were 24%,34.38%,48.84% and 57.74% in treatments A,B,C and D,respectively.These results show that the E-INCB assemblage technology may improve the capacity for nitrogen removal from the river water.

关 键 词：伊乐藻-固定化高效脱氮微生物联用技术 铵态氮 底泥存储 植物吸收 N2和N2O气体释放 污染水体 

分 类 号：X52[环境科学与工程—环境工程]