铁-碳共基质环境对污水铁型反硝化效率和微生物群落的影响  

Effects of Fe-C co-substrate environment on iron-based denitrification efficiency and microbial community in wastewater

作　　者：郑蕾[1] 吴浩鸣 王雪 程莉蓉[1] 谭秋阳 邢钰梓 田淇 张耀鑫 ZHENG Lei;WU Hao-ming;WANG Xue;CHENG Li-rong;TAN Qiu-yang;XING Yu-zi;TIAN Qi;ZHANG Yao-xin(College of Water Science,Beijing Normal University,Beijing 100875,China)

机构地区：[1]北京师范大学水科学研究院,北京100875

出　　处：《中国环境科学》2024年第10期5472-5480,共9页China Environmental Science

基　　金：国家重点研发计划项目(2021YFE0192500)。

摘　　要：构建共基质亚铁型反硝化系统,通过梯度实验探究共基质条件下低浓度有机碳(0,3,6,9,12mg/L)对不同Fe/N(2,3,4)条件下铁型反硝化的作用规律和机制,为提升铁型反硝化的效能提供理论参考.结果表明,本实验中有机碳源的最佳浓度为9mg/L.在Fe/N=3和4时,脱氮效率相比未添加碳源时分别提升22.7%和9.1%,促进效果随着外加碳源浓度和Fe/N的升高而减弱.添加有机碳对微生物群落的多样性和均匀度影响较小,随着浓度的升高系统中的自养型细菌如Rhodanobacter和混合营养型细菌如Comamonas,Thauera在生态网络中的总节点度始终高于异养型反硝化菌.C/Fe=0.140和0.187(即碳源浓度为6mg/L和9mg/L)时生态网络中协同和共生关系超过65%,碳源分别实现了单位浓度增益效果最高和反硝化效能最高,自养过程对系统反硝化的贡献度分别为39.2%和56.5%,均为主导地位.系统中主导NO3-,NO2-和NO还原的功能基因丰度的上升,也是提升铁型共基质反硝化系统脱氮效能的重要原因.A co-substrate ferrous denitrification system was constructed and the effects and mechanisms of low-concentration organic carbon(0,3,6,9,12mg/L)on iron-based denitrification under different Fe/N(2,3,4)conditions were investigated by gradient experiments,providing theoretical reference for improving the efficiency of iron-based denitrification.The results showed that the optimal concentration of organic carbon source was 9mg/L in this experiment.When Fe/N=3 and 4,the denitrification efficiency increased by 22.7%and 9.1%respectively compared with that without carbon source,and the promotive effect decreased with the increase of carbon source concentration and Fe/N.The addition of organic carbon had little effect on the diversity and evenness of microbial communities.With the increase of concentration,the total node degree of autotrophic bacteria such as Rhodanobacter and mixotrophic bacteria such as Comamonas and Thauera in the ecological network was always higher than that of heterotrophic denitrifying bacteria.When C/Fe=0.140and 0.187(i.e.,carbon source concentrations of 6mg/L and 9mg/L),the synergistic and symbiotic relationship in the ecological network exceeded 65%,and the carbon source achieved the highest gain effect per unit concentration and the highest denitrification efficiency,respectively.The autotrophic process contributed 39.2%and 56.5%,respectively,to the system denitrification,both of which were dominant.The increase in the abundance of functional genes that dominate NO3-,NO2-,and NO reduction in the system is also an important reason for improving the NO3--N removal efficiency of the iron-based co-substrate denitrification system.

关 键 词：共基质 铁型反硝化 微生物群落 微生物生态网络 反硝化贡献度 

分 类 号：X703[环境科学与工程—环境工程]