This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days...This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N2O for a magnetic field-sequencing batch reactor(MF-SBR)decreased by34.3%compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN)and ammonia nitrogen(NH4-N)of the MF-SBR were 22.4%and 39.5%higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira)and denitrifiers(Zoogloea),which could reduce N2O to N2,were promoted significantly in the MF-SBR.Enzyme activities(Nir)and gene abundances(nos Z nir S and nir K)for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature.展开更多
采用Illumina Mi Seq高通量测序技术对不同发酵阶段低温大曲的真菌菌群多样性进行解析,探究低温大曲发酵过程中真菌群落结构的演替规律。结果表明,从入库前到拆曲,低温大曲中真菌菌群的超1指数和香农指数分别从156和2.90上升至376和4.29...采用Illumina Mi Seq高通量测序技术对不同发酵阶段低温大曲的真菌菌群多样性进行解析,探究低温大曲发酵过程中真菌群落结构的演替规律。结果表明,从入库前到拆曲,低温大曲中真菌菌群的超1指数和香农指数分别从156和2.90上升至376和4.29,均依次在上霉、起潮火和潮火阶段出现显著提升(P<0.05)。马氏距离聚类分析结果显示,在潮火阶段之前,各阶段的低温大曲真菌群落结构各不相同,而在潮火阶段之后,群落结构趋于稳定。低温大曲发酵过程中共注释到9个优势真菌属(平均相对丰度>1.0%),包括覆膜孢酵母菌属(Saccharomycopsis)、威克汉姆酵母菌属(Wickerhamomyces)、曲霉属(Aspergillus)等,入库前,以Wickerhamomyces和Saccharomycopsis为主;上霉后,以Saccharomycopsis和根霉菌属(Rhizopus)为主。整个发酵过程中的核心类群由Wickerhamomyces、Saccharomyces和汉逊酵母菌属(Hanseniaspora)等组成,而入库后的特有类群主要由Rhizopus和Saccharomycopsis等组成。由此可见,上霉、起潮火和潮火阶段对低温大曲中真菌丰富度和多样性的提升具有促进作用,且潮火阶段对大曲中真菌群落结构的稳定亦有着积极影响。展开更多
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07202-001-002)
文摘This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N2O for a magnetic field-sequencing batch reactor(MF-SBR)decreased by34.3%compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN)and ammonia nitrogen(NH4-N)of the MF-SBR were 22.4%and 39.5%higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira)and denitrifiers(Zoogloea),which could reduce N2O to N2,were promoted significantly in the MF-SBR.Enzyme activities(Nir)and gene abundances(nos Z nir S and nir K)for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature.
文摘采用Illumina Mi Seq高通量测序技术对不同发酵阶段低温大曲的真菌菌群多样性进行解析,探究低温大曲发酵过程中真菌群落结构的演替规律。结果表明,从入库前到拆曲,低温大曲中真菌菌群的超1指数和香农指数分别从156和2.90上升至376和4.29,均依次在上霉、起潮火和潮火阶段出现显著提升(P<0.05)。马氏距离聚类分析结果显示,在潮火阶段之前,各阶段的低温大曲真菌群落结构各不相同,而在潮火阶段之后,群落结构趋于稳定。低温大曲发酵过程中共注释到9个优势真菌属(平均相对丰度>1.0%),包括覆膜孢酵母菌属(Saccharomycopsis)、威克汉姆酵母菌属(Wickerhamomyces)、曲霉属(Aspergillus)等,入库前,以Wickerhamomyces和Saccharomycopsis为主;上霉后,以Saccharomycopsis和根霉菌属(Rhizopus)为主。整个发酵过程中的核心类群由Wickerhamomyces、Saccharomyces和汉逊酵母菌属(Hanseniaspora)等组成,而入库后的特有类群主要由Rhizopus和Saccharomycopsis等组成。由此可见,上霉、起潮火和潮火阶段对低温大曲中真菌丰富度和多样性的提升具有促进作用,且潮火阶段对大曲中真菌群落结构的稳定亦有着积极影响。
