针对沉积物中沉积磷(P)通过微生物活动再释放,致使湖泊富营养化反复的问题,采集郑州大学眉湖上覆水和沉积物,搭建一个沉积式微生物燃料电池(Sediment Microbial Fuel Cell,SMFC)系统,研究了通过SMFC限制沉积磷向上覆水体释放的方法。实...针对沉积物中沉积磷(P)通过微生物活动再释放,致使湖泊富营养化反复的问题,采集郑州大学眉湖上覆水和沉积物,搭建一个沉积式微生物燃料电池(Sediment Microbial Fuel Cell,SMFC)系统,研究了通过SMFC限制沉积磷向上覆水体释放的方法。实验周期内监测SMFC的电压和阳极电极电位、上覆水温度pH、沉积物磷的Standards Measurements and Testing(SMT)法分级提取;并在实验开始与结束收集阳极微生物样进行微生物群落及基因分析;首次使用氧化锆薄膜扩散梯度技术(Zr-Oxide Diffusive Gradients in Thin-films,Zr-Oxide DGT)可视化了SMFC沉积物中不稳定磷亚毫米分辨率的浓度分布。结果表明:SMFC阳极电极电位从-100 mV升至230 mV;上覆水pH从7.15升至7.46;SMFC沉积物烧失量(Loss on Ignition,LOI)从18.31%±0.7%降至13.09%±1.10%,低于对照组的14.29%±2.10%;SMFC显著促进了孔隙水磷向沉积物磷的矿化过程,在沉积物垂向方向上,Na OH-P和HCl-P出现了明显的区域性增加;根据沉积物DGT磷的二维(2D)图像,SMFC使沉积物DGT磷的浓度最低降至初始值的66%;基于京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)数据库的功能基因分析,SMFC使磷相关功能基因丰度显著增加。证明SMFC对于沉积物磷和水相磷分布有显著影响,通过基质竞争、提高阳极电位等方式减弱固相磷的溶解,促进水相磷向沉积相磷的转化,可用于富营养化水体原位底泥磷稳定化。该文深入研究了SMFC固磷作用机理,为修复水体内源磷污染提供了一种新思路。展开更多
High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerge...High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerged aquatic plant Ceratophyllum demersum.A comparative study was conducted by setting four treatments:open-circuit SMFC(Control),closed-circuit SMFC(SMFC-c),open-circuit SMFC with C.demersum(Plant),and closed-circuit SMFC with C.demersum(P-SMFC-c).The electrochemical parameters were documented to illustrate the bio-electrochemical characteristics of SMFC-c and P-SMFC-c.Removal pathways of NO_3^- in different treatments were studied by adding quantitative^(15)NO_3^- to water column.The results showed that the cathodic reaction in SMFC-c was mainly catalyzed by aerobic organisms attached on the cathode,including algae,Pseudomonas,Bacillus,and Albidiferax.The oxygen secreted by plants significantly improved the power generation of SMFC-c.Both electrogenesis and plants enhanced the complete removal of NO_3^- from the sediment–water system.The complete removal rates of added^(15)N increased by 17.6% and 10.2% for SMFC-c and plant,respectively,when compared with control at the end of experiment.The electrochemical/heterotrophic and aerobic denitrification on cathodes mainly drove the higher reduction of NO_3^- in SMFC-c and plant,respectively.The coexistence of electrogenesis and plants further increased the complete removal of NO_3^- with a rate of 23.1%.The heterotrophic and aerobic denitrifications were simultaneously promoted with a highest abundance of Flavobacterium,Bacillus,Geobacter,Pseudomonas,Rhodobacter,and Arenimonas on the cathode.展开更多
文摘针对沉积物中沉积磷(P)通过微生物活动再释放,致使湖泊富营养化反复的问题,采集郑州大学眉湖上覆水和沉积物,搭建一个沉积式微生物燃料电池(Sediment Microbial Fuel Cell,SMFC)系统,研究了通过SMFC限制沉积磷向上覆水体释放的方法。实验周期内监测SMFC的电压和阳极电极电位、上覆水温度pH、沉积物磷的Standards Measurements and Testing(SMT)法分级提取;并在实验开始与结束收集阳极微生物样进行微生物群落及基因分析;首次使用氧化锆薄膜扩散梯度技术(Zr-Oxide Diffusive Gradients in Thin-films,Zr-Oxide DGT)可视化了SMFC沉积物中不稳定磷亚毫米分辨率的浓度分布。结果表明:SMFC阳极电极电位从-100 mV升至230 mV;上覆水pH从7.15升至7.46;SMFC沉积物烧失量(Loss on Ignition,LOI)从18.31%±0.7%降至13.09%±1.10%,低于对照组的14.29%±2.10%;SMFC显著促进了孔隙水磷向沉积物磷的矿化过程,在沉积物垂向方向上,Na OH-P和HCl-P出现了明显的区域性增加;根据沉积物DGT磷的二维(2D)图像,SMFC使沉积物DGT磷的浓度最低降至初始值的66%;基于京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)数据库的功能基因分析,SMFC使磷相关功能基因丰度显著增加。证明SMFC对于沉积物磷和水相磷分布有显著影响,通过基质竞争、提高阳极电位等方式减弱固相磷的溶解,促进水相磷向沉积相磷的转化,可用于富营养化水体原位底泥磷稳定化。该文深入研究了SMFC固磷作用机理,为修复水体内源磷污染提供了一种新思路。
基金supported by the National Key Research and Development Plan of China (No. 2016YFC0500403-03)the Science and Technology Service Network Initiative of the Chinese Academy of Sciences (No. KFJ-STS-ZDTP-038)
文摘High nitrate(NO_3^-)loading in water bodies is a crucial factor inducing the eutrophication of lakes.We tried to enhance NO_3^-reduction in overlying water by coupling sediment microbial fuel cells(SMFCs)with submerged aquatic plant Ceratophyllum demersum.A comparative study was conducted by setting four treatments:open-circuit SMFC(Control),closed-circuit SMFC(SMFC-c),open-circuit SMFC with C.demersum(Plant),and closed-circuit SMFC with C.demersum(P-SMFC-c).The electrochemical parameters were documented to illustrate the bio-electrochemical characteristics of SMFC-c and P-SMFC-c.Removal pathways of NO_3^- in different treatments were studied by adding quantitative^(15)NO_3^- to water column.The results showed that the cathodic reaction in SMFC-c was mainly catalyzed by aerobic organisms attached on the cathode,including algae,Pseudomonas,Bacillus,and Albidiferax.The oxygen secreted by plants significantly improved the power generation of SMFC-c.Both electrogenesis and plants enhanced the complete removal of NO_3^- from the sediment–water system.The complete removal rates of added^(15)N increased by 17.6% and 10.2% for SMFC-c and plant,respectively,when compared with control at the end of experiment.The electrochemical/heterotrophic and aerobic denitrification on cathodes mainly drove the higher reduction of NO_3^- in SMFC-c and plant,respectively.The coexistence of electrogenesis and plants further increased the complete removal of NO_3^- with a rate of 23.1%.The heterotrophic and aerobic denitrifications were simultaneously promoted with a highest abundance of Flavobacterium,Bacillus,Geobacter,Pseudomonas,Rhodobacter,and Arenimonas on the cathode.
