摘要
氮源是影响甲烷氧化菌甲烷氧化效率的重要因素,但其对甲烷氧化过程N_(2)O的生成规律的影响尚不明晰。本研究以甲烷氧化菌混合菌群为供试对象,开展了氮源类型和氮源浓度对甲烷氧化混合菌群甲烷氧化效率和氧化亚氮生成规律的影响试验,并采用乙炔抑制法研究了甲烷氧化混合菌群氧化甲烷过程的N_(2)O生成途径。结果表明:与NH_(4)^(+)-N和NO_(2)^(-)-N相比,以NO_(3)^(-)-N为氮源,甲烷氧化混合菌群具有较高的甲烷氧化效率,可达90%,同时生成的N_(2)O浓度较低,约为1.0 mg/m^(3)。不同浓度的NO_(3)^(-)-N对甲烷氧化混合菌群的甲烷氧化能力和N2O生成影响不大。高浓度NH_(4)^(+)-N会降低甲烷氧化混合菌群的甲烷氧化效率且促进N2O生成,NH_(4)^(+)-N浓度从10 mg/L提高到50 mg/L时,甲烷氧化效率由92.0%降低为78.9%,而N_(2)O浓度由5.1 mg/m^(3)升高为17.8 mg/m^(3)。氧化亚氮产生机制试验表明:甲烷氧化混合菌群在培养初期生成的N_(2)O以非生物作用为主,其贡献约为79%,培养后期以硝化细菌反硝化作用为主,贡献约为61%。
Nitrogen source is one key factor affecting methane oxidation efficiency of methane oxidizing bacteria,but its impacts on N_(2)O production during methane oxidation process is unclear.In this study,we used a mixed methane oxidation bacteria as the test object,and investigated the impacts of nitrogen types and nitrogen concentrations on methane oxidation efficiency and N_(2)O production.Moreover,the N_(2)O production pathway during methane oxidation process was studied via acetylene inhibition methods.The results showed that the mixed methane oxidation bacteria exhibited higher methane oxidation efficiency,which reached up to 90%,when using NO_(3)^(-)-N as the nitrogen source.In addition,the N_(2)O concentration was relatively lower,about 1.0 mg/m^(3).The NO_(3)^(-)-N concentrations had little effects on the methane oxidation efficiency and N2O concentrations of the mixed methane oxidation bacteria.Higher NH_(4)^(+)-N concentrations could decrease the methane oxidation efficiency and increase the N2O formation.As an example,the methane oxidation efficiency decreased from 92.0%to 78.9%and the N_(2)O concentration increased from 5.1 to 17.8 mg/m^(3),when NH_(4)^(+)-N concentration increased from 10 mg/L to 50 mg/L.As for the N2O production pathways,the dominant production pathway in the early stage of cultivation process was the abiotic process,which accounted for 79%of the total N_(2)O emissions,whereas nitrifer denitrification became the main N_(2)O production pathway in the later period of cultivation,as it contributed about 61%to the total N_(2)O emissions.
作者
范玉婧
姚惠娇
高志岭
刘春敬
谢建治
刘臻岳
武新宇
FAN Yujing;YAO Huijiao;GAO Zhiling;LIU Chunjing;XIE Jianzhi;LIU Zhenyue;WU Xinyu(College of Resources and Environmental Sciences/Key Laboratory of Farmland Ecological Environment of Hebei Province,Hebei Agricultural University,Baoding 071000,China;Hebei Animal Husbandry Station,Shijiazhuang 050000,China)
出处
《河北农业大学学报》
CAS
CSCD
北大核心
2021年第3期54-61,共8页
Journal of Hebei Agricultural University
基金
河北省自然科学基金项目(B2019204163)
国家自然科学基金项目(51908189).
关键词
甲烷氧化混合菌群
氮源
甲烷氧化
氧化亚氮
mixed methane oxidation bacteria
nitrogen source
methane oxidation
nitrous oxide
作者简介
第一作者:范玉婧(1995-),女,河北廊坊人,硕士研究生,研究方向为农业环境保护.E-mail:774301616@qq.com;通信作者:刘春敬(1984-),女,河北保定人,博士,副教授,研究方向为农业环境保护.E-mail:chunjingliu2008@163.com。
