电子受体和光照对土壤CH_(4)排放相关微生物功能基因丰度的影响  

Effects of electron acceptor and light on the abundance of microbial function gene related to soil CH_(4) emission

作　　者：陈娟 胡琳玉 卢鹏伟 江玉梅[1] 张志斌[1] 曾庆桂[1] 简敏菲[1] 朱笃[1,2] CHEN Juan;HU Lin-yu;LU Peng-wei;JIANG Yu-mei;ZHANG Zhi-bin;ZENG Qing-gui;JIAN Min-fei;ZHU Du(Jiangxi Province Key Laboratory of Protection and Utilization of Subtropical Plant Resources,College of Life Sciences,Jiangxi Normal University,Nanchang 330022,China;Jiangxi Province Key Laboratory of Bioprocess Engineering,College of Life Sciences,Jiangxi Science and Technology Normal University,Nanchang 330013,China)

机构地区：[1]江西师范大学生命科学学院,江西省亚热带植物资源保护与利用重点实验室,南昌330022 [2]江西科技师范大学生命科学学院,江西省生物加工过程重点实验室,南昌330013

出　　处：《应用生态学报》2022年第2期517-526,共10页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31760161);江西省自然科学基金项目(20202BABL203048);江西省教育厅项目(GJJ160314)资助。

摘　　要：为探究光照条件下添加不同电子受体对土壤甲烷排放的影响及微生物的响应,本研究在土壤中添加3种电子受体(Fe^(3+)、NO_(3)^(-)、SO_(4)^(2-))共设计8个处理,即黑暗+Fe^(3+)(DF)、黑暗+NO_(3)^(-)(DN)、黑暗+SO_(4)^(2-)(DS)、黑暗+蒸馏水(DCK)、光照+Fe^(3+)(LF)、光照+NO_(3)^(-)(LN)、光照+SO_(4)^(2-)(LS)、光照+蒸馏水(LCK),通过20 d的严格厌氧培养,分析甲烷浓度的变化以及细菌、古菌、真菌及6种土壤功能微生物基因丰度的变化。结果表明:除Fe^(3+)处理组外,NO_(3)^(-)、SO_(4)^(2-)和对照(CK)组在光照条件下的甲烷排放显著低于黑暗条件下。土壤细菌、古菌、真菌丰度分别在DN、DCK、LF处理组中显著上调。产甲烷菌mcrA、硫酸盐还原菌Dsr、固碳菌CbbL基因丰度均在LF组中显著上调,而甲烷氧化菌pmoA、铁还原菌Geo、反硝化细菌nosZ基因丰度分别在LN、DCK、LCK组中显著上调。Pearson相关性及冗余分析表明,CH_(4)排放与CO_(2)浓度、pH、铵态氮、总氮含量呈显著正相关,与N_(2)O浓度、氧化还原电位、硝态氮、总碳含量呈显著负相关。黑暗条件下甲烷排放浓度与古菌、pmoA基因丰度呈正相关,与其他功能基因均呈负相关。光照条件下甲烷排放浓度与微生物及功能基因丰度均呈负相关。总体上,光照条件下的甲烷排放显著低于黑暗条件下(除Fe^(3+)处理外),说明光照条件有助于甲烷减排,且甲烷排放的增减和环境中的电子受体种类及微生物的功能响应密切相关。To explore the effects of different electron acceptors on soil methane emission and responses of soil microorganisms to different light conditions,a strict anaerobic 20-day incubation experiment was conducted with eight treatments:darkness+Fe^(3+)(DF);darkness+NO_(3)^(-)(DN);darkness+SO_(4)^(2-)(DS);darkness+distilled water(DCK);light+Fe^(3+)(LF);light+NO_(3)^(-)(LN);light+SO_(4)^(2-)(LS);light+distilled water(LCK).The changes of methane concentration in the anaerobic incubation flask and the variation of the abundance of bacteria,archaea,fungi and six soil functional genes were analyzed.Results showed that soil methane emission under NO_(3)^(-),SO_(4)^(2-)addition and control(CK)was significantly lower under light conditions than dark,except the Fe^(3+)treatment.DN,DCK and LF treatments had the highest abundance of bacteria,fungi and archaea genes,respectively.The gene abundance of methanogenic mcrA,sulfate-reducing bacteria Dsr,and carbon-fixing CbbL were significantly upregulated in the LF,while that of methanotrophs pmoA,iron-reducing bacteria Geo,and denitrifying bacteria nosZ were significantly up-regulated in the LN,DCK and LCK,respectively.Results of Pearson correlation and RDA analysis showed that CH_(4) emission was significantly positively correlated with CO_(2) concentration,pH,ammonium-nitrogen,and total N contents,and negatively correlated with N_(2)O concentration,Eh,nitrate,and total C contents.Under dark condition,methane emission was positively correlated with archaea and pmoA genes abundance,and negatively correlated with other genes abundance.Under light condition,methane emission was negatively correlated with the abundance of soil microbe and functional genes.In general,methane emission under light condition was significantly lower than that under dark condition(except for the Fe^(3+)treatment).These results showed that it was helpful to reduce methane emission under light condition,but the increase or decrease of methane emission was closely related to the type of electron acceptors and the

关 键 词：电子受体 湿地土壤 甲烷排放 光照 功能基因丰度 

分 类 号：X16[环境科学与工程—环境科学] S154.3[农业科学—土壤学]