氮素水平对土壤甲烷氧化和硝化微生物相互作用的影响  

Effects of Nitrogen Levels on Interactions between Active Methanotrophs and Nitrifiers

作　　者：潘红 李勇 孟春梅 郑燕 刘杏梅[1] 诸葛玉平[2] 贾仲君[4] 邸洪杰 徐建明[1] PAN Hong;LI Yong;MENG Chunmei;ZHENG Yan;LIU Xingmei;ZHUGE Yuping;JIA Zhongjun;DI Hongjie;XU Jianming(College of Environmental and Resource Sciences,Provincial Key Laboratory of Agricultural Resources and Environment,Zhejiang University,Hangzhou 310058,China;National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources,College of Resources and Environment,Shandong Agricultural University,Tai’an,Shandong 271018,China;College of Food and Biological Engineering,Zhengzhou University of Light Industry,Zhengzhou 450002,China;Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China)

机构地区：[1]浙江省农业资源与环境重点实验室,浙江大学环境与资源学院,杭州310058 [2]土肥高效利用国家工程研究中心,山东农业大学资源与环境学院,山东泰安271018 [3]郑州轻工业大学食品与生物工程学院,郑州450002 [4]中国科学院南京土壤研究所,南京210008

出　　处：《土壤学报》2022年第2期557-567,共11页Acta Pedologica Sinica

基　　金：国家重点研发计划项目(2016YFD0200302);国家自然科学基金项目(41907026);中国博士后科学基金项目(2020T130387,2019M652448)资助。

摘　　要：甲烷氧化微生物和氨氧化微生物均是既可以氧化甲烷(CH_(4))又可以氧化氨(NH_(3)),氨氧化是硝化作用的限速步骤,也是好氧土壤氧化亚氮(N_(2)O)排放的主要生物路径。选取内蒙古草原围封禁牧土壤为研究对象,利用稳定同位素核酸探针技术(DNA-SIP)探讨不同氮水平下土壤活性甲烷氧化微生物与硝化微生物及其相互作用机制。结果发现低氮添加促进甲烷氧化活性,而高氮添加抑制甲烷氧化活性;低氮和高氮添加均显著增强硝化活性。基于DNA-SIP的高通量测序结果发现Methylobacter MOB和Nitrosospira AOB/Nitrospira NOB分别是该土壤的主要活性甲烷氧化和硝化微生物。网络结构分析发现Methylobacter MOB和Nitrosospira AOB/Nitrospira NOB存在显著负相关关系,进一步证明活性甲烷氧化和硝化微生物之间存在竞争性相互作用。以上结果表明,氮素水平影响草原土壤甲烷氧化和硝化微生物的相互作用,研究结果为采取措施调控草原土壤CH_(4)的汇和N_(2)O的源功能以及减缓气候变暖的进程提供理论基础。【Objective】Ammonia oxidation is the limited step of nitrification and it is the main microbial pathway of N_(2)O emissions in aerobic soils.Grassland soils are sinks for CH_(4)and sources of N_(2)O.However,the mechanisms of the interactions between methane and ammonia oxidation under various N levels in grassland soils remain elusive.【Method】A microcosm experiment was implemented using Inner Mongolia grassland soils based on DNA-Stable-Isotope-Probing(DNA-SIP),and the methane and ammonia oxidation under various N levels was studied.【Result】The results showed that methane-oxidizing activity was stimulated by low N while it was suppressed by high N application.Contrarily,the nitrification activity was stimulated by both low and high N addition.The Methylobacter lineage of methane-oxidizing bacteria(MOB)were the active players in methane oxidation,while nitrifying communities dominated by Nitrosospira lineage of AOB and Nitrospira-like nitrite-oxidizing bacteria(NOB)were the active players in nitrification.Also,the network analysis unraveled significant negative relationships between active Methylobacter MOB and Nitrosospira AOB/Nitrospira NOB,which suggested competitive interactions between active methanotrophs and nitrifiers in grassland soils.【Conclusion】The interactions between active methanotrophs and nitrifiers can be affected by N levels.Our results provide theoretical support for regulating CH_(4) sinks and N_(2)O sources of grassland soils and for greenhouse gas mitigation.

关 键 词：氮素水平 甲烷氧化 硝化作用 氨氧化细菌 甲烷氧化细菌 微生物相互作用 草原土壤 

分 类 号：S154.36[农业科学—土壤学]