土壤学报2023，Vol.60Issue(6)：1776-1787,12.DOI:10.11766/trxb202111250641
稻田亚硝酸盐型甲烷厌氧氧化对大气CO2浓度缓增的响应
Response of Nitrite-dependent Anaerobic Methane Oxidation in Paddy Fields to Slow Increase of Atmospheric CO2 Concentration
摘要
Abstract
[Objective]The process of nitrite-dependent anaerobic methane oxidation(n-damo)catalyzed by Candidatus Methylomirabilis oxyfera(M.oxyfera)-like bacteria links both the carbon and nitrogen cycles,and has attracted great attention in recent years because of its potential role acting as a microbial methane sink.This process has been reported to be a novel pathway for controlling methane emissions from paddy ecosystems.Elevated atmospheric CO2 concentration can indirectly affect the structure and function of soil microbial communities.However,the response of n-damo to e[CO2]is poorly known.This study aims to explore the response of n-damo activity,and the community composition and abundance of M.oxyfera-like bacteria to e[CO2]in a paddy ecosystem.[Method]Here,ambient CO2 treatment(CK)and a slow increase of atmospheric CO2 treatment(EC:an increase of 40 μL·L-1 per year above CK until 160 μL·L-1)were set up based on the CO2 automatic control platform with open-top chambers.The stable isotope tracer experiment,quantitative PCR and high-throughput sequencing were employed to investigate the n-damo activity,abundance,diversity and community composition of M.oxyfera-like bacteria in paddy soils across three key rice growth stages(tillering,jointing and flowering stages)under different CO2 treatments.[Result]The results showed the occurrence of n-damo activity and the presence of M.oxyfera-like bacteria in the studied paddy soils.It was found that the n-damo activity ranged from 0.31 to 5.09 nmol CO2·g-1·d-1,and the abundance of M.oxyfera-like bacteria varied between 7.51×106 and 5.49×107 copies·g-1.Furthermore,EC treatment stimulated the n-damo activity and abundance of M.oxyfera-like bacteria,particularly at the jointing stage,in which the activity and abundance were increased by 137.9%and 96.0%,respectively.In addition,EC treatment significantly changed the community composition and diversity of M.oxyfera-like bacteria,and the diversity was increased under EC treatment.Correlation analyses showed that the soil dissolved organic carbon content,ammonium content,nitrate content and water content all had significant impacts on the community structure of M.oxyfera-like bacteria.The variations in soil dissolved organic carbon content and inorganic nitrogen content under EC treatment could probably cause the change of n-damo activity and the abundance of M.oxyfera-like bacteria.[Conclusion]Elevated atmospheric CO2 promoted the n-damo activity and M.oxyfera-like bacterial abundance and significantly changed the community structure of M.oxyfera-like bacteria in a paddy ecosystem.In addition,the changes of soil dissolved organic carbon content,inorganic nitrogen content and water content greatly affected the n-damo activity and community structure of M.oxyfera-like bacteria.Taken together,our results showed a positive response of n-damo to the slow increase of atmospheric CO2 concentration.关键词
大气CO2浓度缓增/亚硝酸盐型甲烷厌氧氧化/活性/群落结构/稻田土壤Key words
Slow increase of CO2 concentration/N-damo/Activity/Community structure/Paddy soil分类
生物科学引用本文复制引用
金靖昊,徐江兵,胡正华,黄翯宸,沈李东,田茂辉,刘心,杨王挺,杨钰铃,刘佳琦,任冰洁..稻田亚硝酸盐型甲烷厌氧氧化对大气CO2浓度缓增的响应[J].土壤学报,2023,60(6):1776-1787,12.基金项目
国家自然科学基金项目(41977037)、江苏省自然科学基金项目(BK20190092)和江苏省大学生创新创业训练计划项目(202110300110Y)共同资助Supported by the National Natural Science Foundation of China(No.41977037),the Natural Science Foundation of Jiangsu Province(No.BK20190092),and the Innovation and Entrepreneurship Training program for College students in Jiangsu Province(No.202110300110Y) （41977037）
