季节性河流好氧氨氧化微生物的时空分布及网络互作研究——以漕河为例  

Spatiotemporal distribution and network interactions of aerobic ammonia-oxidizing microorganisms in seasonal rivers:A case study of the Cao River

作　　者：肖满义 王衫允[1] 李祎飞 余杰 秦瑜 姜丽萍 邹华 祝贵兵[1] XIAO Manyi;WANG Shanyun;LI Yifei;YU Jie;QIN Yu;JIANG Liping;ZOU Hua;ZHU Guibing(Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085;Jiangsu Key Laboratory of Anaerobic Biotechnology,School of Environmental and Civil Engineering,Jiangnan University,Wuxi 214122;Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment,Suzhou University of Science and Technology,Suzhou 215009)

机构地区：[1]中国科学院生态环境研究中心,中国科学院饮用水科学与技术重点实验室,北京100085 [2]江南大学环境与土木工程学院,江苏省厌氧生物技术重点实验室,无锡214122 [3]苏州科技大学,江苏省水处理技术与材料协同创新中心,苏州215009

出　　处：《环境科学学报》2023年第12期238-249,I0006,共13页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.42177063,92251304,42107418);中国科学院青年创新促进会项目;中国科学院生态环境研究中心“双碳”项目(No.RCEES-TDZ-2021-20)。

摘　　要：好氧氨氧化是硝化过程的关键步骤,第3种好氧氨氧化微生物—完全氨氧化细菌(Complete Ammonia Oxidizer,Comammox)的发现进一步完善了人们对硝化过程的认识.Comammox被发现广泛分布于自然和人工生态系统,但其在季节性河流的时空分布及生态网络互作关系的研究较少.本研究应用实时荧光定量q PCR、宏基因组测序和氨单加氧酶功能基因(amo A)特异性分析等方法,探究了不同水文时期漕河岸边带和开阔水体表层沉积物中Comammox等好氧氨氧化微生物的丰度、分布、群落结构、共生模式及关键环境因子.结果表明,Comammox的amo A基因丰度(106~108copies·g-1)最高,显著高于氨氧化古菌(Ammonia-oxidizing Archaea,AOA)和氨氧化细菌(Ammonia-oxidizing Bacteria,AOB),与宏基因组分析得到相对丰度结果一致.Spearman相关性和冗余分析表明,含水率(Moisture content)是Comammox等好氧氨氧化微生物丰度的关键影响因子.生物多样性和主坐标分析(Principle Coordinate Analysis,PCo A)表明,Comammox等好氧氨氧化微生物的群落结构具有明显的时间异质性,其α多样性在丰水期高于枯水期.季节性河流沉积物中Comammox菌主要为Nitrospira sp.SCGC AG-212-E16,相对丰度可达21.4%±6.4%;其次为Nitrospira sp.SG-bin-1、Candidatus Nitrospira nitrificans和Candidatus Nitrospira nirosa.结合分子生态网络分析进一步发现,Nitrospira sp.SCGC AG-212-E16是Comammox群落的关键菌种,起主要的群落内部连接功能.本研究揭示了Comammox细菌在河流生态系统中的高丰度和时空异质性,对进一步研究Comammox等好氧氨氧化微生物在硝化过程中的贡献以及河流氮污染的治理具有重要意义.Aerobic ammonia oxidation is a key step in nitrification process.The discovery of the third aerobic ammonia-oxidizing microorganism—complete ammonia oxidizers(Comammox bacteria)has further improved our understanding of nitrification process.Comammox bacteria has been reported to be widely distributed in natural and artificial ecosystems,however,its spatiotemporal distribution and ecological network interactions in seasonal rivers remain limited.In this study,the abundance,distribution,community,interactions and key environmental factors of aerobic ammonia-oxidizing microorganisms were investigated in riparian zone and open water sediments in Cao River by using the real-time quantitative PCR and metagenomic sequencing analyses.The results indicate that Comammox has the highest abundance(106~108 copies⸱g-1),which is significantly higher than ammonia-oxidizing archaea(AOA)and ammonia-oxidizing bacteria(AOB),in consistence with the results of relative abundance obtained from metagenomic analysis.Both spearman correlation and redundancy analyses indicated that moisture content is a critical factor,influencing the abundances of Comammox,AOA and AOB.Principal coordinate axis analysis showed that the community of aerobic ammonia-oxidizing microorganisms has a significant temporal heterogeneity,with higherαdiversity in rainy season compared to dry season.Nitrospira sp.SCGC AG-212-E16 was the dominated Comammox bacteria with a relative abundance of up to 21.4%±6.4%,following by Nitrospira sp.SG-bin-1,Candidatus Nitrospira nitrificans and Candidatus Nitrospira nirosa.Furthermore,based on the molecular ecological network analysis,Nitrospira sp.SCGC AG-212-E16 was also found to be the key connecter among the Comammox bacteria and played a major role in the internal connectivity of the community.This study revealed high abundance and spatiotemporal heterogeneity of Comammox bacteria in Cao River,highlighting their potential role in the nitrification processes and nitrogen pollution treatment in the seasonal river ecosyst

关 键 词：完全氨氧化 氨氧化细菌 氨氧化古菌 岸边带 氨单加氧酶功能基因 宏基因组 

分 类 号：X172[环境科学与工程—环境科学]