天津农田包气带氮循环微生物群落特征及分子生态网络分析  

Characteristics and molecular ecological network analysis of nitrogen cycling microbial communities at farmland unsaturated zone in Tianjin

作　　者：向兰欣 彭潇贤 薛冬梅[1] XIANG Lanxin;PENG Xiaoxian;XUE Dongmei(Tianjin Key Laboratory of Water Resources and Environment,Tianjin Normal University,Tianjin 300387,China;School of Geography and Environmental Science,Tianjin Normal University,Tianjin 300387,China)

机构地区：[1]天津师范大学天津市水资源与水环境重点实验室,天津300387 [2]天津师范大学地理与环境科学学院,天津300387

出　　处：《天津师范大学学报（自然科学版）》2024年第4期19-25,共7页Journal of Tianjin Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(41973017);天津市自然科学基金重点资助项目(19JCZDJC40700)。

摘　　要：土壤包气带硝酸盐累积会造成地下水氮污染,对生态和人类健康产生不利影响.为探究土壤包气带硝酸盐削减与微生物群落的关系,以天津农田土壤包气带(0~3 m)为研究对象,通过测定土壤理化性质,借助16S rRNA高通量测序,分析微生物群落特征并构建土壤氮循环微生物分子生态网络.结果显示:天津农田土壤中奇古菌门(Thaumarchaeota)和变形菌门(Proteobacteria)微生物群落相对丰度最高,微生物群落组成与土壤pH值、铵盐含量、亚硝酸盐含量呈现显著相关性.氮循环分子生态网络中出现氨氧化古菌、氨氧化细菌、亚硝酸盐氧化菌、反硝化菌、厌氧氨氧化菌、硝酸盐异化还原为铵细菌以及NC10门细菌等.反硝化菌群是硝酸盐削减的主要驱动力,并与以氨氧化古菌、亚硝酸盐氧化菌、硝酸盐异化还原为铵细菌为代表的其他参与氮循环的微生物群落之间形成竞争为主的相互关系,使微生物群落保持稳定性.同时,群落之间的合作关系促进了氮循环转化,进而保证硝酸盐削减的可持续性.Accumulation of nitrate in unsaturated zone of soil can cause groundwater nitrogen pollution,which demonstrates serious impact on ecology and human health.To investigate the relationship between nitrate reduction and microbial communi-ties in unsaturated zone,soil physico-chemical properties were measured,and 16S rRNA high-throughput technology and molecular ecological network were used to analyze the structure and characteristics of the nitrogen cycling microbial communi-ties in the unsaturated zone,where soil samples(0-3 m)were collected from farmland in Tianjin.The results showed that Thau-marchaeota and Proteobacteria were the dominant phylum,and microbial communities were significantly correlated with pH value,ammonium content and nitrite content.Ammonia oxidizing archaea,ammonia oxidizing bacteria,nitrite oxidizing bac-teria,denitrifying bacteria,anaerobic ammonium oxidation bacteria,dissimilatory nitrate reduction to ammonium bacteria,and NC10 phylum bacteria appeared in the molecular ecological network of soil microbial communities for nitrogen cycling.Denitrifying bacteria are the main driver of nitrate reduction.The competitive relationship between denitrifying bacteria and ammonia oxidizing archaea,nitrite oxidizing bacteria and dissimilatory nitrate reduction to ammonium bacterial communities maintained the microbial communities stable,while the cooperative relationship between the communities promoted the nitro-gen cycle,thus ensures the sustainability of nitrate reduction.

关 键 词：包气带 氮循环 微生物群落特征 微生物分子生态网络 

分 类 号：Q938.1[生物学—微生物学] X172[环境科学与工程—环境科学]