土地利用方式对紫色土全程及半程氨氧化微生物的影响  

Effects of Land Use Patterns on Complete and Incomplete Ammonia Oxidizer of Purple Soil

作　　者：石秀丽 马瑞 蒋先军[2] SHI Xiuli;MA Rui;JIANG Xianjun(College of Horticulture and Landscape Architecture,Southwest University,Chongqing 400715,China;College of Resources and Environment,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学园艺园林学院,重庆400715 [2]西南大学资源环境学院,重庆400715

出　　处：《西南大学学报(自然科学版)》2025年第4期70-79,共10页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金项目(42077035)。

摘　　要：探讨土地利用方式对紫色土全程氨氧化细菌(complete ammonia oxidizer,Comammox)、半程氨氧化微生物中氧化古菌(ammonia-oxidizing archaea,AOA)和氨氧化细菌(ammonia-oxidizing bacteria,AOB)的影响。在重庆紫色土区域采集林地、旱地及水田土壤,测定土壤硝化势和亚硝酸盐氧化势,分析土壤硝化活性;采用定量PCR技术分析Comammox、AOA及AOB的丰度,通过克隆测序技术分析Comammox两个分支clade A和clade B的群落组成并构建系统发育树。结果表明:Comammox与半程氨氧化微生物AOA、AOB类似,广泛分布于不同土地利用方式的紫色土中。不同土地利用方式的紫色土氨氧化微生物丰度存在差异,AOA amoA基因的丰度在林地中达到最大值,为8.26×107拷贝数/g,比旱地高出1个数量级;而AOB则更适应水田土壤环境,其丰度达到1.38×107拷贝数/g,分别是林地和旱地的38.4倍和3.4倍。全程氨氧化细菌的两个分支分别在林地和水田中达到最大丰度值,其中clade A在林地中的丰度达到1.85×108拷贝数/g,clade B在水田中的丰度达到1.48×107拷贝数/g。在紫色土中,全程氨氧化细菌归属于Nitrospira inopinata。Pearson相关性分析结果表明:AOB与土壤硝化势呈极显著正相关(p<0.01),clade A与硝化势呈显著负相关(p<0.05),clade B与亚硝酸盐氧化势呈显著正相关(p<0.05),说明AOB和全程氨氧化细菌可能是紫色土硝化作用的主要推动者。综合表明:土地利用方式是影响紫色土全程氨氧化细菌及半程氨氧化微生物生态位分化的重要因子。To better understand the effects of land use patterns on ammonia oxidizers of purple soil,the abundance and activity of Comammox(complete ammonia oxidizer),AOA(ammonia-oxidizing archaea)and AOB(ammonia-oxidizing bacteria)of purple soil from three land use patterns(upland,forest and paddy field)were investigated.Nitrification potential and nitrite oxidation potential were measured to analyze the activity of the soil ammonia oxidizers.Comammox,AOA and AOB abundances were analyzed by quantitative PCR,and the community composition of Comammox clade A and clade B was analyzed by clone sequencing and a phylogenetic tree was constructed.Results showed that similar to AOA and AOB,Comammox was widely distributed in purple soils of different land use patterns.The abundance of ammonia oxidizers in purple soil were different among land use patterns,with AOA amoA reaching a maximum abundance of 8.26×107 copies/g dry soil in forest soil,an order of magnitude higher than that of in upland soil.While AOB was better adapted to paddy field soil,with an abundance of 1.38×107 copies/g dry soil,which was 38.4 and 3.4 folds higher than that of in forest soil and upland soil,respectively.The most abundance of Comammox clade A and clade B was detected in forest and paddy field soils,respectively.The abundance of clade A and clade B reached 1.85×108 copies/g and 1.48×107 copies/g in forest land soil.Comammox detected in the soils of three land use patterns were all belonged to the Nitrospira inopinata cluster.Pearson correlation analysis showed a highly significant positive correlation between AOB and soil nitrification activity(p<0.01),while Comammox clade A was negatively correlated with potentials nitrification rates(p<0.05)and Comammox clade B was positively correlated with potentials nitrite oxidation rates(p<0.05),implying that AOB and Comammox may play an important role in the nitrification process of purple soil.Taken together,our results indicated that land use pattern was an important factor influencing the ecological niche

关 键 词：土地利用方式 紫色土 硝化作用 全程氨氧化细菌 生态位分化 

分 类 号：S154[农业科学—土壤学]