黄土-古土壤原核生物群落对古气候变化的响应  

Response of prokaryotic community in loess-paleosol to paleoclimate change

作　　者：刘秀花[1,2] 孙钰涵 卢杰 刘小康 马延东 贺屹 胡安焱[1,2] LIU Xiuhua;SUN Yuhan;LU Jie;LIU Xiaokang;MA Yandong;HE Yi;HU Anyan(School of Water and Environment,Chang’an University,Xi’an 710054,Shaanxi,China;Key Laboratory of Groundwater and Ecological Effects in Arid Areas,Ministry of Education,Xi’an 710054,Shaanxi,China;Shaanxi Provincial Land Engineering Construction Group Limited Liability Company,Baoji 721004,Shaanxi,China;River and Lake Reservoir and Immigrant Work Center,Water Conservancy Bureau of Yulin,Yulin 719000,Shaanxi,China;Key Laboratory of State Forestry Administration on Soil and Water Conservation and Ecological Restoration of Loess Plateau,Shaanxi Academy of Forestry,Xi’an 710082,Shaanxi,China)

机构地区：[1]长安大学水利与环境学院,陕西西安710054 [2]旱区地下水与生态效应教育部重点实验室,陕西西安710054 [3]陕西省土地工程建设集团有限责任公司,陕西宝鸡721004 [4]榆林市水利局河湖水库与移民工作中心,陕西榆林719000 [5]陕西省林业科学研究院国家林业局黄土高原水土保持与生态恢复重点实验室,陕西西安710082

出　　处：《微生物学报》2024年第6期1800-1823,共24页Acta Microbiologica Sinica

基　　金：国家自然科学基金(42372288);陕西林业科技创新专项(SXLK2022-06-3);中央高校基本科研业务费专项资金(300102292904)。

摘　　要：【目的】黄土-古土壤序列是记录第四纪气候环境变化的良好载体,其内部的土壤微生物特征是蕴含土壤环境变化的重要信息。由于黄土与古土壤成壤环境的气候差异,微生物群落结构特征可能会有不同的响应,但针对该问题的研究还十分有限。【方法】选择任家坡(R)和九州台(J)两地黄土(RL和JL)-古土壤(RS和JS)序列,运用高通量测序技术和线性判别分析效应大小(linear discriminant analysis effect size,LEfSe)识别土壤原核生物群落结构和类群差异,基于原核生物分类单元功能注释(functional annotation of prokaryotic taxa,FAPROTAX)数据库进行群落功能预测,以及利用Mantel test探讨影响土壤原核生物群落稳定的环境因子。【结果】土壤中碳氮营养物质与气候变化的代用指标磁化率、Rb/Sr变化趋势一致,含量整体表现为古土壤(RS和JS)高,对应的黄土(RL和JL)低,这一特征在任家坡古土壤(RS)中尤为显著;在同一气候时期,九州台较任家坡更为干冷,并且九州台古土壤沉积阶段也受到较强冬季风的影响,使其气候冷干与暖湿转变呈渐变型。原核生物群落结构中酸杆菌门(Acidobacteria)、泉古菌门(Crenarchaeota)、绿弯菌门(Chloroflexi)等具有嗜热嗜温性质的细菌和古菌在任家坡黄土-古土壤(RL和RS)中丰度较高,芽单胞菌门(Gemmatimonadetes)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、广古菌门(Euryarchaeota)、异常球菌-栖热菌门(Deinococcus-Thermus)等耐旱、适宜极端环境中生存的细菌和古菌在九州台黄土-古土壤中(JL和JS)丰度较高。同时,生命产能、氮、锰、铁、氯元素循环相关功能基因在任家坡古土壤(RS)中表达量最高,而碳、氢、硫元素循环相关功能基因在任家坡黄土(RL)中表达量最高。与任家坡相比,九州台原核生物群落具有物种多样性高、功能种类少的特点。Mantel test分析进一步表明,有机碳(soil organic carbon,SOC[Objective]Loess-paleosol sequence(LPS)is a good carrier recording the changes of Quaternary climate and environment,and the characteristics of soil microorganisms in it indicates important information about the changes of soil environment.Due to the climate difference between loess and paleosoil,the soil microbial community may have different responses in the structural characteristics.The research on this problem,however,is limited.[Methods]In this paper,the loess(RL and JL)-paleosol(RS and JS)sequences in Renjiapo(R)and Jiuzhoutai(J)were selected,and high-throughput sequencing and linear discriminant analysis effect size(LEfSe)were employed to gain insights into the community structure and group differences of soil prokaryotes.Furthermore,functional annotation of prokaryotic taxa(FAPROTAX)was used to predict the community function,and the Mantel test was carried out to identify the environmental factors affecting the community stability of soil prokaryotes.[Results]The carbon and nitrogen in soil showed changes consistent with the magnetic susceptibility and Rb/Sr ratio,the alternative indicators of climate change.The content of carbon and nitrogen was high in the paleosol(RS and JS,especially in RS)and low in the corresponding loess(RL and JL).In the same climate era,Jiuzhoutai was drier and colder than Renjiapo.The paleosol deposition stage in Jiuzhoutai was affected by strong winter monsoon,which ultimately led to the gradual change from the dry-cold to wet-warm climate.In the prokaryotic community,thermophilic or mesophilic bacteria and archaea,such as Acidobacteria,Crenarchaeota,and Chloroflexi,were abundant in RL and RS,while those with tolerance to drought and extreme environments,such as Gemmatimonadetes,Actinobacteria,Firmicutes,Euryarchaeota,and Deinococcus-Thermus,had high abundance in JL and JS.The functional genes related to energy source and nitrogen,manganese,iron,and chlorine cycling had the highest expression levels in RS,while those involved in carbon,hydrogen,and sulfur cycling showed the hi

关 键 词：黄土-古土壤序列 原核生物群落 结构 功能 古气候 

分 类 号：S154.3[农业科学—土壤学]