酸性红壤有机碳组成与微生物种群特征的相关性研究  

The effect of soil organic carbon composition on microbial population characteristics in acidified red soil area

作　　者：龙超 刘仁绿 尹丽[2] 宋勇生[2] 贺根和[2] 刘祖文 LONG Chao;LIU Renlu;YIN Li;SONG Yongsheng;HE Genhe;LIU Zuwen(School of Civil and Surveying&Mapping Engineering,Jiangxi University of Science and Technology,Ganzhou 341000;School of Life Sciences,Jinggangshan University,Ji′an 343009;School of Hydraulic&Ecological Engineering,Nanchang Institute of Technology,Nanchang 330099)

机构地区：[1]江西理工大学土木与测绘工程学院,赣州341000 [2]井冈山大学生命科学学院,吉安343009 [3]南昌工程学院水利与生态工程学院,南昌330099

出　　处：《环境科学学报》2024年第1期377-388,共12页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.41867032,22366020);江西省自然科学基金项目(No.20202ACBL203011,20232BAB213071)。

摘　　要：微生物在土壤碳周转中起关键驱动作用,南方红壤区土壤由于酸化严重,导致土壤微生物丰度较低,且碳汇不足.在土壤酸化背景下不同组分有机碳与微生物多样性之间的关联及影响机制尚不清楚,极大限制了红壤碳汇潜力的研究.本文通过对4种不同覆盖植被(杉木林、针阔混交林、竹林和茶油林)土壤碳组分含量和微生物多样性特征进行分析,结果表明:杉木林(21.9 g·kg^(-1))和针阔混交林(20.57 g·kg^(-1))土壤总有机碳(SOC)含量均高于竹林(9.95 g·kg^(-1))和茶油林(12.6 g·kg^(-1)),溶解性有机碳(DOC)与微生物量碳(MBC)含量与SOC呈相同分布趋势,然而易氧化有机碳(ROC)、总氮(TN)和总磷(TP)在不同植被间无显著差异.4种土壤中变形菌(Proteobacteria)、放线菌(Actinobacteriota)、酸杆菌(Acidobacteriota)、绿弯菌(Chloroflexi)和疣微菌(Verrucomicrobiota)在细菌种群中占据优势生态位,优势细菌群落分布在不同土壤中无显著差异;土壤中分布较多的真菌为子囊菌(Ascomycota)、担子菌(Basidiomycota)和被孢霉菌(Mortierellomycota),Basidiomycota在竹林和针阔混交林土壤中占优势,而Ascomycot是茶油林和杉木林土壤中相对丰度最高的真菌群落.Spearman相关性分析表明,Actinobacteriota、Chloroflexi和Verrucomicrobiota种群丰度与活性有机碳(AOC)呈显著相关性(p<0.05),Ascomycota和Basidiomycota与稳定有机碳组分矿物结合态有机碳(MOC)和生物化学稳定有机碳(BROC)呈显著相关性(p<0.05),细菌群落对活性有机碳组分的依赖性强,真菌群落与稳定有机碳组分关联性较大.冗余分析(RDA)结果表明细土壤特性对菌群落丰度影响大小为pH>DOC>AOC>SOC;真菌为SOC>SMC>MBC>BROC,在红壤中真菌较细菌有更强的耐酸能力.FAPROTAX和FUNGuild预测表明,主要的功能菌群丰度在各分组间均有显著差异,纤维素分解、尿素分解、芳香族化合物降解、固氮和硝酸盐还原是主要的碳氮转化功能�Microorganisms play a key role in driving soil carbon turnover.However,soil acidification in the southern red soil region reduces microbial abundance and carbon sink capacity.The relationships and mechanisms among different organic carbon components,microbial diversity and soil acidification remain unclear,limiting the assessment of carbon sink potential of red soil.Here,we analyzed soil carbon content and microbial diversity of four different vegetation types(Cunninghamia lanceolata,Coniferous and broad mixed forest,Bamboo forest,and Camellia forest)in this region.The results showed that:(1)The soil total organic carbon(SOC)content of Cunninghamia lanceolata(21.9 g·kg^(-1))and Coniferous and broad mixed forest(20.57 g·kg^(-1))was higher than that of Bamboo forest(9.95 g·kg^(-1))and Camellia forest(12.6 g·kg^(-1)).(2)The contents of dissolved organic carbon(DOC)and microbial biomass carbon(MBC)followed the same pattern as SOC,but the contents of readily oxidized organic carbon(ROC),total nitrogen(TN)and total phosphorus(TP)did not differ significantly among vegetation types.The bacterial population in the four soil species was dominated by Proteobacteria,Actinobacteriota,Acidobacteriota,Chloroflexi and Verrucomicrobiota.The distribution of dominant bacterial communities did not differ significantly among different soils.The most prevalent fungi in the soil were Ascomycota,Basidiomycota and Mortierellomycota,with Basidiomycota being dominant in the Bamboo forest and Coniferous and broad mixed forest soils.Ascomycota was the most abundant fungal community in the Camellia forest and Cunninghamia lanceolata soils.Spearman correlation analysis revealed that the abundance of Actinobacteriota,Chloroflexi and Verrucomicrobiota was significantly correlated with active organic carbon(AOC)(p<0.05),while Ascomycota and Basidiomycota were significantly correlated with mineral-bound organic carbon(MOC)and biochemically stable organic carbon(BROC)(p<0.05).The bacterial community was strongly dependent on active organic carb

关 键 词：酸性红壤 土壤有机碳 高通量测序 微生物多样性 冗余分析 功能预测 

分 类 号：X172[环境科学与工程—环境科学]