不同林龄桉树根际及非根际土壤微生物群落结构及功能  

Composition and function of soil microbial community in rhizosphere soil and bulk soil of Eucalyptus plantation across different stand ages

作　　者：朱媛 王亚鑫 覃方锉 孟森 王胜坤[1] 陆俊锟[1] ZHU Yuan;WANG Yaxin;QIN Fangcuo;MENG Sen;WANG Shengkun;LU Junkun(Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,China;Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]中国林业科学研究院热带林业研究所,广州510520 [2]南京林业大学,南京210037

出　　处：《生态学报》2024年第18期8409-8422,共14页Acta Ecologica Sinica

基　　金：国家重点研发计划课题(2023YFD2201005);国家自然科学基金青年基金(32101510);广东省基础与应用基础研究基金(2022A1515010413);中国林业科学研究院基本科研业务费项目(CAFYBB2023MA007)。

摘　　要：桉树(Eucalyptus spp.)是最重要的速生人工林树种之一,但其导致的不良生态效应使其备受争议。桉树对土壤微生物群落的影响尚缺乏研究。以2、7、12、17和22年的桉树人工林为研究对象,利用宏基因组测序技术探究根际和非根际微生物群落结构、多样性及功能对桉树林龄的响应。结果表明:土壤理化性质及多样性随林龄呈现先降低后升高的趋势。根际土真菌群落多样性在12年最低,非根际土细菌、根际及非根际土古菌群落均在7年最低。不同林龄间桉树根际及非根际土的微生物群落组成均存在显著差异,但并未改变真菌群落优势菌属(根孢囊霉属,Rhizophagus)。然而,根际土的细菌与古菌群落优势菌属与非根际土存在显著差异,根际土的优势细菌菌属分别为慢生根瘤菌属(Bradyrhizobium)及拟杆菌属(Bacteroides),优势古菌菌属为Candidatus-Nitrosotalea属及甲烷粒菌属(Methanocorpusculum)。真菌对硝态氮,细菌、古菌群落α多样性及群落组成对pH有较大响应。此外,古菌α多样性及群落组成对有效磷有较大响应。真菌、细菌、古菌的功能在根际及非根际间存在显著差异,且细菌群落的变异最大。研究揭示了不同林龄桉树土壤微生物群落的动态变化规律,为桉树人工林提质增效、多功能经营提供理论依据。Eucalyptus is one of the most important fast-growing tree species for afforestation with economically significance.But its adverse ecological effects of successive planting of Eucalyptus plantation have caused controversy,including soil degradation,reduced plant diversity and stand productivity.To ensure their sustainability remains an important topic in forestry.However,our understanding about the effects of Eucalyptus on composition and functions of soil microbial community remain poorly understood.Understanding these impacts is crucial to provide a basis for silvicultural management to address the adverse ecological effects on Eucalyptus plantations.In order to characterize the dynamics of different microbial categories,such as fungi,bacteria and archaea,a chronosequence of Eucalyptus plantations of 2,7,12,17,and 22 years were selected.The metagenomic sequencing was used to measure the response of microbial community structure,diversity,and function in both rhizosphere and bulk soil of Eucalyptus plantations across different ages.The results suggested that there was a pattern of initial decline followed by an upswing in soil physicochemical properties and diversity with stand age.At 12 years,the fungal communities in rhizosphere soil showed the lowest diversity.Meanwhile,both archaea communities in the rhizosphere and bulk soil,as well as bacteria communities in the bulk soil,had their lowest diversity at 7 years,respectively.The composition of microbial communities between rhizosphere and bulk soil significantly differed across different stand ages.Interestingly,stand age did not induce significant shifts in the dominant fungal genus between rhizosphere and bulk soil,which was identified as Rhizophagus.However,the significant changes in the dominant genera of both bacterial and archaeal in rhizosphere soil were detected.The prevailing bacterial groups were identified as Bradyrhizobium and Bacteroides,while the dominant archaea were identified as Candidatus-Nitrosotalea and Methanocorpusculum.The nitrate nitro

关 键 词：桉树 林龄 土壤微生物群落 多样性 宏基因组测序 

分 类 号：S714.3[农业科学—林学] S792.39