摘要
[目的]研究桉树人工林土壤理化性质、土壤固氮微生物多样性和群落结构特征,为探究多代萌芽桉树人工林土壤微生态提供理论依据。[方法]以不同代次(1代、2代、3代)土壤作为研究对象,以天然林为对照,采用化学分析和高通量测序技术,对土壤化学性质、固氮微生物nifH基因多样性和群落结构进行分析。[结果]不同代次桉树人工林土壤化学性质与天然林存在显著差异,且根际和非根际土壤的pH值、含水量、养分含量表现出代次差异;固氮微生物nifH基因丰度和群落多样性在不同代次根际和非根际土壤中存在显著差异,固氮微生物的丰富度和多样性在天然林中最高,1代林其次,3代林最低,土壤化学性质对其丰度和多样性具有显著影响。在门水平上,变形菌Proteobacteria属优势菌门,相对丰度为81.4%~98.5%。在属水平上,根际土壤以慢生根瘤菌属Bradyrhizobium为主,而非根际土壤则以未分类根瘤菌Unclassified_Rhizobiales为主。固氮基因nifH的群落结构中存在较高比例的未分类或其他基因,揭示土壤中存在丰富的未鉴定固氮微生物资源。[结论]多代萌芽桉树林土壤化学性质和固氮微生物群落结构及多样性随代次发生变化,天然林表现出较高的固氮微生物丰富度和多样性。在不同代次中,1代林能为桉树营造更适宜的微环境,其根际土壤中的固氮菌群落结构对桉树生长具有显著促进作用,从而促进了桉树的健康生长。
【Objective】This study aims to investigate the physicochemical properties of the soil,the diversity of nitrogen-fixing microorganisms,and the community structure characteristics in Eucalyptus plantations.The goal is to provide theoretical insights that will support further research into the soil microecology of multi-generational coppice Eucalyptus plantations.【Method】A natural forest was used as CK,and soils from different generations of Eucalyptus plantations(1st,2nd,and 3rd generations)were analyzed.Soil physicochemical properties were measured,and the diversity and community composition of nitrogen-fixing microorganisms were evaluated based on nifH gene sequencing.Microbial community structure was further analyzed using chemical methods and high-throughput sequencing technology.【Result】The soil physicochemical properties of Eucalyptus plantation showed significant differences compared to those of natural forests,with generational variations observed in rhizosphere and bulk soils,particularly in pH,moisture content,and nutrient levels.The abundance and diversity of nitrogen-fixing microorganisms,as determined by nifH gene analysis,exhibited significant generational differences.Natural forests had the highest abundance and diversity of nitrogen-fixing microorganisms,followed by first-generation plantation,and lowest in third-generation plantation.Soil physicochemical characteristics were found to exert a significant influence on the abundance and diversity of nitrogen-fixing microorganisms.At the phylum level,Proteobacteria were the most dominant group,with relative abundances ranging from 81.4%to 98.5%.At the genus level,Rhizosphere soils were predominantly occupied by the slow-growing genus Bradyrhizobium,while bulk soils were dominated by Unclassified_Rhizobiales.Furthermore,a substantial proportion of unclassified or unidentified genes was detected within the nifH gene community structure,indicating the potential presence of novel nitrogen-fixing bacterial species in the soil.【Conclusion】This study highlights that the soil physicochemical properties and the diversity and community structure of nitrogen-fixing microorganisms in multi-generational Eucalyptus plantations undergo significant changes with successive generations.Natural forests exhibited the highest richness and diversity of nitrogen-fixing microorganisms.Among the plantations,first-generation plantation stands provided a more favorable environment for Eucalyptus growth,characterized by a more beneficial nitrogen-fixing microbial community structure in the rhizosphere soil,which facilitated the healthy development of Eucalyptus trees.
作者
王金燕
马医生
何中玲
张志杰
周珍珍
粟国磊
姜成
赵文贵
王晓丽
王超
牛芸
WANG Jinyan;MA Yisheng;HE Zhongling;ZHANG Zhijie;ZHOU Zhenzhen;SU Guolei;JIANG Cheng;ZHAO Wengui;WANG Xiaoli;WANG Chao;NIU Yun(Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China,Ministry of Education,Southwest Forestry University,Kunming 650224,Yunnan,China;Key Laboratory of Forest Disaster Warning and Control Group in Yunnan Province,Southwest Forestry University,Kunming 650224,Yunnan,China;Engineering Technology Research Center of National Forestry and Grassland Administration on Southwest Landscape Architecture,Southwest Forestry University,Kunming 650224,Yunnan,China;Yunnan Yunjing Forestry and Pulp Mill Co.,Ltd,Pu’er 666400,Yunnan,China)
出处
《中南林业科技大学学报》
北大核心
2026年第1期92-103,共12页
Journal of Central South University of Forestry & Technology
基金
云南省教育厅科学研究基金项目(2023J0702)
云南省基础研究计划农业联合专项-面上项目(202301BD070001-088,202301BD070001-087)
“十四五”国家重点研发计划项目(2023YFD2201003)
云南省种子种业联合实验室项目(202205AR070001-22)
云南省大学生创新创业训练计划项目(20220455084)
西南林业大学博士科研启动项目(01102-110225027)。
关键词
桉树
多代萌芽
固氮微生物
NIFH基因
多样性
群落结构
eucalyptus
successive eucalyptus plantation
nitrogen-fixing microorganism
nifH gene
diversity
community structure
