北京林业大学学报2026，Vol.48Issue(8)：12-24,13.DOI:10.12171/j.1000-1522.20260049
橡胶林恢复过程中土壤固氮微生物的多样性格局与构建机制
Diversity patterns and assembly mechanisms of soil diazotrophic community following the restoration of rubber monocultures
摘要
Abstract
[Objective]The rapid expansion of monoculture rubber plantations in tropical regions has led to severe soil degradation and ecosystem nitrogen limitation.Biological nitrogen fixation plays a crucial role in alleviating nutrient constraints in degraded systems;however,the dynamics and assembly mechanisms of its key functional microbial communities during rubber plantation restoration remain poorly understood.This study aimed to reveal the diversity patterns and assembly mechanisms of soil diazotrophic communities during restoration and to compare the differences between natural restoration and human-assisted restoration strategies.[Method]Using a space-for-time substitution approach,four forest types were investigated in Xishuangbanna,China:rubber monoculture(RM),naturally restored forest(NF),artificially restored forest(AF),and mature tropical rainforest(MF).Here,RM represents a degraded forest,while NF and AF represent regenerated forests under different restoration strategies,and MF serves as a reference.Based on high-throughput sequencing of the nifH gene,we classified different ecological groups according to abundance thresholds,and combined β diversity decomposition with community assembly models to systematically analyze the shifts in diversity patterns and assembly mechanisms of soil diazotrophic communities during rubber plantation restoration.[Result](1)The community structures of diazotrophs in restored forests(NF and AF)were significantly different from both RM and MF,with a clear divergence observed between NF and AF;(2)β diversity decomposition revealed that species turnover was the dominant process driving compositional variation among diazotrophic communities,and conditionally rare taxa(CRT,abundance<1%with partial samples<0.01%)and absolutely rare taxa(ART,abundance<0.01%in all samples)were highly consistent with the turnover pattern of the overall community,suggesting that these taxa might be important contributors to the high turnover of the overall community;(3)The assembly of diazotrophic communities is predominantly governed by stochastic processes(ecological drift and dispersal limitation),with variations observed across different restoration strategies and ecological groups.Specifically,the contribution of stochastic processes increased in AF but decreased in NF for overall taxa,CRT,and ART,while it decreased for dominant taxa in both AF and NF.pH,total soil carbon(TC),and total soil nitrogen(TN)were identified as key environmental factors driving the differentiation of different ecological groups,with CRT exhibiting stronger environmental sensitivity than other groups,indicating their potential as environmental indicators.[Conclusion]Restoration of rubber monocultures drives the restructuring of soil diazotrophic communities,with assembly mechanisms exhibiting differentiated responses.Our findings suggest that restoration practices should pay attention to the long-term impacts of different restoration strategies on community assembly processes,and we recommend adopting an integrated restoration strategy of"initial artificial facilitation followed by natural succession"to balance recovery efficiency with long-term ecosystem stability and resilience.This study reveals the differential response characteristics of diazotrophic community assembly during rubber plantation restoration,providing a scientific basis for function-oriented restoration of degraded ecosystems.关键词
橡胶林恢复/生物固氮/β多样性分解/群落构建/随机过程/生态类群分化Key words
rubber monoculture restoration/biological nitrogen fixation/β diversity decomposition/community assembly/stochastic processes/ecological group differentiation分类
农业科技引用本文复制引用
陈姿妍,宋亮,Sujan Balami,石贤萌..橡胶林恢复过程中土壤固氮微生物的多样性格局与构建机制[J].北京林业大学学报,2026,48(8):12-24,13.基金项目
云南省重点研发计划(202403AC100028),中国科学院西双版纳热带植物园"十四五"科技创新规划项目(E3ZKFF7B),国家自然科学基金项目(32171529),云南省"兴滇英才支持计划"青年人才项目(YNWR-QNBJ-2020-066),"智慧云南"计划(202403AM140016),云南省"彩云博士后计划"创新支持项目. （202403AC100028）
