Over the past 160 years,shrubs have expanded globally,significantly altering native ecosystem structures,functions,and services.However,a comprehensive bibliometric perspective on shrub encroachment remains underdevel...Over the past 160 years,shrubs have expanded globally,significantly altering native ecosystem structures,functions,and services.However,a comprehensive bibliometric perspective on shrub encroachment remains underdeveloped,and a holistic research framework is lacking to understand the evolution,current state,and emerging research frontiers.To address this,we conducted a bibliometric analysis and literature review using the R software package,based on the Web of Science Core Collection citation database.Keyword analysis revealed that research has focused on various grassland types,soil nutrients,climate change,and plant communities.Thematic mapping identified key themes,including influencing factors,feedback mechanisms,invasion processes,ecological consequences,shrub management,and quantitative monitoring.Basic themes encompass shrub encroachment,dynamics,fire,grazing,and climate change while emerging themes include decomposition,microbial biomass,and ecosystem function.We synthesized eight key factors driving shrub encroachment:atmospheric CO_(2)concentration,global warming,changes in rainfall patterns,atmospheric nitrogen deposition,topography,soils,herbivory,fire suppression,and land use change.The feedback mechanisms of shrub encroachment,driven by exogenous and maintained by endogenous factors,were categorized into three stages:seed dispersal,colonizing and establishment,and diffusion.Shrub encroachment also impacts ecosystem services,including provisioning(e.g.,forage productivity),regulating(e.g.,hydrological regulation),and supporting(e.g.,carbon sequestration and biodiversity).We also summarized four main approaches to shrub management:burning,biological,chemical,and physical removal.The connections between the ecosystem services affected by shrub encroachment and the United Nations Sustainable Development Goals(SDGs)were highlighted to achieve synergies across multiple objectives.We emphasize the importance of quantification and monitoring in understanding the causes,consequences,and management of shrub encroachment.We advocate for long-term,location-based,and globally networked experiments and recommend the integration of new technologies,such as LiDAR,drones,and artificial intelligence,into shrub encroachment research.In conclusion,our study provides a comprehensive dataset and research framework for scholars studying shrub encroachment,aiming to deepen our understanding of this ecological process.展开更多
基金supported by the National Natural Science Foundation of China(32401433)National Key Research and Development Program of China(2023YFD1501001)+2 种基金the Natural Science Foundation of Ningxia(2024AAC03127)the Postdoctoral Fellowship Program of CPSF(GZC20232621)the Ningxia Higher Education Institutions First-Class Discipline Construction Project(NXYLXK2017A01).
文摘Over the past 160 years,shrubs have expanded globally,significantly altering native ecosystem structures,functions,and services.However,a comprehensive bibliometric perspective on shrub encroachment remains underdeveloped,and a holistic research framework is lacking to understand the evolution,current state,and emerging research frontiers.To address this,we conducted a bibliometric analysis and literature review using the R software package,based on the Web of Science Core Collection citation database.Keyword analysis revealed that research has focused on various grassland types,soil nutrients,climate change,and plant communities.Thematic mapping identified key themes,including influencing factors,feedback mechanisms,invasion processes,ecological consequences,shrub management,and quantitative monitoring.Basic themes encompass shrub encroachment,dynamics,fire,grazing,and climate change while emerging themes include decomposition,microbial biomass,and ecosystem function.We synthesized eight key factors driving shrub encroachment:atmospheric CO_(2)concentration,global warming,changes in rainfall patterns,atmospheric nitrogen deposition,topography,soils,herbivory,fire suppression,and land use change.The feedback mechanisms of shrub encroachment,driven by exogenous and maintained by endogenous factors,were categorized into three stages:seed dispersal,colonizing and establishment,and diffusion.Shrub encroachment also impacts ecosystem services,including provisioning(e.g.,forage productivity),regulating(e.g.,hydrological regulation),and supporting(e.g.,carbon sequestration and biodiversity).We also summarized four main approaches to shrub management:burning,biological,chemical,and physical removal.The connections between the ecosystem services affected by shrub encroachment and the United Nations Sustainable Development Goals(SDGs)were highlighted to achieve synergies across multiple objectives.We emphasize the importance of quantification and monitoring in understanding the causes,consequences,and management of shrub encroachment.We advocate for long-term,location-based,and globally networked experiments and recommend the integration of new technologies,such as LiDAR,drones,and artificial intelligence,into shrub encroachment research.In conclusion,our study provides a comprehensive dataset and research framework for scholars studying shrub encroachment,aiming to deepen our understanding of this ecological process.
