放牧干扰下土壤微生物泛化种和特化种群落的研究OA

To reveal the response of microbial communities of generalized and specialized species to dif-ferent grazing intensities in mountain meadows in the middle section of the northern slope of Tianshan,the changing characteristics of generalized and specialized species in light grazing,heavy grazing,and control samples(with fenced-in meadows serving as the control)were studied,and the association of generalized and specialized species communities with soil factors under grazing interference was explored.The results showed that light grazing significantly enhanced both alpha and beta diversity of microbial generalists and specialists relative to heavy grazing.Proteobacteria,Actinobacteria,and Acidobacteriota dominated bacte-rial generalist and specialist communities,while Ascomycota,Basidiomycota,and Chytridiomycota were predominant in fungal communities across all grazing treatments.Co-occurrence network metrics(node number,edge number,average degree,and robustness)initially increased and subsequently declined with escalating grazing intensity,whereas vulnerability showed an inverse trend.The relative contribution of deterministic assembly processes to bacterial and fungal community assembley increased with grazing inten-sity;however,stochastic processes remained the dominant assembly mechanism.Functional prediction using Tax4Fun2 and FUNGuild revealed that grazing altered metabolic capabilities of bacterial functional groups and shifted the abundance profiles of fungal functional groups.Mantel tests and random forest analy-ses confirmed significant relationship between soil factors and microbial communities under grazing distur-bance,with soil variables exhibiting lower explanatory power for generalists than for specialists.