Shifts in core taxa drive microbial community stability and soil multifunctionality during alpine ecological restoration

Abstract Soil microbial communities, particularly core taxa that serve as hubs within co‐occurrence networks, are hypothesized to be fundamental to ecosystem stability and multifunctionality. However, empirical evidence linking the dynamics of core taxa to microbial community stability and soil functional recovery is less provided during ecological restoration. Herein, we conducted a 4‐year restoration experiment in an alpine region influenced by infrastructure development. Soils were sampled from bare land, three revegetation types (grass, shrub–grass and tree–shrub–grass) and undisturbed natural land. By integrating identification of core taxa (based on keystone nodes, habitat specialists and shared taxa) and measurements of soil carbon, nitrogen and phosphorus cycling functions, we assess ecological restoration outcomes. The results indicated that a simple and fragile microbial network dominated by aerobic bacterial taxa (e.g. Ellin6067, Sphingomonas, Rhodanobacter ) was exhibited in bare land. Following vegetation establishment, microbial network complexity increased markedly, with fungal taxa (e.g. Humicola, Didymella ) assuming central roles and metabolic strategies shifting towards facultative metabolism. The resistance and resilience of the soil microbial community increased in revegetated plots, as evidenced by a significantly reduced Bray–Curtis dissimilarity relative to bare land. Core microbial taxa exhibited strong negative correlations with soil multifunctionality and nutrient cycling functions, suggesting a hysteresis effect and the reconstruction of core microbes because resources are invested in building microbial network stability rather than immediately promoting soil functions during the early stage of ecological restoration. Synthesis and applications . Our findings demonstrate that core microbes play a pivotal role in reconstituting soil microbial networks and driving functional recovery during ecological restoration. We recommend integrating microbial indicators, particularly the successional status of core bacterial and fungal taxa, into monitoring and assessment frameworks for alpine restoration projects. Furthermore, tailoring plant communities to facilitate beneficial microbial shifts could accelerate the recovery of ecosystem multifunctionality.