Successional dynamics and driving factors of soil multitrophic communities along coal mine reclamation chronosequences in Shanxi, China

Introduction The recovery of multi-trophic soil communities is pivotal to ecological restoration of reclaimed coal mining areas, yet their succession and the driving mechanisms of soil multifunctionality (SMF) across regional gradients remain poorly understood. Methods We investigated three reclaimed coal mining areas in Shanxi Province, China-Pingshuo (north), Gujiao (central), and Qinshui (south)-using a 25-year chronosequence of Pinus tabuliformis plantations ( n = 75). Through high-throughput sequencing and integrated modeling (LASSO regression, Random Forest, PLS-PM), we characterized multi-trophic communities including bacteria, fungi, protists, and metazoans. Results Fungal and metazoan α-diversity declined from south to north, whereas bacterial communities showed no clear regional pattern. SMF showed pronounced regional variation, increasing with reclamation age in Pingshuo and Gujiao but declining in Qinshui. LASSO regression revealed regional variation in SMF drivers-from fungal community network degree (north) to bacterial network degree (central) to protist richness (south). PLS-PM suggested a parallel pattern from direct vegetation control to multi-trophic community-mediated regulation. Discussion Regional context shapes the regulatory strategy of SMF, while reclamation age modulates the rate and direction of recovery, jointly governing the trajectory of ecosystem multifunctionality during coal mine reclamation. These findings provide an empirical framework for region-specific adaptive ecological restoration in reclaimed coal mining areas.