Plant colonization drives coupled Fe-mineral transformation, organic matter accumulation, and microbial community restructuring during early pedogenesis in Fe tailings

Pioneer plant colonization plays a role in converting Fe tailing into a functional soil-like substrate, contributing to the improvement of Fe tailing physicochemical properties and microbial ecological functions. However, the coupled biogeochemical mechanisms driving organic matter (OM) accumulation and mineral transformation during early pedogenesis remain poorly understood, hindering the optimization of tailings rehabilitation. This study investigated the early pedogenic processes mediated by pioneer plant colonization (perennial ryegrass, Lolium perenne L.) in Fe tailings amended with soil and corn straw. Through a controlled pot experiment, a combination of spectroscopic and diffraction techniques, dissolved organic matter (DOM) characterization and microbial DNA sequencing were employed to investigate the initial pedogenic processes of Fe tailings.