Soil resources mediate the strength of species but not trait convergence across grassland restorations

Ecological restoration is notoriously unpredictable because similar actions can result in different outcomes. Outcomes can also differ for species and functional components of communities depending on how restoration actions and abiotic conditions alter community assembly trajectories. Quantifying variation in community trajectories across restorations for both species and traits is rare, but can help to resolve underlying assembly processes and refine strategies to maximize restoration success. We quantified the importance of soil resources, seed mix richness, and prescribed fire for variation in plant species and functional trait trajectories over six years across 20 restored tallgrass prairies in the midwestern United States. We predicted stronger convergence for traits than species, with species and trait compositions converging more across restorations on resource-poor soils and with frequent fires due to stronger abiotic filtering. In contrast, we predicted species and trait compo...