This study investigated the mechanisms underlying the differences in soil microecological restoration mediated by Cyperus malaccensis and Phragmites australis in coastal wetland soils at different remediation durations. We analyzed soil chemistry, enzyme activity, and microbial communities at three depths (0–20 cm, 20–40 cm, 40–60 cm) in C. malaccensis , P. australis , and unvegetated tidal flat plots at 8 and 16 years after remediation. C. malaccensis enriched a predominantly bacterial microbial community, with nitrogen content in its topsoil increasing with remediation duration. P. australis tended to enrich fungal communities, focusing on long-term improvement of deeper soil layers. Microbial community assembly was primarily controlled by stochastic processes (βNTI < 2), but P. australis plots maintained higher functional diversity. Co-occurrence network analysis indicated C. malaccensis promoted modular structure of the bacterial community and enhanced stability, while P. australis optimized fungal functional cooperation and improved deep soil nutrient cycling efficiency. Different vegetation types drive soil microecological restoration via distinct plant-soil feedback pathways: C. malaccensis improves topsoil fertility through bacteria-dominated synergies for short-term nutrient enhancement, whereas P. australis strengthens deep soil function and long-term stability via deep-root-mediated fungal regulation. Thus, introducing suitable native vegetation in coastal wetland restoration regulates plant–microbe interactions, accelerating and optimizing soil ecological restoration more effectively than natural tidal flat succession.
Yuan et al. (Sat,) studied this question.