Effects of ecological restoration on soil microbial carbon fixation in the coastal wetlands of the Yellow River Delta

Coastal wetlands are important blue carbon ecosystems, and microbial carbon fixation is a key process contributing to soil carbon sequestration. Ecological restoration has been widely implemented to recover the structure and functioning of degraded coastal wetlands, yet its effects on microbial carbon fixation remain insufficiently understood. In this study, soils were collected from freshwater-restored wetlands (FRZ), Suaeda salsa-restored wetlands (SRZ), and unrestored natural Suaeda salsa wetlands (NSZ) in the Yellow River Delta to evaluate microbial carbon fixation potential, key functional genes, and metabolic pathways. The data mainly include soil physicochemical parameters, carbon pool component contents, diversity of carbon-fixing microorganisms, relative abundances of carbon fixation pathways and genes, and diversity of carbon-fixing microbial communities across different restoration zones. These results elucidate the mechanisms by which ecological restoration regulates microbial carbon fixation processes through changes in soil conditions, and provide a basis for enhancing carbon sequestration capacity and optimizing restoration strategies in coastal wetlands.