Effects of Land Use Changes on Soil Fungal Community Structure and Function in the Riparian Wetland Along the Downstream of the Songhua River

The aim of this study was to provide a reference for wetland resource management and ecological restoration by analyzing the influence of land use changes on the soil fungal community and its function and to identify the potential natural restoration ability of degraded riverside wetlands in the Songhua River. In July 2018, soil fungi in a natural wetland, paddy field, sand mining slash, and restoration wetland along the downstream of the Songhua River were amplified by PCR. PCR products were sequenced using the Illumina MiSeq PE300 high-throughput sequencing platform. The differences in the soil fungal community composition and function and its influencing factors were analyzed. The results showed that the α-diversity indexes of soil fungi were significantly reduced by sand mining or cultivation in the natural wetland (P 1%). Ectomycorrhizal was the main functional fungus in the natural wetland and restoration wetland with the supplementation of bryophyte parasites and lichen parasites. Litter saprotrophs and soil saprotrophs were the main functional groups of fungi in the paddy field and sand mining slash, and the relative abundances of animal pathogens and plant pathogens increased significantly in the paddy field. The diversity of the soil fungal community was significantly influenced by the soil pH, organic carbon, total nitrogen, and total phosphorus contents. Thus, resource development in the natural riparian wetlands reduced the ecosystem stability and increased the potential ecological risks.