Responses of Arbuscular Mycorrhizal Fungal Communities to Invasion of Spartina alterniflora in Coastal Wetlands at Spatial and Temporal Scales

As an exotic plant, Spartina alterniflora seriously threatens the ecosystem function of coastal areas in my country. Most plants can form symbiotic mycorrhizal associations with arbuscular mycorrhizal fungi (AMF), greatly influencing the outcome of interplant competition. In this study, with the focus on tufted mycorrhizal fungi, utilising 16S rRNA gene high-throughput sequencing technology, short-term temporal and spatial series analyzes were conducted on the impacts of Spartina alterniflora on invasion time (year and season) and space on soil nutrients and fungal community composition and structure in coastal wetlands in the Yellow River Delta, China. Results showed that environmental factors had an impact on the AMF community, and soil AP and salinity were the main factors affecting the fungal community structure. The number of operational taxonomic units showed an increasing trend, that is, the diversity of AMF increased with the invasion, and the diversity of Spartina alterniflora rhizosphere AMF community first increased and then decreased, while native plants did not change significantly. AMF overlap between the two accounts for 29.82%, and the difference in core OUT is evident. The distribution patterns of soil AMF of native and invasive plants in wetlands were clearly divided by principal coordinate analysis (PCoA), non-metric multidimensional scaling (NMDS) and canonical correspondence analysis (CCA). Compared with native plants, the rhizosphere AMF community of Spartina alterniflora was more concentrated, and had significant structural differences both in time and space.