Phosphorus amendment alters soil arbuscular mycorrhizal fungal functional guild compositions in a subtropical forest

PurposeNitrogen (N) and phosphorus (P) amendments considerably influence fungal diversity and community composition in various ecosystems. Nevertheless, how N and P additions would change arbuscular mycorrhizal (AM) fungal community and functional guilds in forest soil remains largely unclear.Materials and methodsA 5-year N and P addition experiment was conducted in a subtropical forest of southeastern China. Soil AM fungal communities were detected by the high throughput sequencing of 18S rRNA gene-fragments. We investigated the six-seasonal responses of AM fungal diversity, community assembly pattern and functional guild composition to N and/or P amendments.Results and discussionThe AM fungal Shannon index changed from a positive (3-4 years) to a nonsignificant (4-5 years) effect under P and NP additions as the duration of fertilization increased. P addition, but not N addition, changed the AM fungal community assembly pattern from stochastic- to deterministic-dominant processes. In contrast, P and NP additions significantly influenced AM fungal functional guild components, and the relative abundances of ancestral and edaphophilic guilds increased with increasing years of fertilization. Additionally, the AM fungal guild structure was significantly affected by soil P-related parameters.ConclusionsOur results emphasize the substantial impacts of P amendment on soil AM community assembly pattern and functional guild composition. This study contributes to a better understanding of the temporal dynamics and potential ecological functioning of AM fungi under global environmental changes.