Warming changes the composition and diversity of fungal communities in permafrost

Abstract Purpose It is the data support and theoretical basis for the response mechanism of soil fungi to climate warming in permafrost areas in the Greater Xing’an Mountains. Methods We collected permafrost from the Greater Xing’an Mountains for indoor simulation experiments and took the natural permafrost as the control (CK) and the test groups of 0 °C (T1), 2 °C (T2), and 4 °C (T3) were set. Illumina MiSeq high-throughput sequencing technology was used to understand the changes in characteristics of fungal communities, and the correlations were analyzed combined with the soil physicochemical properties. Results Compared with CK, the value of pH and the content of available potassium (AK) in the three warming treatment groups were significantly lower (P < 0.05), and the microbial biomass carbon (MBC) content was significantly higher (P < 0.05). The content of total nitrogen (TN) and available nitrogen (AN) in the T1 and T3 groups was significantly lower than that in the CK group (P < 0.05). A total of 11 phyla, 39 classes, 89 orders, 187 families, 361 genera, and 522 species were obtained through fungal sequencing and divided into 1463 amplicon sequence variants (ASVs). Ascomycota and Dimorphospora were the dominant phylum and genus, respectively, and there were differences in the response of relative abundance of various groups at the phylum and genus levels to warming. Warming significantly decreased the Sobs and ACE indexes of the treatment groups (P < 0.05), and the Shannon and Shannoneven indexes also showed a downward trend. Moreover, warming significantly changed the fungal beta diversity (P < 0.01), while the value of pH and the content of TN, MBC, and AK could significantly affect the community structure (P < 0.05), and the correlation between fungi at different phyla levels and soil physicochemical properties was different. Conclusions These results can provide a reference for further study on the changes in composition and structure of fungal communities and the influence factor in permafrost in the Greater Xing’an Mountains under the background of warming.