The effects of different revegetation types on soil physical–chemical characteristics and fungal community diversity and composition of soils sampled from five different revegetation types (JM, Juglans mandshurica; QM, Quercus mongolica; conifer-broadleaf forest (CB); LG, Larix gmelinii; PK, Pinus koraiensis) in the Baishilazi Nature Reserve were determined. Soil fungal communities were assessed employing ITS rRNA Illunima Miseq high-throughput sequencing. Responses of the soil fungi community to soil environmental factors were assessed through canonical correspondence analysis (CCA) and Pearson correlation analysis. The coniferous forests (L. gmelinii, P. koraiensis) and CB had reduced soil total carbon (C), total nitrogen (N), and available nitrogen (AN) values compared with the broadleaf forest (J. mandshurica, Q. mongolica). The average fungus diversity according to the Shannon, ACE, Chao1, and Simpson index were increased in the J. mandshurica site. Basidiomycota, Ascomycota, Zygomycota, and Rozellomycota were the dominant fungal taxa in this region. The phylum Basidiomycota was dominant in the Q. mongolica, CB, L. gmelinii, and P. koraiensis sites, while Ascomycota was the dominant phylum in the J. mandshurica site. The clear differentiation of fungal communities and the clustering in the heatmap and in non-metric multidimensional scaling plot showed that broadleaf forests, CB, and coniferous forests harbored different fungal communities. The results of the CCA showed that soil environmental factors, such as soil pH, total C, total N, AN, and available phosphorus (P) greatly influenced the fungal community structure. Based on our results, the different responses of the soil fungal communities to the different revegetation types largely dependent on different forest types and soil physicochemical characteristic in Baishilazi Nature Reserve.

Soil microorganisms play important roles in the dynamic regulation of organic matter in the forest ecosystem and are affected by different revegetation types. To reveal the influence of different revegetation types on soil microorganisms, we examined soil properties, soil microbial activity and diversity in Baishilazi Nature Reserve, including two planted coniferous forests (LG: Larix gmelinii, PK: Pinus koraiensis), two natural secondary broadleaf forests (JM: Juglans mandshurica, QM: Quercus mongolica), and one conifer-broadleaf forest (CB). Biolog-Eco plates were used to study soil microbial functional diversity. We found that the content of soil total C and total N existed higher under the broadleaf forests (JM, QM) than conifer-broadleaf forest (CB) and coniferous forests (LG, PK). Carbon source utilization capacity and soil microbial activity showed significant variations among different revegetation types. Soil microbial activity of natural secondary forests was significantly higher than planted coniferous forests, and JM created the highest soil microbial activity. Heatmap and PCA plot clearly differentiated among the different samples. The broadleaf forests, conifer-broadleaf forest and coniferous forests were well separated from each other, especially along the PC1, and the position of conifer-broadleaf forest was intermediate. The findings of canonical correspondence analysis (CCA) suggested that soil total C and total N were the main factors affecting soil microbial functional diversity. This study investigated how shifts in soil microbial functional diversity affected by different revegetation types were operational indicators of soil quality