Spatial characteristics of the dominant fungi and their driving factors in forest soils in the Qinling Mountains, China

Soil fungi are essential in nutrient cycles in forest ecosystems, however, the spatial patterns and the driving factors on its community may be different among different forest ecosystems. Here, the spatial patterns of the dominant forest soil fungi at phyla and class levels and their driving factors were investigated in the Huoditang (~22 km²) in the Qinling Mountains, China. The results indicated that Ascomycota and Basidiomycota were the dominant phyla, and Agaricomycetes, Sordariomycetes and Archaeorhizomycetes were the dominant classes in this region. The patches occupied by the dominant fungi were divided into six categories. Rozellomycota (5.58 km²) occupied the greatest area at the highest patch category, and Ascomycota (1.43 km²) was the second. However, the number of patches at the highest category occupied by Ascomycota was the most. Among the dominant fungal classes at the highest patch category, the habitat of Sordariomycetes was the greatest (4.59 km²) and Pezizomycetes occupied the greatest area (17.84 km²) at the lowest patch category. Overall, the dominant fungi showed “peak”, “bimodal”, and “multimodal” distributions in kriging interpolation maps. Variance partitioning analysis indicated that soil characteristics and topographic factors explained (p < 0.05) 51.46% and 71.26% of the total variation in the spatial pattern of the dominant fungal phylum and class, respectively, the explanation of soil properties (39.19% and 61.04%) was much higher than that of topographical factors (12.27% and 10.22%). The redundancy analysis indicated that the combination of soil pH, electrical conductivity, available phosphorus, and soil organic matter significantly influenced the spatial characteristics of the dominant fungi, which was different from single factor on fungi community in other ecosystems. The findings can improve our understanding of the spatial characteristics of the dominant soil fungi in the subtropical forest ecosystems.